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Existing multiterminal voltage source converter based high voltage dc projects are constructed by separate modular multilevel converter (MMC) and dc breaker (DCB) utilizing insulated gate bipolar transistors. However, the MMC requires high-surge thyristors and the DCB should be equipped with very large turn- off solid-state switch against fault. Their independent operations are complex and unreliable by two separate control systems. In this letter, a novel converter-breaker integrated voltage source converter (IVSC) based on high-surge integrated gate commutated thyristor is proposed, and to integrate the converter and breaker operation, the fault self-clearing strategy is developed. IVSC can get rid of thyristors and replace DCB with small turn- off capability load switch. This converter-breaker integration can result in advantages including lower manufacturing cost and volume.

Current low-voltage load switches do not support remote disconnect/connect and real-time monitoring of a disconnect/connect state. Addressing to these issues, this paper presents a low-voltage load switch for a smart remote control system, which uses a one-chip microcontroller board and a DC step motor drive mechanism and provides the feedback on the switch status also. Arrears disconnect and full-pay connect control is implemented via the microcomputer and Hall sensor. The low-power supply and state feedback circuit are designed to reduce the power consumption. And the motor drive mechanism is optimized to improve the performance of motor. Finally, a test environment includes the system control and feedback is created to illustrate the feasibility of the designed low-voltage switch. The test results that the design supports disconnect/connect control and state feedback in various conditions validate the feasibility of this designed system, which has high practical value and is worthy of promotion.

Wearable and implantable technology for respiratory monitoring has created the potential for continuous collection of respiratory parameters for healthcare and other applications. However, battery life, form factor, and user burden impose practical constraints that affect user acceptance and therefore clinical utility. This work introduces a wireless self-powered sensing system for airway monitoring that uses an array of piezoelectric cantilevers that functions as both the respiratory flow sensor and the energy harvester that powers the system. The cantilevers are excited by airflow in the airway, and the harvested energy from the cantilevers is stored in a capacitor. Once a threshold energy is available in the capacitor, a load switch closes and enables a low frequency oscillator that functions as a data-less transmitter. The signal coming from the sensing system is received by an external software-defined radio (SDR), and the rate at which this signal is received is mapped to the respiratory conditions in the airway. A benchtop testing system that incorporates a lung simulator, a data acquisition system, and a hot wire anemometer was created to validate the sensor. Results show that the signal reception rate is affected by the breathing rate and volume, demonstrating the potential for a self-powered, miniaturized, passive implantable device for continuous respiratory health monitoring.

This work describes an optimum utilization of hybrid photovoltaic (PV)—wind energy for residential buildings on its occurrence with a newly proposed autonomous fuzzy controller (AuFuCo). In this regard, a virtual model of a vertical axis wind turbine (VAWT) and PV system (each rated at 2 kW) are constructed in a MATLAB Simulink environment. An autonomous fuzzy inference system is applied to model primary units of the controller such as load forecasting (LF), grid power selection (GPS) switch, renewable energy management system (REMS), and fuzzy load switch (FLS). The residential load consumption pattern (4 kW of connected load) is allowed to consume energy from the grid and hybrid resources located at the demand side and classified as base, priority, short-term, and schedulable loads. The simulation results identify that the proposed controller manages the demand side management (DSM) techniques for peak load shifting and valley filling effectively with renewable sources. Also, energy costs and savings for the home environment are evaluated using the proposed controller. Further, the energy conservation technique is studied by increasing renewable conversion efficiency (18% to 23% for PV and 35% to 45% for the VAWT model), which reduces the spending of 0.5% in energy cost and a 1.25% reduction in grid demand for 24-time units/day of the simulation study. Additionally, the proposed controller is adapted for computing energy cost (considering the same load pattern) for future demand, and it is exposed that the PV-wind energy cost reduced to 6.9% but 30.6% increase of coal energy cost due to its rise in the Indian energy market by 2030.

Due to the high global warming potential (GWP) of SF 6 , the use of new gases in electrical equipment has drawn increasing attention. Here, the application of environmental-friendly gas dodecafluoro-2-methylpentan-3-one (C 6 F 12 O) and CO 2 mixture in 10 kV medium-voltage switchgear is studied. First, the basic physical and chemical properties of C 6 F 12 O were discussed, and the toxicity and safety of its application in equipment was analysed. Then, the breakdown voltage was measured in the laboratory. The power-frequency breakdown test was carried out with the mixing ratio of 2, 4 and 6% at 0.1~0.2 MPa, and the influence of utilisation coefficient of electric field on the breakdown performance was analysed. Finally, the appropriate mixing ratio was determined and tested in the load switch cabinet and the circuit breaker switch cabinet, including the power frequency withstand voltage test and the lightning impulse test. The test results show that 4% C 6 F 12 O and CO 2 meet the standard value tested at a pressure of >0.14 MPa, which has the potential to be used as an insulating gas in a 10 kV switchgear.

Energy efficient sensing is one of the main objectives in the design of networked embedded monitoring systems. However, existing approaches such as duty cycling and ambient energy harvesting face challenges in railway bridge health monitoring applications due to the unpredictability of train passages and insufficient ambient energy around bridges. This paper presents eco-friendly vibration (ECO VIBE), an on-demand sensing system that automatically turns on itself when a train passes on the bridge and adaptively powers itself off after finishing all tasks. After that, it goes into an inactive state with near-zero power dissipation. ECO VIBE achieves these by: first, a novel, fully passive event detection circuit to continuously detect passing trains without consuming any energy. Second, combining train-induced vibration energy harvesting with a transistor-based load switch, a tiny amount of energy is sufficient to keep ECO VIBE active for a long time. Third, a passive adaptive off control circuit is introduced to quickly switch off ECO VIBE. Also this circuit does not consume any energy during inactivity periods. We present the prototype implementation of the proposed system using commercially available components and evaluate its performance in real-world scenarios. Our results show that ECO VIBE is effective in railway bridge health monitoring applications.

The soft open point (SOP) using the back to back power converter can flexibly, fast and accurately regulate the power flow among the adjacent feeders by implementing the multi-targets control including nodes voltages and network losses and also has the capability to isolate the fault and recover the power supply. However, the range of power restoration is strictly limited by the SOP capacity. This paper proposes a hybrid soft open point system with a partial scale back to back converter and a load switch parallel connected. The power flow and voltage distribution could be regulated by the back to back converter as usual. And the load switch could realize power recovery for all the customer interruption under the fault condition. Moreover, the back to back converter can flexibly regulate the power flow through the load switch and help realize the zero current turning off of the load switch, which can effectively extend the working life of the load switch and reduce the equipment cost. Furthermore, the performance of the proposed hybrid SOP is verified by the simulation results.

Interface transformer used in asynchronous networking was a kind of special transformer which's different from normal power transformer. During no-load switch-in, the magnitude of inrush current will be high, and the waveform distortion also be severity. Maybe the protections will be activated, even worse may lead the lockdown of the DC system. In this paper, field-circuit coupled finite element method was used for the study of transient characteristic of no-load switch-in, remanence simulation methods were presented. Quantitative analysis of the effect of closing making angle and core remanence on inrush current peak value, meanwhile, the distribution of magnetic field inside the tank during the transient process. The result indicated that the closing making angle and core remanence have obvious effect on inrush current peak value. The research results of this paper can be used to guide the formulation of no-load switch-in strategy of interface transformer, which was of great significance to ensure the smooth operation of HVDC Flexible system.

SF 6 gas is a good electric medium for its excellent arc extinguishing properties. However, SF 6 is a strong greenhouse effect gas with a global warming potential (GWP) of 23,900 times that of CO 2 . It is urgent to find a SF 6 alternative gas for electrical industry. Nowadays, some kinds of gases are filtered as candidates, and C 4 F 7 N is considered the most likely gas to replace SF 6 in the future. Although C 4 F 7 N has a good arc extinguishing property in general, C 4 F 7 N cannot be used alone in power equipment and it has to be mixed with some buffer gases like CO 2 with a determined mixing ratio. Because the arc extinguishing mechanism of C 4 F 7 N/CO 2 in load switch is not clear, in this paper the arc extinguishing performance of gas mixture is studied by numerical simulation. Physical parameters of C 4 F 7 N mixture are the data basis for simulation calculations and the accuracy of them has a great impact on the simulation. Because the physical parameters are mostly affected by pressure and temperature, they are all calculated by gas pressure and temperature. The magneto-hydrodynamic (MHD) model is an effective way to describe the process of arc extinguishing. A two-dimensional axisymmetric arc MHD model is established by adding specific source terms based on the flow field control equations. The influence of the ratio of C 4 F 7 N/CO 2 mixture is investigated to explore the C4F7N mixture arc extinguishing performance in load switch. According to MHD analysis, the important parameters such as the rising rate of recovery voltage can be got which is considered as a judging criterion whether the current breaking succeed or not. It can provide sufficient theoretical ways to improve arc extinguishing performance of load switch.

SF 6 gas is widely used in power equipment for its excellent arc extinguishing and insulation properties. However, SF 6 is a strong greenhouse effect gas with a global warming potential (GWP) of 23,500 times that of CO 2 . Therefore, the Kyoto Protocol signed in 1997 has included SF 6 in one of the six greenhouse gases which are restricted for use. Nowadays, finding an environmentally friendly alternative gas for SF 6 is a hot issue in the world. The research on SF 6 environmental alternative gas has made great progress these years. C5F 10 O is considered the most likely gas to replace SF 6 in the near future. Although C 5 F 10 Ohas a good arc extinguishing property in general, the arc extinguishing mechanism of it in the load switch is not clear. Because arc extinguishing is a complex physical and chemical process involving the interaction of gas flow fields, electromagnetic fields, and ablation the nozzle materials. In this paper, by combining the computational fluid dynamics (CFD) analysis and the Mayr arc model the interruption processes for a load switch filled with 5%C 4 F 7 N/CO 2 and 5%C 5 F 10 O/CO 2 at 0.135 MPa, as well as pure SF6 and CO 2 at 0.135 MPa, are investigated. The time constant θ and arc cooling coefficient $Q$ at the current zero point is calculated based on the Mayr equation. In the end, the critical values of the rising rate of the recovery voltage (RRRV) are obtained. These parameters are the most important issues to determine whether breaking success or not. Through the analysis of the post arc medium recovery, the arc extinguishing performance of different gas medium can be theoretically and quantitatively evaluated. It can provide a sufficient theoretical basis to enhance the arc extinguishing ability of the load switch through the CFD analysis.

International audience; In this paper, an innovative millimeter-wave (mm-wave) through-load switch for in-situ reflectometers and on-wafer calibration is proposed. This two-port device can switch between two states: (i) a through connection or (ii) a 50 Ω load for both of its ports. The through-load switch is composed of a 3-dB directional coupler and two nMOS transistors controlled through a biasing voltage applied to their gate. Measurement results of a 120-GHz 3-dB directional coupler are provided up to 145 GHz together with EM simulations and circuit-level simulations up to 220 GHz of the through-load switch. A wide bandwidth is obtained, from 73 GHz to 179 GHz, with limited insertion loss of 2 dB.

So far, we have been discussing pre-timed signals which is a non-traffic responsive control system, while in many cases traffic responsive control is desirable. That is, the right-of-way and duration of GREEN time is dynamically allocated depending on traffic demand. A signal system of this kind is called actuated signal system. In preparation for the topic, this chapter introduces hardware equipment and devices that are used for intersection signalization. The difference of pre-timed and actuated control will be contrasted, and the architecture of controller cabinet will be highlighted. This is followed by an in-depth discussion on various components in the cabinet—their functionalities and working principles. Particular attention is directed to the mechanism of how to ensure safety of signalized intersection.

The existing electric energy meter load switches have issues such as a low electrical life, poor resistance to short-circuit currents, high contact point resistivity and severe heating. Research has thus been conducted on the optimization of the electric energy meter built-in load switch mechanism to establish a double response surface model for the electromagnetic attractive force and reed reaction force. The model introduces a niche fitness sorting strategy and a Gaussian mutation mechanism that are based on the standard particle swarm algorithm and form an improved multi-objective particle swarm optimization algorithm in which the static attractive force is regarded as the optimization objective. The multi-objective optimization of the structural parameters of the electromagnetic system and the reed system was carried out, and the optimization results were applied in the devices’ design and implementation. The new structure improves the electromagnetic suction and reed force at the suction position. And the results from simulation show that the proposed method exceeds that of the back propagation neural network method in achieving the optimization goal and the new structure can effectively improve the performance of meter built-in load switch by avoiding the recoil phenomenon.

Electric water heaters (EWHs) remain one of the main contributors to energy consumption in countries where they are used. EWH models serve as a step towards achieving optimised control, and can also be used to inform users of expected savings due to changes, if the model is energy-based. Various models have been proposed, but none of them include more than half of the six key features that the model presented in this paper supports: horizontal orientation; schedule control; low computational complexity; validation of the model; multinodal stratification; and multinodal standing losses. The presented model is validated against six datasets: four comprising 900 hours with multiple water usage events; and two with only standing losses. The results show that the model estimates energy consumption over ten days including usage with an error of less than 2% and 5% for schedule control and thermostat control respectively. The simulation model is simple enough to execute ten days of simulation in less than 100 milliseconds on a standard desktop machine, 150 times faster than a prominent model from literature, making it also suitable for large scale simulations or for use on mobile devices.

This paper proposes the use of a novel algorithm for smart-direct load control (S-DLC) and load shedding to minimize power outages in sudden grid load changes and reduce the peak-to-average ratio. The algorithm utilizes forecasting, shedding, and S-DLC. It also uses the Internet of Things and stream analytics to provide real-time load control, and generates a daily schedule for customers’ equipped with intelligent electronic devices based on their demands, thermal comfort, and the forecasted load model. The demand response techniques are utilized for real-time load control and optimization. To test the algorithm, a simulation system was developed, which takes into account 100 customers owning randomly selected appliances. The results indicated that load shedding using autoregressive integrated moving average time-series prediction model, and applying S-DLC and Internet of Things can significantly reduce customers’ power outage.

Demand response is expected to help maintain the supply and demand balance of the power system. In Japan, various demonstration projects have been carried out to evaluate the effect of demand reduction. Commercial air conditioners are a promising responsive load for demand response because they account for a large proportion of power consumption in the power system. In this study, we estimate the potential for system-wide demand reduction through controlling commercial air conditioners. Power consumption of air conditioner changes by the outdoor air temperature. The air-conditioning power consumption model is established based on efficiency characteristics of air conditioner depending on outdoor temperature and load factor. A thermal load simulation is performed assuming demand response implementation in the model buildings and the potential demand reduction is estimated considering user comfort. Our results show that demand reduction through air conditioner control is a viable strategy.

The application of an integrated protection and control system for a 10kV smart electricity distribution grid in China Southern Power Grid is presented in this paper. The system can provide current differential protection for 10kV feeders if CBs are installed on the feeders, or fault location function if load switches are installed on the feeders. It also provides a wide area control function for automatic fault isolation and auto-switching function for restoration of power supplies to the healthy part of a feeder after a power system fault is cleared. Both the current differential protection function and the wide area control function can use either Package Transmission communication Network (PTN) of fibre network or 4G LTE (Long Term Evolution) of wireless communication network. In addition, if the topology of electricity distribution network changes, the system can detect the change and automatically send new configuration settings to the affected current differential protection without manually changing the settings. Factory tests have been carried to prove the effectiveness of the system. Compared to the traditional protection and control system for 10kV distribution networks, the system developed can locate and isolate a fault within 900ms (assuming load switch operating time is 700ms), whereas the traditional system has no fault location function, it may take minutes even hours to manually locate a fault, and then restore power supplies. The integrated protection and control system has been installed and commissioned on site recently, and hopefully it will improve the reliability of power supply significantly.

In this paper, a detailed home energy management system structure is developed to determine the optimal dayahead appliance scheduling of a smart household under hourly pricing and peak power-limiting (hard and soft power limitation)-based demand response strategies. All types of controllable assets have been explicitly modeled, including thermostatically controllable (air conditioners and water heaters) and nonthermostatically controllable (washing machines and dishwashers) appliances, together with electric vehicles (EVs). Furthermore, an energy storage system (ESS) and distributed generation at the end-user premises are taken into account. Bidirectional energy flow is also considered through advanced options for EV and ESS operation. Finally, a realistic test-case is presented with a sufficiently reduced time granularity being thoroughly discussed to investigate the effectiveness of the model. Stringent simulation results are provided using data gathered from real appliances and real measurements.

The selection and operation of drop-out fuse of distribution transformer of the traditional pole type have the disadvantages of large protection characteristics, poor overload protection ability, high failure rate of large current, and easy intrusion and winding of foreign objects. This paper introduces the principle of built-in high voltage protection distribution transformer, and puts forward a new type of distribution transformer protection configuration with the combination of magnetic holding load switch and the backup current limiting fuse. By comparing with the selection methods and functional characteristics of falling fuse protection curves at home and abroad, it establishs the selection and coordination model of the time current characteristic protection curve of the magnetic holding load switch and the reserve current limiting fuse. The development and test of built-in high voltage protection distribution transformer are completed. The operation effect and technical economy of the built-in high voltage protection distribution transformer are analyzed, and it's popularization and application in the future is prospected.

A power switch solution for a space environment using commercial off the shelf (COTS) devices is presented. The application was for a high load switch required to turn-on within 1 us that could support greater than 600 volts and current requirement of 15 amperes. The susceptibility of devices to single-event gate rupture (SEGR) and single-event burnout (SEB) was seen to correlate to the off resistance (RDSoff) and gate thickness of the devices.

Although the locational marginal price may change dramatically within a single day in competitive wholesale electricity markets, most end users are charged monthly electricity bills over flat rates. Without financial incentives, the customers are lacking of motivation to respond to the price signals, which may result in inefficient energy consumption. In Texas, Senate Bill 1125 encourages qualified residential and commercial customer classes to participate in demand response (DR) programs. This paper proposes an idea to aggregate a number of residential customers to participate in residential DR program by employing smart appliances and a home area network to shift the coincidental peak load to off-peak hours to reap financial benefits. The operation strategies for the most representative residential load types are discussed. To further reduce electricity purchase and cut electricity bills, a solar farm with energy storage system is proposed, and the control algorithm is designed accordingly. The operation strategies are simulated for a whole year, and the annual costs are calculated and compared in this paper. The results show that, by doing load control and utilizing renewable resources, the total operation cost can be reduced significantly.

Demand response can be used for providing regulation services in the electricity markets. The retailers can bid in a day-ahead market and respond to real-time regulation signal by load control. This paper proposes a new stochastic ranking method to provide regulation services via demand response. A pool of thermostatically controllable appliances (TCAs) such as air conditioners and water heaters are adjusted using direct load control method. The selection of appliances is based on a probabilistic ranking technique utilizing attributes such as temperature variation and statuses of TCAs. These attributes are stochastically forecasted for the next time step using day-ahead information. System performance is analyzed with a sample regulation signal. Network capability to provide regulation services under various seasons is analyzed. The effect of network size on the regulation services is also investigated.

This paper proposes a novel optimization based home load control (HLC) to manage the operation periods of responsive electrical appliances, determine several recommended operation periods for nonresponsive appliances, and schedule the charge/discharge cycling of plug-in hybrid electric vehicle (PHEV) considering various customer preferences. The customer preferences are in the format of payment cost, interruption cost, and different operational constraints. The projected algorithm is online, in which household appliances are initially scheduled based on the payment cost, and when the home load is interrupted, the scheduling will be updated to minimize customer interruption cost. Due to vehicle to home capability of PHEV, the home outage can be managed through solving the proposed optimization problem. Several realistic case studies are carried out to examine the performance of the suggested method. In addition, the impacts of common electricity tariffs on the HLC results are investigated. The results reveal that employing the proposed HLC program benefits not only the customers by reducing their payment and interruption costs, but also utility companies by decreasing the peak load of the aggregate load demand.

This paper presents a method for smart house electricity load control. The method, combined with TOU price and Real-time pricing, arranges various appliances and meets daily household electricity demand at the same time, so that to reduce the daily electricity consumption and realize Demand Response. First, this paper attempts to summarize problem witch need to be solved for realizing load control in a smart house. Second, the smart house load control problem was described as high-dimensional complex functions unconstrained optimization model and solved with Particle Swarm Optimization. Finally, design experiments used the method for a smart house. Experimental results show that the method can arrange various appliances and reduce electricity consumption.

The main objective of this work is to design and construct a PoE switch based system: to control electric appliances such as light, fan, heater, washing machine, motor, TV, etc. and simultaneously data communication facility. Especially PoE switch can manage power and data separately by a splitter which motivated the need to research into it not only for industrial application but also for domestic use or home use. Power is use for controlling devices and data is for communication purpose. This system will play an important role for the elderly and physically disabled people to control their home appliances in intuitive and flexible way through Wi-Fi and internet. This system is password protected so only authorized person can control any sensitive electrical appliances. Most commercially available home automation systems are used only for control purpose. But by our proposed PoE based system we can control electrical appliances as well as data communication by the same switch port.

dc fault isolation is the key problem in the flexible dc system. At present the dc circuit breaker which could operate fast enough with a large fault current is still unavailable. Based on the dc fault transient characteristics in the dc system based on the modular multilevel converter (MMC), a feasible isolating method was developed by improving the topology of the MMC, which limits the dc-side cable current to a lower level and then interrupts the fault circuit by a dc load switch. Comparisons between different isolating methods show the superiorities of the proposed method. Simulation tests were carried out using MATLAB/Simulink and the feasibility of the proposed isolating method was demonstrated.

Residential electric load shaping is often implemented as infrequent, utility-initiated, short-duration deferral of peak demand through direct load control. In contrast, investigated herein is the potential for frequent, transactive, intraday, consumer-configurable load shaping for storage-capable thermostatically controlled electric loads (TCLs) including refrigerators, freezers, and hot water heaters. Unique to this study are 28 months of 15-minute-interval observations of usage in 101 homes in the Pacific Northwest United States that specify start, duration, and usage patterns of approximately 25 submetered loads per home. The magnitudes of the load shift from voluntarily-participating TCL appliances are aggregated to form hourly upper and lower load-shaping limits for the coordination of electrical generation, transmission, distribution, storage, and demand. Empirical data are statistically analyzed to define metrics that help quantify load-shaping opportunities.

This paper focuses on an experimental investigation of the arc plasma behavior in current breaking process of a certain type of 12kV ring network cabinet’s SF6 load switch. From the frames obtained by high-speed photography, the characteristic of the arc movement was revealed. According to analysis, the structure of load switch was optimized and its breaking capacity about transfer current was improved. This study may provide a reference for design and optimization of load switches.

This paper proposes a distributed direct load control scheme for large-scale residential demand response (DR) built on a two-layer communication-based control architecture. The lower-layer network is within each building, where the energy management controller (EMC) uses wireless links to schedule operation of appliances upon request according to a local power consumption target. The upper-layer network links a number of EMCs in a region whose aggregated demand is served by a load aggregator. The load aggregator wants the actual aggregated demand over this region to match a desired aggregated demand profile. Our approach utilizes the average consensus algorithm to distribute portions of the desired aggregated demand to each EMC in a decentralized fashion. The allocated portion corresponds to each building's aforementioned local power consumption target which its EMC then uses to schedule the in-building appliances. The result will be an aggregated demand over this region that more closely reaches the desired demand. Numerical results show that our scheme can alleviate the mismatch between the actual aggregated demand and the desired aggregated demand profile.

FinFETs are emerging as a replacement for traditional MOSFETs due to their better performance in the subthreshold region. The lowering of leakage current and improved on-off current ratio gives these quasi-planar structures an upper hand over MOSFETs. Being compatible with CMOS technology with a few additional fabrication steps further enhances the chances of FinFETs becoming state of the art semiconductor technology. Power consumption in transistors occur mainly due to switching action and leakage. Technology scaling results in tremendous increase in leakage power component. Design of devices with reduced leakage and minimum delay at the same time requires scaling of operating voltage as well as gate sizing. Presence of multiple gates opens the scope for various modes of operation of the FinFET based circuits. Motors are the most common form of actuators in any mechatronic system. For efficient power management load switches are incorporated in the drive circuits. The load switch connects and disconnects a specific load from the supply in accordance with the signal from the control circuitry. Due to the advantages of FinFETs they can be used to replace the existing MOSFET load switches in the drive circuits. The paper discusses usage of FinFETs in IoT controlled stepper motor drive circuits used in robotics linked to the Internet of Things (IoT).

This paper presents the concept of controlling distributed electric loads with thermal energy storage as a passive electric energy storage system (PEESS). Examples of such loads include different types of thermostatically controlled appliances (TCAs) such as hot water heaters, air conditioners, and refrigerators. Each TCA can be viewed as a thermal cell that stores electricity as thermal energy. A centralized control mechanism can be used to control the timing of each thermal cell to consume electric energy so that the aggregated electricity consumption of the thermal cells will vary against a baseline consumption. Thus, when the aggregated consumption is higher than the baseline, the PEESS is charging; otherwise, the PEESS is discharging. The overall performance of a PEESS will be equivalent to that of a battery energy storage device. This paper presents the configuration and formulates the control of a PEESS. The modeling results demonstrate the feasibility of implementing the PEESS.

This paper summarizes the results from a PG&E pilot designed to assess the ability to use air conditioner direct load control to provide ancillary services. The study included nearly 2000 residential households with control devices that were instructed to cause an immediate and complete shutdown of the air conditioner compressor 71 times over a two and half month period. It summarizes the start and total ramp time of AC load response, the magnitude of the response, the effect of the curtailments on customer comfort and satisfaction, and the approach to providing near real time visibility of the air conditioner electricity demand [1].

In order to support the growing interest in demand response (DR) modeling and analysis, there is a need for physical-based residential load models. The objective of this paper is to present the development of such load models at the appliance level. These include conventional controllable loads, i.e., space cooling/space heating, water heater, clothes dryer and electric vehicle. Validation of the appliance-level load models is carried out by comparing the models' output with the real electricity consumption data for the associated appliances. The appliance-level load models are aggregated to generate load profiles for a distribution circuit, which are validated against the load profiles of an actual distribution circuit. The DR-sensitive load models can be used to study changes in electricity consumption both at the household and the distribution circuit levels, given a set of customer behaviors and/or signals from a utility.

Optimization of time-variable operation to maximize revenue through selling and purchasing electricity to/from the grid is presented for a thermal energy storage system. Time-variable electricity prices and electricity buy-back from the grid to re-charge the energy storage is considered by adding electric heaters to the CSPonD concept [Slocum et al., [15] ]. System-level models are developed and optimization of the design and operation is performed. Three case studies are considered: i) time-variable operation without electrical heating under time-invariant electricity price; ii) operation under time-variant electricity price without electric heaters; iii) operation under time-variant electricity price allowing charging of the pond using the grid electricity. These demonstrate the effect of time-invariant versus time-of-use feed-in-tariff. Two hourly price profiles are considered, representing a moderately and highly fluctuating price profile respectively. Uncertainty of the cost function is indirectly addressed: the approach optimizes for the expected value of profit. The results show significant increase in the revenue when adding electric heaters. Under the moderately fluctuating electricity price, the use of heaters increases the revenue significantly, compared to the same case with no electric heaters considered. In the case of highly fluctuating electricity price, the use of heaters more than doubles the revenue.

In this paper, a switched load harmonic rejection mixer (HRM) structure with one single mixer core and a pair of switched load resistors is proposed. Different from the traditional three-phase HRM which is widely used in DTV tuners, this HRM performs the harmonic rejection function by vector multiplication rather than superposition. Sharing most of its parts with an ordinary Gilbert mixer, the proposed HRM shows greater simplicity in structure. The single mixer-core structure is also more power efficient than a traditional three-phase HRM. In order to verify the effectiveness of this approach, a proof-of-concept prototype is designed and fabricated in 0.18- μm RFCMOS technology. Measurements indicate that 38 dB for 3rd and 34.5 dB for 5th harmonic rejection ratio can be achieved. The HRM including a buffer stage consumes a low bias current of 3 mA under 1.8 V supply voltage and has equivalent performance such as CG, NF, and IIP3 to an ordinary Gilbert mixer. With the load switch inactivated, this HRM can be easily transformed into an ordinary Gilbert mixer, which increases its flexibility for different applications.

For a successful implementation of demand response in the residential sector, access to real electricity consumption data and load profiles of major household appliances is crucial. With the advancement of the communication technologies and smart load monitoring devices, access to this information become simpler. This paper investigates characteristic of different communication technologies and their suitability for use in demand response implementation in the residential sector. A smart monitoring and controlling system is integrated into a household's electric appliances to study their daily energy consumption profiles and identify their potential demand response capacity. This paper intends to draw interest on the benefits from using the smart monitoring and controlling system, for instance, it provides real-time energy consumption feedbacks, standby power consumption information and remote load control flexibility. Using these information, the total demand response opportunity and standby energy loss are calculated for selected major appliances.

Direct Load Control in several countries still mean the remote control of electric storage water heaters by Ripple Control (RC) or by Long-Wave Radio Control (LWRC) technology. However this control could be extended to other appliances like freezers, air-conditioners or electric vehicles. Basically, the paper investigates the control following capability of such appliances as well as the impact of the load control on the consumer comfort. A sensitivity analysis of the proposed control model is also included regarding some model parameters and constraints.

A new protection scheme for boundary load switch, implemented by using only transient zero-mode current, is proposed in the paper. For neutral indirectly grounded system, the traditional boundary load switch, which is based on power frequency components, is difficult to determine the direction of single-phase-to-earth fault. In this paper, the transient zero-mode current has been analyzed for single-phase-to-earth fault in neutral indirectly grounded system. It concludes that there is significant difference in magnitude of transient currents between the load side fault and source side fault. Load side fault and source side fault can be distinguished by comparing the magnitude of measured transient zero-mode current with the setting threshold. The simulation tests associated with the typical distribution system in EMTP-ATP validate the protection scheme and algorithm for boundary load switch can work properly.

Demand-side frequency control can complement traditional generator controls to maintain the stability of large electric systems in the face of rising uncertainty and variability associated with renewable energy resources. This paper presents a hierarchical frequency-based load control strategy that uses a supervisor to flexibly adjust control gains that a population of end-use loads respond to in a decentralized manner to help meet the NERC BAL-003-1 frequency response standard at both the area level and interconnection level. The load model is calibrated and used to model populations of frequency-responsive water heaters in a PowerWorld simulation of the U.S. Western Interconnection (WECC). The proposed design is implemented and demonstrated on physical water heaters in a laboratory setting. A significant fraction of the required frequency response in the WECC could be supplied by electric water heaters alone at penetration levels of less than 15%, while contributing to NERC requirements at the interconnection and area levels.

In this work, a smart Air Conditioner scheme is proposed and its adaptation to a Smart Home system is presented. Firstly, working principles of conventional Air Conditioner and the proposed smart Air Conditioner are explained and compared. Then, Petri net model of the smart Air Conditioner is developed in order to enable a good general view of the operation of the smart-Air Conditioner and its adaptation to Smart Home. Moreover, for monitoring and controlling the smart Air Conditioner, a program is prepared by using Keysight VEE 9.3 software. Experimental results demonstrate that the proposed scheme provides a significant savings in electricity bills as well as improving user comfort.

External load switch equipped in electricity meter play an important role in the normal operation of the terminal circuit and equipment. Therefore, it has important practical significance to analyze and improve the common failure modes of external load switch equipped in electricity meter. This paper introduces several common failure modes of external load switch equipped in electricity meter, analyzes the failure modes and takes the corresponding improvement measures, which can effectively improve the reliability of the use of external load switch equipped in electricity meter.

Various smart grid pilots are being initiated worldwide to explore the flexibility in electricity demand of households. The potential flexibility of appliances can be unlocked using either manual or (semi-)automated demand response. In the Dutch smart grid pilot Your Energy Moment the effect of demand response is studied. The participating households are equipped with a smart washing machine or smart tumble dryer. These appliances can be used to manually respond to the dynamic tariff applied in the pilot, or cycles can be programmed to automatically respond to price fluctuations. Based on the pilot results, the total load shift of the washing machine and tumble dryer is quantified. Subsequently, the effect of the program function is studied, focusing on the use of this function and on the flexible hours provided for the schedule horizon. The results show that the load of the smart appliances is shifted in time. This load shift is a consequence of both manual and semi-automated load shift. The latter, semi-automated load shift related to the use of the program function, is however limited. Both the measured manual and semi-automated load shift did not change over time, indicating a structural change in behavior.

This paper puts forward a distributed automation scheme with grounding protection for 10kV aerial wire, which is based on the outgoing line and feeder circuit breaker in substation, the intelligent column circuit breaker and the intelligent load switch. Though the outgoing line and feeder circuit breaker in substation, the intelligent column circuit breaker and the load switch cooperating with each other, Which could isolate and exclude the aerial wire transient fault automatically, and isolate the permanent fault immediately. Practical application results show that the application of the scheme have reduced the hours of power failure, reduced maintenance time and improved the stability of the system.

Fin FETs are emerging as a replacement for traditional MOSFETs due to their better performance in the subthreshold region. The lowering of leakage current and improved on-off current ratio gives these quasi-planar structures an upper handover MOSFETs. Being compatible with CMOS technology with a few additional fabrication steps further enhances the chances of Fin FETs becoming state of the art semiconductor technology. Power consumption in transistors occur mainly due to switching action and leakage. Technology scaling results in tremendous increase in leakage power component. Design of devices with reduced leakage and minimum delay at the same time requires scaling of operating voltage as well as gate sizing. Presence of multiple gates opens the scope for various modes of operation of the Fin FET based circuits. Motors are the most common form of actuators in any mechatronic system. For efficient power management load switches are incorporated in the drive circuits. The load switch connects and disconnects a specific load from the supply in accordance with the signal from the control circuitry. Due to the advantages of Fin FETs they can be used to replace the existing MOSFET load switches in the drive circuits.

With the development of smart home, the amount of household electricity loads is greatly increasing. How to effectively control these loads has been one of the most important issues in the research of smart home system. Keeping the total electricity loads under limitation would ensure the safety of users' electricity consumption. However, limiting the amount of electricity load or simply cutting the electricity off when it exceeds the limit will bring inconvenience to users. This paper proposes a hierarchical group control method of household facility, which classifies household electricity loads according to their importance and formulates a rule of cutting off when the total load exceeds the limitation. Based on the MATLAB software, calculating and simulating the appliances' working state by original Particle Swarm Optimization (PSO) has verified the correctness and effectiveness of the proposed group method. This method can be applied to current smart home control unit to improve the security and convenience of the system.

Introducing home energy controller HEC programs will make the electricity consumption more efficient and smarter. The HEC improves and increases savings in bills for consumers. It also reduces the peak demand and peak to average ratio (PAR) for the utility grid. In this paper an algorithm is proposed for an intelligent HEC to control and manage power consumption for home appliances with simulating demand response (DR) operations. This algorithm controls the common home appliances to attain the minimum energy consumption rates and consequently it reduces the peak loads. It switches the appliances according to their selected priority, and to keep the total consumed power below certain limits. The program is implemented by MATLAB-R2012b for technical validation and solutions. The correct operation of the tool is proved through an example with practical scenarios for various cases of home appliances.