首次提出了电压源高频交流环节AC/AC变换器电路拓扑族，这类电路拓扑由输入周波变换器、高频变压器、输出周波变换器构成。分析研究了这类变换器稳态原理与移相控制策略，绘出了变换器的外特性曲线。这类变换器具有电路拓扑简洁、两级功率变换(LFAC/HFAC/LFAC)、双向功率流、高频电气隔离、网侧电流波形可得到改善、负载适应能力强等优点。PSPICE仿真波形充分证实了这类变换器的正确性和先进性。

A novel combined soft switching technique and a novel circuit topologies family of the static inverter with high frequency pulse dc link are proposed in this paper. The topology structure is constituted of isolated high frequency pulse DC link circuit and DC/AC inverter. In order to overcome the duty cycle D of the one transistor forward mode Static Inverter less than 0.5 and the circuit topology of the interleaved forward mode Static Inverter more complicated, the duty cycle extension of high frequency pulse DC voltage is proposed in this paper. The steady operation principle of the active clamp forward mode high frequency pulse dc link static inverter with duty cycle extension and the control strategy of three-state discrete pulse modulation hysteresis current are deeply investigated. The design criteria for the key circuit parameters are gained. By using combined soft switching technique and the duty cycle extension of high frequency pulse DC voltage, a designed and developed 750VA 27VDC/115V400HzAC prototype has the advantages such as high efficiency, high power density, high reliability, high steady precision, fast dynamical response, strong ability of over-load and short-circuit, and low THD of output voltage.

提出了一类新颖的不间断高功率因数交流开关电源电路结构与拓扑族。这类交流开关电源，由单级不间断高功率因数AC-DC变换器与DC-AC逆变桥级联而成，前级采用电压型PWM控制技术，后级采用三态DPM电流滞环控制技术。分析研究了这类交流开关电源的三种工作模式和稳态原理。试验结果表明，这类交流开关电源具有拓扑简洁、功率密度高、不间断供电、功率因数高、动态响应快、过载和短路能力强、输出波形THD小等优点。

A combined three-phase inverter based on the duty cycle extended active clamp forward mode inverter with high frequency pulse dc link is proposed in this paper. The three phase inverter is constituted of three same single inverter modules. The voltage-mode feed forward control strategy is introduced in the active clamp forward mode high frequency pulse DC link circuit, the three-state discrete pulse modulation (DPM) hysteresis current control strategy is introduced in the inverter. The circuit topology, steady principle, control strategy, load characteristic, criteria for the key circuit parameters of the combined three-phase inverter are deeply investigated. A designed and developed 3kVA 27VDC/200V400HzAC prototype has excellent comprehensive performances such as small bulk, lower weight, high conversion efficiency, high steady precision, wide input voltage range, low THD of output voltage, strong over-load and short-circuit ability, and strong ability with different nature load and unbalanced three-phase load.

A novel circuit topologies family of the current mode AC/AC converter with high frequency ac link, based on Flyback converter, are proposed. These circuit topologies which can transfer one unregulated sinusoidal voltage with high THD into another regulated constant frequency sinusoidal voltage with low THD, are constituted of input cycloconverter, high frequency storage transformer and output cycloconverter. The circuit topologies family include single four-quadrant power switch mode, push-pull mode, half-bridge mode,and fullbridge mode circuit. The single four-quadrant power switch mode and push-pull mode converter are suit for low input voltage fields, but the half-bridge mode and fullbridge mode converter are suit for high input voltage fields. The operational mode, steady principle and transient voltage feedback control strategy of the kind of converter are investigated. The output characteristic curve, its relation to internal resistance, and the design criterions for the key circuit parameters are given. The current mode AC/AC converters with high frequency ac link have the advantages such as simple topology, two-stage power conversions, bi-directional power flow, high frequency electrical isolation, good line current waveform, strong load adapting ability. The correction and advance of the converters are verified by the Pspice simulation and test results.