晶闸管Marx发生器电路及充放电特性

Thyristor Marx Generator and Its Charging-Discharging Characteristics

为满足新兴工业对中小储能功率脉冲电源日益增长的需求,设计了一种采用晶闸管作为主开关的Marx发生器,它由脉动直流电源供电,增加晶闸管组合模块就可方便地扩展级数提高输出电压,晶闸管组合模块有对负载的单向、双向和续流3种放电工作模式。该设计改进了充电拓扑电路,并给出了充电电阻及其功率的计算方法,有效地避免了负载上的预脉冲,实现了各储能电容充电电流的一致,有效地抑制了环流和提高了充电效率。变负载放电特性分析表明,感性负载时减小电感的输出能使电流脉冲幅值提高、脉宽变窄,特性曲线为设计和用户的使用提供了依据;容性负载时储能电容的实际等效参数对小容量的电容放电参数有较大影响,有必要减小回路的总电感,以获取陡前沿电压脉冲和窄电流脉冲。感性及容性负载的实验放电波形与仿真结果比较相符。所设计的Marx发生器在工业应用中既可用来产生较强脉冲磁场,又可用来产生放电等离子体。

A thyristor Marx generator is designed for demands of developing industry. An AC single phase solid state voltage regulation module is used for adjusting AC supply voltage. The charging supply is gotten by a step-up transformer and a rectifier. It is easy to enlarge the output discharging voltage of Marx generator by increasing the stages of storage energy capacitors and switches consisting of thyristor module. There are three modes of discharge such as the unidirectional, bidirectional and freewheel ones in the different switching modes of thyristor module. The improved charging circuit design effectively avoids the pre-pulse on the load while charging. A method of selecting charging resistances is given for achieving high efficiency balance charging and circle current restriction, and another method to calculate the power of the resistances is given. The discharging characteristics indicate that reducing the inductance will get the higher amplitude and the narrower width of current pulses for inductive load. When the load is capacitive, the real equivalent serious inductance of storage capacitor plays an important part while the load capacitance is lower, and it is necessary to minimize the loop inductance to obtain precipitous edge and narrow pulse. The experimental discharging waveforms accord with the simulation ones. The thyristor Marx generator could be used in the applications of strong magnetic field and discharging plasma.