Boost斩波器在功率源负载下的动态特性与控制方法

为更方便、经济地研究分布式发电单元的电特性,可用Boost斩波器对发电单元直流特性进行模拟。分布式发电单元在功率变化过程中的直流特性较为复杂,因此在功率源负载下将Boost斩波器的二阶非线性状态方程近似线性化,并根据其特点采用输出反馈控制法,对输出电压和电流分别加以调节。由于采用数字控制,故对斩波器及控制器离散化模型进行了详细分析,根据稳定性判据得出控制参数取值范围。给出并分析了斩波器在恒功率、恒压、变压变功率情况下的实验波形,验证了该控制方法的有效性。

Dynamic characteristics and control of Boost chopper with power source load

To study the electric characteristics of distributed generation unit more conveniently and economically,the Boost chopper is used to simulate its DC link.As the characteristics of DC link are complicated during power change,the 2nd-order nonlinear state equations of Boost chopper with power source load are approximately linearized and the output feedback control method is adopted to regulate output voltage and current respectively.The digital control is adopted and the discrete models of chopper and controller are analyzed in detail.The ranges of control parameter are obtained based on stability criteria.Different experimental waveforms (constant power,constant voltage,variable voltage and variable power)are given and analyzed, and the results validate the correctness of control method.