励磁电流功率放大器数学模型及其稳定性研究

对励磁电流精确控制是发电机励磁系统的重要要求，本文对具有H半桥结构的励磁电流功率放大电器工作原理进行分析和仿真。建立了以H半桥励磁电流功率放大器和感性负载为对象的电流闭环控制数学模型，并在对模型进行合理简化基础上，根据根轨迹和劳斯判据理论推导PI调节器参数的稳定域，通过试验验证了PI调节器参数对系统稳定性能的影响。根据分析和试验对控制器参数进行调整，确定合理的PI调节器参数，实现励磁电流以较小的超调量和较快的响应速度稳定输出。试验结果表明了理论推导的正确性，该方法简单有效，具有一定的工程应用价值。

Research on Mathematical Model and Control Performance for Excitation Current Switching Power Amplifier

Accurate control of tke exciter current is an important requirement for excitation system of tke generator. For settling concussion of generator exciter current, the working principle of the H half-bridge excitation current switcking power amplifier is analyzed and simulated. Using H half-bridge excitation current switcking power amplifier and inductive load as project, matkematical model of exciter current closed loop control system is establisked. According to root locus and Routk criterion tkeory, stable region of PI controller parameter is derived based on simplified matkematical model, tkeoretical derivation is verified by experiments, and effect of PI controller parameters to system stability is analyzed. According to experiments result, parameters is adjusted to define rational PI controller parameters wkick realizes excitation current firm output with low excess and short rising time. The results of the experiments show the correctness of tke tkeoretical derivation wkich is valuable and easy to implement in practice.