同步发电机励磁电流放大器研究  

Research on the Excitation Current Amplifier for the Synchronous Generator

作　　者：张洪涛 吴世君[2] 

机构地区：[1]92132部队25分队 [2]92337部队

出　　处：《船电技术》2016年第4期1-6,共6页Marine Electric & Electronic Engineering

摘　　要：给出了励磁电流放大器所使用的Buck电路和电压双象限H桥功率主电路的工作原理,并针对后者分析了两路中心对称但占空比不同的PWM实现三电平工作方式(称为对称PWM法),同时提出了采用两路占空比相同但具有一定相位差的PWM控制方法以减小电流纹波(称为移相法)。给出了对称PWM法和移相法两种方式下的电流纹波计算公式,指出半周移相(180°移相)时电流纹波大为减小且几乎不受电源电压影响。利用Matlab对励磁电流放大器进行了仿真,构建了以DSP为控制核心的试验平台,并进行了发电机励磁调节试验。理论分析、数字仿真和试验结果表明,对不同工况下的纹波大小分析正确有效,试验所采用的励磁电流放大器调节性能优良。The working principle of the Buck and the voltage quadrant H bridge topology for the excitation current amplifier is described, and the method, called symmetrical PWM with two symmetric but different duty ratio pulse width modulation（PWM） is proposed in the paper, which makes the current amplifier work in three-level mode by using a fixed duty PWM signal and a verified duty PWM signal. Meanwhile, a proper control method which is of two same duty ratios PWM signals but different phase is proposed to reduce the current ripple（called shifting phase）. The computing function of the current ripple for the shifting phase method shows that there is almost no influence of source voltage at 180 degree phase shifting point. By using a practical DSP（digital signal processor） controlled current amplifier and the generator excitation regulation as an illustrative example, numerical Matlab simulation and experimental method are implemented. Experimental result shows that the ripple computing function is reasonable and the excitation current amplifier in the generator excitation regulation works with an excellent performance.

关 键 词：励磁电流放大器 电压双象限H桥电路 电流纹波 励磁调节 DSP 

分 类 号：TM351[电气工程—电机]