直驱风电系统直/直变换电路的设计与控制

Design and control of DC/DC converter in direct driven wind power system

风速低,直驱风电系统发电机输出电压较低;风速高,发电机输出电压又较高。为保证后接并网逆变器的正常运行,需要在整流后设置升压、降压变换电路,以控制施加到并网逆变器上的电源电压。阐述了直驱风电系统直/直变换电路的构成,详细分析了变换电路工作原理与控制方法,设计并构成了实际试验系统。系统实验运行结果表明:具备升降压功能的直/直变换电路可以实现输入电压的升降压变换,能够保证后续逆变器安全稳定运行。

The output voltage of direct driven wind generator is low when wind speed is low, and it is larger when wind speed is higher. The buck/boost converter is needed to promote or decline DC voltage, so as to control the voltage inflicted on the inverter, and ensure the inverter work normally. The constitution of DC/DC converter in direct driven wind generator was expatiated, the operation principle and its control method were analyzed in detail. The testing equipment was designed and worked out. The result of experiment show that, the converter can carry out promoting or declining voltage, and the safety operation of inverter can be guaranteed.