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Battery storage system (BSS) integration in fast charging station (FCS) is becoming popular to achieve higher charging rates with peak-demand shaping possibility. However, the additional conversion stage for integrating the BSS increases the system losses, size and cost. The concept of partial power processing converter (PPPC), can mitigate this effect. Compared to conventional used full power processing converter, PPPC reduces the amount of transferred power from the BSS to the electric vehicle by the converter. As a consequence, the power losses generated by the converter are reduced, leading to lower sized converters and higher system efficiencies. This paper proposes a DC/DC multiport converter which allows the integration of battery storage in FCS based on a partial power processing concept, while maintaining the specific requirements in terms of isolation for FCS. The proposed three-port partial power processing converter (3P-PPPC) is derived from the commonly used triple active bridge (TAB) converter. The resulting design trade-offs, the dynamic behavior and limitations of the topology are investigated. Furthermore, the round-trip efficiency of the 3P-PPPC for integrating BSS in FCS is compared with conventional full power processing converter solutions, highlighting the superiority of the proposed topology. A prototype has been built to validate the 3P-PPPC.

High penetration of distributed generation (DG) has led to frequent voltage fluctuations in the distribution network. This paper describes the design of a partially rated, power-electronic-assisted onload tap-changing (OLTC) autotransformer. Positive and negative compensation of the grid voltage can be achieved on feeders that have high distributed generation and/or loading. A novel design of taps comprised of several no-load switches and a single semiconductor-mechanical hybrid switch have been proposed, that requires reduced voltage rating and a number of switches. In steady state, the mechanical switch in the hybrid switch conducts the load current resulting in low steady-state losses. During the tap change process, the OLTC uses semiconductor switches, namely insulated-gate bipolar transistor /metal-oxide semiconductor field-effect transistor, thus achieving arc-free tap change and long lifetime of switches. The OLTC system has been customized for both low-voltage and medium-voltage three-phase distribution networks. An open-delta configuration for the medium-voltage application has been proposed that requires only two OLTC units to control all three line voltages. Simulations are carried out to verify the steady-state and transient operation of the proposed OLTC.

This paper presents the preliminary design and functional testing of an electro-mechanical de-icing system for avionic applications. In particular, technology related aspects of optimum component selection for satisfying stringent performance and reliability requirements are discussed, in view of the particular features of the application.

This paper presents a novel hybrid direct power converter (HDPC) which overcomes the two main disadvantages of matrix converters: limited voltage transfer ratio and low immunity to grid disturbance. The proposed converter is formed by integrating a reversible auxiliary boost converter in the dc link of the two-stage matrix converter. Therefore, the HDPC can provide unity voltage transfer ratio even in the case where the supply voltage is highly unbalanced. The proposed converter also preserves most of the inherent advantages of the conventional matrix converter such as: controllable input power factor, sinusoidal supply currents, and bidirectional power flow. A novel predictive current control technique for the HDPC is also proposed for minimum energy storage in the converter. Important aspects of design, control, and implementation of the new HDPC are presented including theoretical analysis and simulations. Experimental waveforms at unity voltage transfer using a laboratory prototype are presented to confirm the viability of the proposed idea.

Direct power converters (DPC), which has no energy storage, the converter output voltage capability is affected when the input voltage is unbalanced. This paper proposes the utilization of the clamp capacitor, which is normally needed to protect a DPC, to extend the operating range of a two stage DPC during unbalanced supply, preserving its theoretical output voltage capability. A comprehensive simulation study with analytical explanations justifies the proposed method. Experimental results using a laboratory prototype confirms the viability of the proposed active compensation technique