摘要
异步发电机组在小型水利发电中应用十分广泛,它具有价格低廉、控制简单、可靠性高的特点。但是,由于受负载和励磁电容的影响,异步电机输出的电压波动较大,电能质量较差。针对此问题,提出一种具有可变电容特性的H桥变流电路,使异步电机输出电压的稳定。该结构具有结构简单,控制方便,损耗小的特点。首先分析了负载和励磁电容对异步电动机的输出电压的影响;其次,从电容的充放电电量控制的角度,对该H桥变流器的电路结构、工作原理、数学模型进行分析。为了实现电压的最优控制,针对电流畸变率与电容电压峰值状态变化,采用模糊控制,对滞后电容电压和移相角参数动态调节,从而实现最优电压控制。最后,通过仿真实验验证了该电压控制方案具有良好的调压效果。
Asynchronous generator unit is widely used in small hydropower generation. It has the characteristics of low price, simple control and high reliability. However, due to the influence of load and excitation capacitance, the output voltage of asynchronous motor fluctuates greatly and the power quality is poor. In order to solve this problem, an H bridge variable current structure with variable capacitance is proposed to stable output voltage of asynchronous motor. The structure is simple, easy to control and low loss. The influence of load and excitation capacitance on the output voltage of asynchronous generator is analyzed at first. Secondly, from the point of view of charge and discharge power control of capacitance, the circuit structure, working principle and mathematical model of the H-bridge converter are analyzed. At the same time, in order to realize the optimal control of the voltage, the fuzzy control is used to adjust the hysteresis capacitance voltage and the phase shift angle parameters to realize the optimal voltage control for the variation of the current distortion rate and the peak state of the capacitor voltage. Finally, the simulation results show that the voltage control scheme has a good voltage regulation effect.
作者
侯希伦
孙宇轩
兰芳
戴帅龙
HOU Xilun;SUN Yuxuan;LAN Fang;DAI Shuailong(China Three Gorges University College of Electrical Engineering&New Energy,Hubei Yichang 443002,China)
出处
《电工材料》
CAS
2019年第6期43-47,共5页
Electrical Engineering Materials
关键词
异步发电机
电压波动
H桥变流器
模糊优化控制
asynchronous generator
voltage fluctuation
H-bridge converter
fuzzy optimal control
