This work presents a two-stage auxiliary power module (APM) for electric vehicle applications. The proposed architecture comprises a partial power converter (PPC) operating in step-down mode, interfacing with the high-voltage (HV) battery, and a half-bridge converter with an isolated current doubler (HB-CD) operating at a fixed conversion ratio (DCX), which ensures the galvanic isolation required in such applications. By employing the PPC as a pre-regulator, the HB-CD stage operates with reduced voltage across its semiconductors, allowing the use of devices with lower on-state resistance, thereby significantly reducing conduction losses, which are identified as the dominant source of loss in this context. Moreover, the fixed duty cycle operation (D = 0.5) guarantees zero-voltage switching (ZVS) on both the primary and secondary sides of the HB-CD stage, further improving overall efficiency. Simulation results validate the proposed strategy, demonstrating reduced voltage stress, full soft-switching behavior, and improved power conversion efficiency compared to a conventional single-stage architecture.

This paper presents a novel switched-capacitor (SC) series-connected partial power converter (S-PPC) for step-up voltage conversion. The proposed converter performs partial power processing (PPP) using a transformerless topology based on a capacitive coupled converter. As a result, it features low voltage stress on the semiconductors, offering higher efficiency and power density compared to the conventional boost converter. Therefore, this converter can be a suitable option for applications such as photovoltaic (PV) systems or battery-supplied systems. To validate the principle of operation and efficiency, a 3.5 kW prototype was built. It achieved a peak efficiency of approximately 99.0% near rated power, and maintained efficiency above 97.5% at low power (0.5 kW), operating at 200 kHz.

High step-up converters are often used in photovoltaic applications due to low voltage of photovoltaic modules. In this paper, a study of several voltage step-up cells added on primary and secondary sides of an isolated dc-dc SEPIC (single ended primary inductor converter) is made, in order to increase its static gain and synthesize a family of converters. To perform this study and select the most appropriate resulting converter, theoretical and comparative analyzes are accomplished. They include a brief description of each converter, tables and curves with relevant information, such as voltage gain, voltage stresses and component count, and the identification of the use of coupled inductor or transformer based on the analysis of dc magnetizing current. Moreover, theoretical analysis and experimental results on a 50 kHz and 200 W prototype of selected isolated SEPIC with voltage doubler cell are presented to validate the proposed topology and concept.

This paper presents a single-phase voltage distribution static synchronous compensator which integrates a single-phase to three-phase four-wired transformer-less conversion. Beyond that, this structure are capable to interface a distributed alternative energy generation to the mains. The major advantage of this circuit is the combined operation capability, which is realized with a few switching components while preserve an interconnected grounded neutral from mains to three-phase terminals. The power electronic circuit is parallel connected to the single-phase grid and add two additional terminals, which together, form the three-phase four-wired grid. The resulting active power from the converter energy balance are absorbed/delivered from/to the mains while the reactive power are managed to provide its single-phase voltage compensation. The power system scheme as well as the proposed closed-loop control structure are presented in details. Simulation results are illustrated to validate the converter assembly.

This paper proposes a hybrid topology for ac power source (ACPS) application composed of a modular multilevel converter (MMC), operating as main amplifier, and a linear power amplifier (LPA), operating as correction amplifier. The MMC and LPA are associated in series. This way, it is possible to gather the modularity, reliability and higher efficiency provided by the MMC and the high waveform fidelity provided by the LPA. Additionally, it is possible to reproduce a voltage waveform with a high bandwidth and, differently from previous works, with a topology that requires a unique dc source for the main amplifier. The control of the MMC is implemented by controlling the inner current and the submodule capacitor voltages; meanwhile, the control of the LPA is responsible for defining the output voltage. Experimental results are presented to demonstrate the suitable performance of the proposed topology in terms of dynamic response, output waveform fidelity and efficiency.

This paper proposes a digital control system for a voltage-controlled D-STATCOM applied to single-phase low voltage distribution networks. This system is especially suited for long rural distribution lines with problems to comply with voltage levels standards. The voltage regulator consists of a single-phase voltage-source PWM (Pulse Width Modulation) inverter connected in parallel with the point of common coupling (PCC) through a second-order low-pass filter. The proposed control system is composed of three loops: an active damping loop, a control loop to regulate the PCC voltage and a dc bus voltage control loop. Experimental results are included to demonstrate the performance of the proposed system.