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This paper presents a control approach for a current driven Dual Active Bridge (DAB) converter used as an interface to transfer power between the grid and Electric Vehicles (EVs). The wide range of input voltage and load variation makes it very challenging to have a fast control response of power flow between the two dc buses. This control system adaptively regulates the frequency and the phase shift of the converter based on the operating condition.

This paper presents a new voltage control technique for grid-connected single-phase AC/DC converters. The proposed control system is able to significantly improve the performance of the closed-loop control system by using a nonlinear observer to extract the DC value of the DC-bus voltage. The proposed nonlinear observer is able to completely eliminate the impact of double-frequency ripple inherent to single-phase power conditioning systems in the closed-loop control system. Thus, a high bandwidth controller can be used to improve the performance of the control system. Simulation and experimental results demonstrate the superior performance of the proposed closed-loop control system compared to the conventional ones.

This paper presents a closed-loop control technique in D-Q rotating frame for bi-directional single-phase AC/DC converters. The proposed control system allows the active and reactive power control in both directions from grid to vehicle and vehicle to grid, while controlling the DC-bus voltage. Due to the lack of freedom degrees required for orthogonal systems, using the D-Q frame is a challenge in single-phase power conditioning systems. In this paper, an all-pass filter has been used to generate the orthogonal signals in the closed-loop control system. This method generates the orthogonal signals without degrading the dynamics of the closed-loop control system and with less noise in comparison to the other common methods such as differentiators. A DC-bus voltage estimator based on adaptive filter has also been used in this paper to remove the double frequency ripple and in turn increase the reliability and speed of the proposed controller. The proposed control scheme is used to implement the smart charging and power management strategies of the residential loads using electric vehicles as a storage system. Simulation and experimental results demonstrate the transient and steady-state performance of the proposed controller in different modes of operation. Also the performance of the proposed DC-bus voltage estimator in removing the double frequency ripple as well as the application of the proposed control scheme in implementation of power management strategies in a typical household, has been shown by using simulation results.

This paper presents a new voltage control technique for grid-connected single-phase AC/DC converters used in an energy storage power conditioning system. The energy storage unit is intended to be used in a single-phase distributed generation. The proposed control system is able to significantly improve the performance of the closed-loop control system of the converter by using a nonlinear signal processing technique to extract the DC-value of the DC-bus voltage. The proposed technique is able to completely eliminate the impact of double-frequency ripple inherent to single-phase power conditioning systems in the closed-loop control system. Thus, a high bandwidth controller can be used to improve the performance of the voltage control system. Simulation and experimental results demonstrate the superior performance of the proposed closed-loop control system compared to the conventional ones.

This paper presents a peak-current mode self-sustained oscillating control (SSOC) technique for a Dual-Active Bridge (DAB) DC/DC converter. The proposed control approach is able to significantly improve the performance of the bi-directional DAB DC/DC converter over a very wide range of operating conditions. Basically, the proposed PCM-SSOC scheme adaptively regulates the respective phase-shifts for each bridge, as well as the switching frequency of the converter for different operating conditions in order to achieve an optimal performance. In this control technique, the timing signal is produced based on the transformer primary current, which is a feedback to the control system to determine the switching instants of the power MOSFETs. Therefore, the control system automatically tunes the control variables for different operating conditions. Comprehensive mathematical analysis based on the geometric viewpoint of the control system of the proposed PCM-SSOC scheme is presented, which provides a very good insight into designing the control system. Experimental results provided from an experimental prototype confirm the superiority of the converter performance compared to the conventional fixed-frequency phase-shift control approach.

This paper presents a novel control approach to improve the dynamic response of wind energy control systems (WECS) that use a permanent magnet synchronous generator (PMSG) operating under a wide input and load range. In this paper, it's shown that WECS is classified as a Port-Controlled Hamiltonian (PCH) system. Therefore, a nonlinear controller based on PCH is proposed, which is able to robustly control the WECS under parameter uncertainties and disturbances. The performance of the PCH-based controller is evaluated through simulation. Also, the proposed controller is implemented on an experimental prototype. Simulation and experimental results show a robust and fast transient performance compared to the conventional dq-controller.

This paper presents sensorless techniques for a grid-connected voltage source inverter with an LCL-filter in order to improve the closed-loop control performance and reduce the overall cost of the converter through an observer-based control approach. The observability of the system is mathematically analyzed using the system state-space equations, and then two state observers are designed and the closed-loop performance of the observers is compared in detail. The observer-based controller is implemented on a grid-connected voltage source inverter. The experimental results demonstrate the feasibility of the proposed closed-loop control system and superior performance particularly in terms of noise susceptibility.

This paper presents a novel approach to control an AC/DC converter without using any current sensors. The AC/DC converter is based on the well-known boost PFC topology. Due to the particular structure of the boost PFC AC/DC converter, sensorless control of the converter is very challenging. As illustrated in this paper, the converter loses its observability for some operating points. This is the reason that the sensorless control of the boost PFC entails special attentions. A very simple and practical senseless scheme is proposed in this paper, which is able to accurately estimate the inductor current for the entire operating range of the converter. In addition, a very simple and practical closed-loop control approach is proposed in order to improve the transient response of the single-phase boost PFC converter. This approach eliminates the need for filtering double frequency ripple from the output voltage, which allows increasing the bandwidth of the external voltage loop. Simulation and experimental results validate the feasibility of the proposed technique and confirm its superior performance compared to the conventional control system.

High frequency transformers are one of the essential building blocks to provide galvanic isolation for power converters. Due to the switching nature of the converter, electromagnetic compatibility (EMC) of these converters is an essential requirement, to ensure not only its own operation but also the safe and secure operation of surrounding electrical equipment that are connected to same power distribution network. Thus, strict EMC standards such as CISPR 12 or SAEJ551/5 are imposed to provide safe and reliable operation of the power converters. Conventional passive filters used for EMI mitigation in power converters, comes at the expense of cost, size and weight, power losses and PCB real estate. In this paper, an integrated EMI filter embedded into the main high frequency planar transformer used in the DC/DC converter is proposed as a very cost-effective and efficient solution. The proposed structure is able to significantly suppress the Common-Mode (CM) EMI noise generated in the DC/DC converter. In order to evaluate the performance of the integrated transformer, a high frequency simulation through HFSS has been performed. Also, a prototype has been implemented to assess the feasibility of the proposed structure and confirm the HFSS simulation results. The results obtained from a 3KW prototype show that the proposed integrated EMI filter can effectively suppress the CM noise particularly for power converters operating at high switching frequency. The proposed structure can be a very simple and cost-effective EMI filtering solution for many applications such as future plug-in electric vehicle.