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Electric vehicles (EV) connected to a charging station in a microgrid system is a potential power source for participation in energy management (EM). However, an autonomous controller scheme is required to schedule the charging and discharging of the EV battery for optimal EM. This paper proposes an intelligent EM controller for a workplace with EV integration. A Multi-Agent System (MAS) based coordinated optimization scheme is developed for EM. The optimal charging and discharging schedule is obtained by forecasting the trip pattern of EV based on regression by discretization methodology. Furthermore, the optimization scheme is designed considering monetary benefits to the workplace and the EV owner. The controller scheme is developed using Java Agent Development framework (JADE). The proposed EM scheme is tested with real-world data and the results are verified. 1 2017 IEEE. ACKNOWLEDGMENT This publication was made possible by NPRP grant # NPRP 8-627-2-260 from the Qatar National Research Fund (a member of Qatar Foundation). The statements made herein are solely the responsibility of the author[s]. Scopus

For controls of proton exchange membrane (PEM) fuel cell (FC) systems, it is desirable to achieve accurate tracking of desired net output power with optimal oxygen excessive ratio (OER). In this paper, a cascaded control framework is proposed for the FC output power tracking problem, which is a sequential combination of a multi-input-multi-output (MIMO) robust nonlinear non-interacting (RNNI) controller and a nonlinear disturbance-decoupling (NDD) control scheme. Two major issues are addressed: one is interaction/coupling between the OER and the net output power, and the other is the parametric model uncertainty caused by fluctuations in stack temperature under various operating conditions. Simulation results show that good tracking performance is obtained with the two performance objectives well decoupled, and furthermore the impact from the parameters uncertainty can be removed via a nonlinear compensator.

This paper proposes a hierarchical Multi-Agent System (MAS) based controller architecture for enhanced resiliency during the controller failure condition. A self-healing scheme is proposed for fault detection and recovery during the controller failure. The proposed scheme combines both sentinel agent approach and autonomous workload distribution technique. Further, an acquisitive optimization strategy is implemented for energy management during the power generation failure. Faster response is achieved by programming the agents with a Peer-to-Peer (P2P) interchangeable sender-receiver communication strategy. The proposed controller architecture has been verified by considering a power system case study.

A comparative analysis of the plug-in fuel cell vehicles (PFCV) is studied regarding different topologies, drive cycles and control strategies. To improve the performance of the PFCV, an optimization strategy is proposed at first by regulating the power distribution between the battery and the PEMFC system. Then, a direct multiple shooting (DMS) algorithm is used to solve this nonlinear programming problem (NLP) over spatial domain. In view of two topologies of the PFCV, the proposed strategy is compared with the charge-depleting charge sustaining (CDCS) strategy based on four drive cycles. Simulation results demonstrate that, for those cycles of frequent braking operations, the proposed strategy is able to reduce the hydrogen consumption as well as the on-off switching frequency of the PEMFC system. However, the CDCS strategy shows better PFCV's total efficiency than the proposed strategy for all drive cycles, and achieves a slight reduction of the hydrogen consumption for the high speed drive cycles with less braking operations.

In automotive testing systems such as chassis dynamometers and engine dynamometers, predictive current control (PCC) can be used to provide fast torque response, and open-end winding topology can be used to reduce torque ripples. In this paper, a novel predictive current control method based on A-B-C frame, without using cost function, for open-end winding induction motor drive is proposed and implemented. The experimental results show that the proposed method reduces the computation time by 61.05% compared with conventional predictive current control method. It also reduces zero-sequence current and provides faster dynamic response.

This paper presents a virtual RLC damper for resonance damping in an LCL-type grid-connected voltage source inverter by capacitor current feedback through a second-order high pass filter. The proposed method can achieve good damping performance and enhance the system stability by inherently compensating phase lag around the resonant frequency introduced by digital time delay. Moreover, the analysis in this paper proves that the existing virtual RC damper method is a special case of the proposed method. The parameter design principle for the RLC damper is also investigated. The analysis and the effectiveness of the proposed scheme is verified with simulation results.

This paper presents a nine-level inverter topology for an open-end induction motor drive requiring only eight switches per phase, using two three-level inverters with two isolated dc links in a 3:1 ratio. A space-vector-based formulation is used to determine pole voltages such that both inverters supply power to the load over the full modulation range, eliminating the possibility of dc bus overcharging. Proper selection of switching states ensures that all floating capacitor voltages are kept tightly balanced. A digital state machine is used to select sequences of switching states in order to eliminate deadtime-induced pole voltage transients, further improving the output-voltage quality. A level-shifted carrier-based pulse width modulation scheme is used. The steady-state and transient performance of this topology were verified and the experimental results are included.

The aerospace industry is facing challenges similar to that of the automotive industry in terms of improving emissions, fuel economy, and also cost. The increasing use of electrical and electronic features to improve vehicle performance, fuel economy, passenger comfort, safety, and convenience has resulted in the growth of electrical loads in automobiles. The potential electrical loads include the engine cooling fan, engine coolant pump, active suspension, electric assist power steering, electrically heated catalytic converter, electric power take-off, electric brake-by-wire, heated windscreen, telematics, and navigation. The U.S. government's current rules for the Corporate Average Fuel Economy (CAFE) program mandates an average of approximately 29 mi/gal, with a gradual increase to 35.5 mi/gal by 2016 (39 mi/gal for cars and 30 mi/gal for trucks). This will increase to 54.5 mi/gal starting from the 2025 model year. The electric, hybrid/plug-in hybrid vehicles, and fuel cell vehicles are considered the solutions to meet the above challenges.

In this paper, a high-temperature, high-frequency, wire-bond-based multichip phase-leg module was designed, fabricated, and fully tested. Using paralleled Silicon Carbide (SiC) MOSFETs, the module was rated at 1200 V and 60 A, and was designed for a 25-kW three-phase inverter operating at a switching frequency of 70 kHz, and in a harsh environment up to 200 °C, for aircraft applications. To this end, the temperature-dependent characteristics of the SiC MOSFET were first evaluated. The results demonstrated the superiority of the SiC MOSFET in both static and switching performances compared to Si devices, but meanwhile did reveal the design tradeoff in terms of the device's gate oxide stability. Various high-temperature packaging materials were then extensively surveyed and carefully selected for the module to sustain the harsh environment. The electrical layout of the module was also optimized using a modeling and simulation approach, in order to minimize the device parasitic ringing during high-speed switching. Finally, the static and switching performances of the fabricated module were tested, and the 200 °C continuous operation of the SiC MOSFETs was verified.

THE MARKET FOR INTEGRATED power systems for more electric aircrafts and, in particular, for unmanned air vehicles (UAVs) is rapidly developing [1]. Due to space constraints, a practical solution for UAVs is to employ electric-starter generators (ESGs) embedded in gas turbine engines to facilitate electric engine crank, assist the engine in reaching the desired idle speed, generate power to drive the onboard auxiliaries, and improve the overall efficiency of the system [2]. To control the ESG, a position sensor is required for the closed-loop control of speed and torque. However, the traditional sensors that provide accurate knowledge of the machine rotor position to facilitate precise control of the ESG cannot be used because of adverse operating conditions.

In transportation applications, lower weight and volume of the power conversion systems is very important to achieve high power density, high efficiency, and superior performance. The thermal management of these power conversion units plays a significant role in reducing the weight and volume. The use of superconductive motors/generators, degaussing coils, energy storage modules, and cables has been considered to increase power density and efficiency. High-temperature superconducting (HTS) components combined with cryogenic power converters will provide significant benefits in the electrification of transportation and high power density power conversion systems. Cryogenic power converter modules offer other promising benefits over their room temperature counterparts in terms of reduced size and weight (i.e., increased power density) and improved efficiency, switching speed, and reliability. Such an integration could result in significant weight and space savings for next-generation mass transportation systems. In this article, the current research on cryogenic power electronics and superconducting motors/generators is discussed for future aircraft and ships.

In this paper, the current status and the requirements of primary electric propulsion components-the battery, the electric motors, and the power electronics system-are reviewed. The future trends in the electric propulsion systems, battery charging, and the types of power trains are presented. Possible future electric vehicle powertrain systems based on lithium air battery and plug-in fuel cell vehicles are also discussed.

High-temperature (HT) converters have gained importance in industrial applications where the converters operate in a harsh environment, such as in hybrid electrical vehicles, aviation, and deep-earth petroleum exploration. These environments require the converter to have not only HT semiconductor devices (made of SiC or GaN), but also reliable HT packaging, HT gate drives, and HT control electronics. This paper describes a detailed design process for an HT SiC three-phase PWM rectifier that can operate at ambient temperatures above 100°C. SiC HT planar structure packaging is designed for the main semiconductor devices, and an edge-triggered HT gate drive is also proposed to drive the designed power module. The system is designed to make use of available HT components, including the passive components, silicon-on-insulator chips, and auxiliary components. Finally, a 1.4 kW lab prototype is tested in a harsh environment for verification.

In more electric aircraft (MEA) systems, the adoption of electro-hydraulic actuators (EHAs) and electromechanical actuators (EMAs) requires a power-on-demand electrical power system with regenerative power management capability. This paper proposes an auxiliary power unit (APU) for power generation and management system to supply/absorb the highly dynamic power demand/regeneration from the EHA/EMAs. The proposed system utilizes an open-end winding induction starter/generator (OEWIS/G) to create a separate DC bus for the actuators without adding significant hardware installment to the system. During the entire flight mission, the regenerative power is recovered by one side of the OEWIG terminals; meanwhile, the power delivery to the main DC network of the aircraft electrical power system can be independently controlled by using the same generator through the other side of the terminals. A closed-loop control scheme based on field oriented control and instantaneous power theory is developed to regulate both the main DC bus voltage and the electric actuation DC bus voltage simultaneously in aircraft emergency power mode.

In this paper, a controller capable of simultaneously providing both peak-load shaving and capacity firming required by renewable energy sources is proposed. This controller is designed to combine power/energy from multiple energy storage systems, including unidirectional systems such as fuel cells. Quick response energy storage systems such as ultracapacitors meet the requirements of initial fluctuations in power, and slower response systems provide the power for extended periods of activity. The rate of response of each energy storage system is a parameter known to the control system. The proposed algorithm improves the overall system's performance in terms of fast response, smart energy management, and ability to manage different energy storage and unidirectional/bidirectional sources. Simulations verify the operation of the control strategy in peak shaving mode and in steady state mode that can extend for a longer duration. Results show preferential power allocation to the quick response energy storage system, and limited power fluctuations on other sources.

For controls of proton exchange membrane (PEM) fuel cell (FC) systems, it is desirable to achieve accurate tracking of desired net output power with optimal oxygen excessive ratio (OER). In this paper, a cascade control framework is proposed for the FC output power tracking problem, which is a sequential combination of a multi-input-multi-output (MIMO) robust nonlinear non-interacting (RNNI) controller and a nonlinear disturbance-decoupling (NDD) control scheme. Two major issues are addressed: one is interaction/coupling between the OER and the net output power, and the other is the parametric model uncertainty caused by fluctuations in stack temperature under various operating conditions. Simulation results show that good tracking performance is obtained with the two performance objectives well decoupled, and furthermore the impact from the parameters uncertainty can be removed via a nonlinear compensator.

Multi-Agent System (MAS) architecture is a widely investigated topic for application in distributed control for power system operations. The key quality of MAS is its communication which must be versatile for any MAS based control. In this paper, a new communication algorithm for MAS based on Peer to Peer (P2P) communication agreeing to FIPA (Foundation of Intelligent Physical Agents) specifications is proposed. The proposed scheme has reduced communication steps, reduced burden on agents, and has very fast response compared to other existing P2P and Non-P2P architectures. This scheme is applied for a classic economic dispatch problem based on gradient search optimization and the simulation results are presented.

Open-end winding topology with a common DC source has path for zero-sequence current. Zero-sequence current needs to be suppressed because it does not contribute to the drive torque but has harmful effects such as loss and torque ripple. Both inverter and motor have sources of the zero-sequence component. The zero-sequence source on the inverter side is the voltage error due to dead time in switching. The zero-sequence source on the motor side is the zero-sequence component of the back EMF which consists of the third harmonic. In this paper, the two zero-sequence sources are investigated both theoretically and experimentally for an open-end winding induction motor drive system, and a method to suppress the zero-sequence current suppression is proposed. The voltage error is compensated by feedforward to the reference voltage. The zero-sequence component of the back EMF is compensated by a proportional and resonant controller because its frequency is known while its amplitude and phase offset are unknown.

The open-end winding machines can be fed by two three-phase inverters. In each phase, three-level voltages are generated by an H-bridge. Three-level PWM can reduce current ripple in α-β frame by using the voltage vectors on the vertices of small triangle. For open-end winding configuration, PWM methods which use the small triangle have been implemented with space vector modulation based techniques. These techniques modulate the voltage by switching one inverter while clamping the other inverter. To distribute switching stress, the role of switching and clamping are alternated between the two inverters based on the area in α-β frame. However, the switching stress is still concentrated to one inverter in low speed because the role change depends on the electrical angle. In this paper, a PWM method which uses the small triangle without clamping the output of inverters is proposed. The method is implemented with carrier based technique. It is realized by alternating two carrier waves which have 90° phase difference depending on the polarity of the reference voltage. The experimental results show that the proposed method can reduce the α-β current ripple as well as the conventional method with clamping.

This paper presents a nine level inverter topology with only eight switches per phase, for driving an induction motor with open end stator winding. The topology consists of two three-level, three phase inverters connected to the two ends of the induction motor. With asymmetric DC link voltages in a ratio of 3:1, an effective nine level space vector structure is realised. Modulation is done using level shifted carriers, which requires only sampled values of the three phase voltage references. Switching state redundancies are used effectively to ensure that both inverters supply real power to the load over the entire modulation range preventing overcharging of the DC links. In case of a fault in one of the inverters, the faulty inverter can by bypassed and operation is possible using the other inverter. The topology was simulated using MATLAB/Simulink and experimentally verified over the entire linear modulation range. Experimental results validating the proposed scheme are included.

It is well known that single-phase pulse width modulation rectifiers have second-order harmonic currents and corresponding ripple voltages on the dc bus. The low-frequency harmonic current is normally filtered using a bulk capacitor in the bus, which results in low power density. However, pursuing high power density in converter design is a very important goal in the aerospace applications. This paper studies methods for reducing the energy storage capacitor for single-phase rectifiers. The minimum ripple energy storage requirement is derived independently of a specific topology. Based on the minimum ripple energy requirement, the feasibility of the active capacitor's reduction schemes is verified. Then, we propose a bidirectional buck-boost converter as the ripple energy storage circuit, which can effectively reduce the energy storage capacitance. The analysis and design are validated by simulation and experimental results.

This paper presents the design, development, and testing of a phase-leg power module packaged by a novel planar packaging technique for high-temperature (250°C) operation. The nanosilver paste is chosen as the die-attach material as well as playing the key functions of electrically connecting the devices' pads. The electrical characteristics of the SiC-based power semiconductors, SiC JFETs, and SiC Schottky diodes have been measured and compared before and after packaging. No significant changes (

Traditionally, electric generators, driven by an aircraft's main propulsion engines or by a gas turbine (GT) auxiliary power unit (APU), have supplied the electrical needs of commercial aircraft. In flight, the marginal efficiency of electric power generated by the main engines and their generators is at most 30-40%, whereas on the ground with the engines shut off, the average fuel efficiency of the turbine-powered APU is typically less than 20% and also has undesirable noise and gaseous emissions. As environmental concerns mount, aircraft manufacturers and others are challenged to reduce fuel consumption while simultaneously reducing emissions. Hence, there is a very strong interest in developing fuel cells for aerospace applications. In this article, we report the study results of usingsolid oxide fuel cells (SOFCs) in combination with a GTas a hybrid APU system for a commercial aircraft. The purpose of this feasibility study is to investigate the potential use of fuel-cell-based APUs for onboard power generation in future "more-electric" commercial aircraft. In this article, the modeling of the major components of the SOFC-GT power generation system, summary of the findings, challenges, and final recommendations are presented.

With the requirements for reducing emissions and improving fuel economy, automotive companies are developing electric, hybrid electric, and plug-in hybrid electric vehicles. Power electronics is an enabling technology for the development of these environmentally friendlier vehicles and implementing the advanced electrical architectures to meet the demands for increased electric loads. In this paper, a brief review of the current trends and future vehicle strategies and the function of power electronic subsystems are described. The requirements of power electronic components and electric motor drives for the successful development of these vehicles are also presented.

Extensive research done in the recent past has proven that power electronic converters and electric propulsion motors are extremely critical components for modern hybrid electric vehicle (HEV) propulsion applications. Therefore, it is essential that both the traction motor and the associated drive operate at their optimal efficiencies throughout the driving schedule. In typical HEV propulsion applications, the traction motor and the drive are used over the entire torque/speed operational range. In view of this fact, this paper aims at modeling the inverter and motor losses/efficiencies over typical city and highway driving schedules. The noteworthy losses within a typical three-phase dc/ac traction inverter, such as the switching and conduction losses for both the insulated-gate bipolar transistors and the antiparallel diodes, are modeled and simulated over the city and highway driving patterns. An induction motor (IM) is used for a medium-sized sport utility vehicle, which was modeled in the advanced vehicle simulator (ADVISOR) software. The significant IM losses that were considered in the study include the stator copper losses, rotor copper losses, and core losses. Thus, the average efficiencies of both the inverter drive and the induction traction motor are evaluated and summarized under city as well as highway driving conditions. Finally, based on the individual-model-based efficiency analysis, the overall traction motor drive system efficiency is estimated.

In this paper, a predictive torque control method using direct voltage vector selection (PTC-DVS) with zero-sequence current suppression for open-end winding induction machine is realized. A cost function based on torque error, stator flux error and zero-sequence current is utilized to provide optimal voltage vector selection. The proposed method is compared with conventional field oriented control using PI controllers, and it is shown that the predictive torque control method can achieve faster torque response than conventional method. By varying the weight of the zero-sequence current in the cost function, the system can operate using either 27 voltage vectors or 7 non-zero-sequence-producing voltage vectors.

In more electric aircraft (MEA) system, both AC and DC electric power with multiple voltage levels are required for various aircraft loads. This paper presents an induction generator based AC/DC hybrid electric power generation system for MEA. In the proposed system, a high speed induction starter/generator and a low speed induction generator are installed on the high pressure (HP) and low pressure (LP) spools of the engine, respectively. In generating mode of operation, all of the constant voltage variable frequency AC power is generated by the HP generator while the DC power demand is shared by both HP and LP generators. A control scheme is developed to regulate the AC load voltage and coordinate DC power generation between the two generators. The proposed induction generator based AC/DC hybrid generation system presents reduced hardware installment compared to existing AC and DC primary generation systems.

A hybrid power generation system is a combination of two or more power generation sources to best make use of their individual operating characteristics and to obtain efficiencies greater than that could be obtained from a single power source. These hybrid power sources can be a combination of a fossil fuel based plant and a renewable energy source as in a gas turbine combined with a high temperature fuel cell based system or a combination of two or more renewable energy sources, like wind and solar. In this paper, hybrid power generation systems with different combinations of fuel cells and renewable energy sources for microgrid applications are discussed. The hybrid systems discussed in this paper are: combined cycle operation of a solid oxide fuel cell (SOFC) and a micro turbine; Proton exchange membrane (PEM) fuel cell and wind turbine; combination of SOFC and PEM fuel cell; and SOFC and solar thermal power generation system. The advantages and limitations of these strategies are also presented.

The combination of deadbeat controller and open-end winding topology is effective for improving the response of current control of induction motor drive system. A deadbeat current controller achieves high gain by compensating the delay element of digital controller with current prediction and excluding it from the control loop. The response of a deadbeat current controller depends on the duration of the sampling period of the digital controller. Quarter carrier sampling which measures current and updates the reference voltage at the top, bottom and middle point of the carrier is applicable to the current control of the open-end winding because the winding of each phase is fed by an H-bridge. This method reduces the sampling period by half compared to the conventional half carrier sampling. However, the quarter carrier sampling for H-bridge has a problem that the current measurement at the middle point of the carrier is susceptible to switching noise. In this paper, a new deadbeat current controller for an open-end winding induction motor is proposed. The proposed method also updates the reference voltage every quarter carrier period but measures current only at the peak of the carrier. At the middle point of the carrier, predicted current with two-sample time-horizon is used for the calculation of the reference voltage instead of the measured current which is not available.

In a microgrid system, unbalance in the three-phase system is created due to single-phase loads and decentralized single-phase renewable energy sources. This unbalance can be compensated locally at the point of common coupling (PCC) using a three-phase four-wire grid tied inverter. This paper focuses on a comparative study of 3-phase, 4-wire inverter topologies to compensate for positive, negative and zero sequence components of the current injected into the grid. The function of this inverter is to inject power to the grid and additional active power compensation (APC) to support unbalance, load reactive power, and load neutral current. Performance analysis and control of these topologies are being compared to evaluate utilization of dc link, size, control, and ease of implementation. A qualitative comparison of the topologies is provided to illustrate the advantages and disadvantages of the analyzed systems. Simulation and experimental results are presented to support the analysis of 3-phase, 480V, 50kVA system. The experimental results validate the ability of the inverter to provide 4-quadrant control of each phase independently.

This paper presents a new space vector pulse width modulation(SVPWM) scheme to reconstruct phase currents using neutral point current sensing in three level T-type converters. For this purpose, zero vectors and offset vectors are replaced with complementary active vectors. These active vectors do not affect the resultant output voltage and the voltage balance at the neutral point of three-level T-type converters. Hence, the pulse widths of corresponding active vectors can be adjusted even at low speeds without additional switching losses and low frequency noise in the inverter. The modified switching patterns can easily be created without significant computational complexity. The proposed method is experimentally verified using Fuji T type IGBT modules, Texas Instruments TMS320F28335 and Spartan 6 systems.

This paper proposes a new vector based dead time compensation method for a three-level T-type converter. The origin of the dead time voltage error is analyzed in detail under different switch commutation processes and load conditions. Based on the dead time voltage error for each phase, an error voltage vector is defined to indicate the effect of the dead time on the reference voltage vector from vector synthesis point of view. To cancel the dead time error voltage vector, the reference voltage vector is adjusted accordingly based on load current directions. Different from the studies presented in literature, the operation of the proposed dead time compensation method can be extended to over modulation region. The effectiveness and the advantages of the proposed vector based dead time compensation method are verified by both simulation and experimental results.

This paper proposes a method for independent drive of two permanent magnet synchronous motors (PMSMs) fed by a single five-leg inverter (5LI) based on reducing peak current of common leg. The advantages of 5LI are reduced size, volume, reduced number of devices, and increased efficiency due to total lower losses. The conventional method that has been used for controlling two PMSMs sends a large amount of current through a common leg, so the peak current of common leg exceeds safe operating area of 5LI. In this paper, the method of reducing peak current of common leg strategy by reducing peak current of common leg for control of two motors using 5LI is presented. The novelty of the proposed controller and the simulation results are presented.

A hybrid power system consists of a combination of two or more power generation technologies to make best use of their operating characteristics and to obtain efficiencies higher than that could be obtained from a single power source. Since fuel cells directly convert fuel and an oxidant into electricity through an electrochemical process, they produce very low emissions and have higher operating efficiencies. Hence, combining fuel cells with other sources, the efficiency of the combined system can be further increased or extend the duration of the available power to the load as a backup power. In this paper, different types of fuel-cell hybrid systems and their applications are presented. An analysis of the combined cycle operation of a solid oxide fuel cell (SOFC)-microturbine is presented. A strategy for combining the thermophotovoltaic power generation unit and SOFC to obtain the hybrid power system that would have higher efficiency is proposed. The hybrid operation of wind power and solar power system with proton exchange membrane fuel cell is also presented.

In more electric aircraft (MEA), supplying constant voltage variable frequency (CWF) AC power to frequency insensitive loads (eg. wing de-icing system, galleys, etc.) in DC primary distribution system requires an AC-DC-AC conversion which adds losses and additional hardware installment to the system. This paper presents a novel open-end winding induction generation system supplying CWF AC power for MEA As a subsystem of an AC/DC hybrid generation system, this CWF induction generation system uses a series connected inverter-load topology without any energy storage device. A current oriented control scheme is used to regulate both AC and DC side voltages of the system without battery compensation. The proposed series connected induction generation system presents reduced hardware footprint compared to conventional shunt connected and battery compensated series connected induction generation system. The performance of the proposed system is demonstrated by simulation in MATLAB/SIMULINK.

In this paper, high bandwidth current control for an open-end winding induction motor is realized with deadbeat control. A deadbeat current controller achieves higher gain than a PI current controller by compensating for the error caused by the digital sampling delay. The response of a deadbeat controller is directly influenced by its sampling frequency, while that of PI controller depends on gain tuning. In this paper, a quarter carrier period sampling of current controller is proposed for control of an open-end winding induction motor. In the proposed method, the sampling frequency is doubled as compared with the conventional half carrier period sampling method. Thus, the frequency response of the deadbeat current control is improved with this quarter carrier period sampling. The validity of this high bandwidth current controller is verified by simulation.

Fault tolerant and survivable operation schemes for multi-level converters, that interface the grid and critical loads, have been gathering attention for enhanced reliability. In case short-circuit or open-circuit faults occur in one or multiple voltage cells, the space vector pulse width modulation (SVPWM) control algorithm has to be modified according to the available voltage vectors for survivable operation. This paper proposes a new fault tolerant SVPWM strategy based on offset vector insertion, which allows controlling the multilevel converter as a two-level converter. A robust offset vector locating algorithm, which finds the feasible offset vector in case of short-circuit and open-circuit conditions, is presented. A single voltage cell short circuit fault is demonstrated on a seven-level hybrid input-switched multi-level converter to prove the effectiveness of the proposed survivable scheme.

Introduction of dynamic pricing in present retail market, considerably affects customers with an increased cost of energy consumption. Therefore, customers are enforced to control their loads according to price variation. This paper proposes a new technique of Home Energy Management, which helps customers to minimize their cost of energy consumption by appropriately controlling their loads. Thermostatically Controllable Appliances (TCAs) such as air conditioner and water heater are focused in this study, as they consume more than 50% of the total household energy consumption. The control process includes stochastic dynamic programming, which incorporated uncertainties in price and demand variation. It leads to an accurate selection of appliance settings. It is followed by a real time control of selected appliances with its optimal settings. Temperature set points of TCAs are adjusted based on price droop which is a reflection of actual cost of energy consumption. Customer satisfaction is maintained within limits using constraint optimization. It is showed that considerable energy savings is achieved.

A hybrid control strategy for the energy management of the microgrid system consisting of a number of electric vehicles and other energy sources is proposed in this paper. The main focus of this paper is on optimal control of power flow by scheduling and demand side management of energy generation system and the load by utilizing electric vehicles' energy storage system. The features of a centralized control and distributed control are combined into the proposed hybrid control strategy to improve the efficiency and reliability of the microgrid system consisting of electric vehicle charging stations. Cost of power generation and value of load equations are presented to compute a “situational aware” power balance. Simulated results utilizing these equations are presented for a residential scale proof-of-concept system.

The More Electric Aircraft (MEA) technology is continually evolving and is being widely recognized as the future technology for the aerospace industry. The main objectives are to obtain high power and volume density, high efficiency, reliability, and ability to withstand harsh environments. The pneumatic and hydraulic systems are being replaced by electrical systems. Power Electronics is an enabling technology for the advancement of more electric aircraft systems. This chapter provides a brief description of the electrical power generation, conversion, and distribution in conventional aircrafts and in more electric aircrafts such as Airbus 380 and Boeing 787. More electric architectures, power distribution strategies, more electric engine concepts, and the effect of high voltage operation at high altitudes are also discussed. The More Electric Aircraft concept is being widely recognized as the future technology for the aerospace industry

This paper presents an input switched multilevel inverter topology for controlling a three-phase open-end winding induction motor drive. In this topology, DC link voltage obtained from a single voltage source is divided into `n' equal steps, and a single pole multi-throw (SPMT) configuration is used to select any desired voltage level from these possible `n' voltage levels. This is followed by H-bridge which can alternate the polarity of voltage obtained at its output and hence generating necessary ac voltage. One salient feature of this multilevel inverter drive system is that the number of switches used is greatly reduced compared with traditional neutral-point-clamped inverters and flying-capacitor inverters based systems. It is possible to obtain two additional voltage levels at the output by adding only two switching devices per phase. And the input switched inverter topology can be easily extended to obtain any desired voltage steps at the machine terminals. A hybrid modulation technique combining symmetrical sinusoidal PWM and traditional SPWM is also proposed. Circuit analysis, modulation technique and software simulation are illustrated with respect to a seven-level input switched inverter drive system.

This paper proposes a novel multiple-input bidirectional DC-DC power converter to interface more than two dc sources of different voltage levels. This finds applications in distributed energy resources (DER), micro grid, and hybrid electric/fuel cell vehicles, where different dc sources of unequal voltage levels need to be connected with bidirectional power flow capability. Converter can be used to operate in both the buck and boost modes with bidirectional power control. It is also possible to independently control power flow when more than two sources are actively transferring power in either direction. This paper presents a power converter topology based on three switching legs of a standard 3-phase inverter module. The operation, analysis and design of the converter are presented with different modes of power transfer. Proposed converter is demonstrated for fuel cell vehicle application using real-time hardware-in-the-loop system. Results for a 5kW system are presented validating the theoretical analysis.

Open-end winding machine configuration provides better fault tolerance and flexibility for control compared with a conventional three-phase neutral connected electric motor. In this paper, three types of pulse width modulation (PWM) schemes - sinusoidal PWM, space vector PWM, and symmetrical sinusoidal PWM for open-end winding induction motor drives are being examined. The three PWM schemes are simulated in MATLAB/Simulink environment and their harmonic spectra are investigated for a 5.5 kW open-end winding induction motor. The current ripple under each PWM method is analyzed. Finally, the optimal switching strategy is discussed based on harmonic content, switching losses, and current ripple.