中文摘要：

针对传统的超声波电源功率调节存在开关损耗大、输入功率因数低等缺点，采用了一种基于数字信号处理器（DSP）的软开关移相（Phase—Shifted，PS）PWM的调功控制策略，通过在逆变侧改变同时导通两个脉冲的相位差来实现输出电压的控制。给出了主电路拓扑结构，分析了工作原理，进行了功率控制流程图设计，利用Pspice软件进行仿真。试验表明，采用软开关移相PWM功率控制方式能够实现输出功率的连续可调。功率开关器件零电压零电流通断软开关的实现，减小了器件的开关损耗，负载侧功率因数高，提高了整机效率。

英文摘要：

Because some weaknesses are found in traditional ultrasonic power regulating system, such as large switching loss and low input power factor, etc. In this paper, adopting a soft switching Phase-Shifted PWM power control strategy based on DSP, which achieve the control of output voltage through the side changes on the inverter and phase difference between the two pulses conducted at the switching can realize output power regulation continuously. The implementation of power switching devices Zero-Voltage-Zero-Current Switching soft switch mode reduces the switching loss of the devices, increases the low-side power factor, which improves the efficiency of the system.