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There are a variety of transmission services in the electric power Internet of Things based on IPv6, In order to satisfy the different delay requirements of different transmission services, a time sensitive routing strategy based on flow label is proposed. The strategy analyzes the transmission delay and packet loss rate, so that routing can choose more efficient and more suitable transmission link. The simulation results show that this strategy can effectively reduce the packet loss rate while satisfying the transmission delay.

This paper presents a high voltage level shifter with a dVs/dt noise immunity improvement structure. Benefit from the proposed slope sensing technology, the dVs/dt noise can be eliminated without compromising the transmission speed of the level shifter. Meanwhile, a new level shifter featuring with three branches is also proposed to increase the transmission speed. Based on 200V BCD process, measured and simulated results are performed to verify the electrical characteristics of the designed gate drive circuit.

This paper presents a hierarchical optimal dispatch of the electric vehicles (EVs) and thermostatically controlled loads (TCLs) in micro-grid. In the proposed framework, The EVs are aggregated as physical energy storage and the TCLs are aggregated as virtual energy storage. At the bottom level of the proposed model, aggregators optimize the dispatch of EVs and TCLs based on their individual information. At the top layer, wind power and thermal generators are centrally scheduled based on the conventional market-clearing model. The IEEE 30-bus system is used to verify the proposed framework. Simulation results reveal that the scalability issue of single-level centralized dispatch can be well addressed and reduce the emission in whole system. The combination of the EVs and the TCLs also brings economic benefits as well.

New challenges are presented for reliable operation of the power system due to increasing penetration of distributed generations (DGs). The low inertia of the generator and their power electronics interface decoupled from the grid makes it much more difficult to maintain system stability, especially for islanded micro-grids. To ensure the power quality and system reliability, the accurate and effective detection of transient signals is required. This paper utilizes wavelet transformation to detect and classify the transient signals in islanded micro-grids. The results show that the disturbances are successfully identified by applying wavelet transform in both simulation and experimental conditions. The classification of disturbances was also investigated. Coefficient spectrums and histograms are plotted to identify different disturbances in the micro-grid.

Micro-grids are envisaged as single plug-and-play electrical systems that can operate either in grid-connected or islanded modes. Their main sources of power are renewable and are usually integrated through power electronic devices. These present new challenges to reliable operation of the system due to their inherent incapability to regulate the system. Transients in the micro-grid make it further vulnerable. The transient signals only occur for a few cycles and cannot be easily detected directly in the time domain. This paper utilizes wavelet transformation method to detect and analyze the transient signals in the micro-grid. The results show that the disturbances are successfully identified in both grid-connected and islanded modes, by applying wavelet transform. The variation of coefficients is found to be much smaller in grid-connected mode.

An architecture for low-noise spatial cancellation of co-channel interferer (CCI) at RF in a digital beamforming (DBF)/MIMO receiver (RX) array is presented. The proposed RF cancellation can attenuate CCI prior to the ADC in a DBF/MIMO RX array while preserving a field-of-view (FoV) in each array element, enabling subsequent DSP for multi-beamforming. A novel hybrid-coupler/polyphase-filter based input coupling scheme that simplifies spatial selection of CCI and enables low-noise cancellation is described. A 4-element 10GHz prototype is implemented in 65nm CMOS that achieves >20dB spatial cancellation of CCI while adding

All-digital PLLs promise flexible and precise FMCW radar signal generation for 77GHz radar applications. Such PLLs require digitally-controlled oscillators (DCO) with wide frequency tuning range (FTR) and high resolution to address a range of applications and low phase noise requirements. In this work, novel resonator structures with fine capacitance/inductance switching are embedded in a wide FTR common-source Colpitts DCO to achieve

Micro-grids are becoming very popular due to the plug-and-play nature of their integration. But the high penetration of distributed generators may also create potential instability as it is unable to regulate the system. This paper compares the dynamic performance of a micro-grid when the system load demand is suddenly changed. Multiple distributed sources are used to create a flexible simulation scenario. The simulation is carried out using DIgSILENT software and the results indicate that the micro-grid may collapse when it works in islanding mode. It is found that the installation of storage device can help solve this problem, but both generation and load changes should be considered when determining its capacity. The DG penetration level also shows the impact on the system transient as it can potentially change the level of disturbance. The results of the simulation are validated using an experimental micro-grid setup, having a mix of wind, solar generation and battery storage.

An adaptive Gaussian mixture model (AGMM) with variable component numbers is proposed for accurate speaker recognition. According to the cluster property of speaker's acoustic feature distribution, an absorb-merge-split mechanism is utilized to adjust the Gaussian component numbers during the model training to overcome over-fitting and under-fitting in traditional models. Therefore every speaker's AGMM models have different distribution component number. The experiment result shows the recognition accuracy of the proposed AGMM is greatly improved compared with the traditional Gaussian Mixture Model (GMM). The error rates of recognition with MFCC and Bilinear frequency cepstrum coefficients (BFCC) decline by 41.41% and 22.21% respectively in relative.

The increasing penetration of distributed generation (DG) into the electrical network presents new challenges to reliable operation of the system due to the special characteristics of DG units and their low inertia. This paper investigates the dynamic behavior of the system with multiple DGs. The main aim is to study the transient caused by the sudden integration of DG. The impact of the size of the storage device used is also considered in the paper. The simulation is carried out in DIgSILENT Power Factory 14.1 and a micro-grid setup in the laboratory is used for experimental validation. The results show that it is difficult for the micro-grid to maintain stability under a disturbance in islanding mode without any battery storage. The application of battery storage will considerably improve the micro-grid transient performance and the level of the DG integrated into the system is the critical factor that will determine the appropriate capacity of the battery.