考虑PT断线故障的同步发电机励磁控制策略  

Control strategy for synchronous generator excitation system considering PT breaking fault

作　　者：凡绍桂 段建东[1] 孙力[1] FAN Shao-gui;DUAN Jian-dong;SUN Li(School of Electrical Engineering and Automation,Harbin Institute of Technology, Harbin 150001,China)

机构地区：[1]哈尔滨工业大学电气工程及自动化学院

出　　处：《电机与控制学报》2019年第5期1-9,共9页Electric Machines and Control

基　　金：国家自然科学基金(51507039)

摘　　要：针对数字励磁控制器出现电压采样PT断线而导致的电压失控问题,提出一种具有高动态品质特征的电压测量与励磁控制技术。PT断线时,由三相测量模式自动切换到单相测量模式。为适应发电机频率波动及电压畸变,采用电压自平方单相电压检测方案。然而单相电压采样带来的采样延时会导致原PID参数达不到理想的动态效果。对此,提出一种具有发电机绕组稳态压降估计的滑模控制器,提高了发电机系统对系统参数的鲁棒性,可使励磁系统具有较高稳态精度与较快动态性能。在10kW数字励磁同步发电机上实验验证了所提电压采样技术以及励磁控制技术的有效性。To solve the problem of synchronous generator uncontrollable voltage caused by the broken of voltage sampling PT, the high dynamic quality voltage measurement and excitation control technology was proposed. When the PT broken fault occurs, the measurement system will automatic switch from three-phase measurement mode to single-phase measurement mode. To adapt to frequency fluctuation and voltage distortion, the RMS value of phase voltage was obtained by using the voltage square single-phase detection technique. However, the sampling delay caused by single-phase measurement will result in poor dynamic performance when the excitation controller has fixed PID parameters. To solve this problem, a sliding mode controller with the estimation of steady state voltage drop of generator winding was proposed. With the proposed control method, the system has high steady-state accuracy and fast dynamic performance and strong robustness to generator system model. The effectiveness of the proposed redundancy voltage sampling technique and the excitation control technique is proved by a 10 kW synchronous generator system.

关 键 词：励磁控制器 PT断线故障 单相电压测量 滑模控制器 

分 类 号：TM314[电气工程—电机]