无刷直流电动机的开环调速机械特性研究  

Research on the Mechanical Characteristics of Speed Regulation Without Feedback for Brushless DC Motor

作　　者：罗玲[1] 马瑞卿[1] 解恩[1] 谭博[1] 窦满峰[1] 

机构地区：[1]西北工业大学,陕西西安710072

出　　处：《微特电机》2009年第1期11-14,共4页Small & Special Electrical Machines

摘　　要：基于星形三相六状态工作模式的无刷直流电动机的等效电路和电压回路方程,对调节PWM占空比和调节直流电源电压两种调速方式的无刷直流电动机的开环机械特性表达式进行了推导。对一样机的两种调速方式开环机械特性进行了仿真和实验分析。仿真和实验结果验证了推导的机械特性表达式的正确性。调节PWM占空比调速时,空载和轻载由于电流不连续,机械特性较软,随着负载增加,电流连续,机械特性变硬。调节直流电源电压调速时,电枢电流始终保持连续,机械特性较硬。分析了PWM开关频率、电枢电感对机械特性的影响,所得结论为无刷直流电动机及控制器设计中相关参数的选择提供了理论依据。The mechanical characteristics expressions of brushless DC motor（ BLDCM ） with three phases Y -connected windings in six states operate mode were derived based on the equivalent circuit and voltage equations, when the speed was regulated without speed feedback by adjusting the PWM duty ratio of inverter and the voltage of the DC supply. The mechanical characteristics for a prototype of BLDCM were got and analyzed by the experiments and simulations with the two regulating speed means. The experiment and simulation results matched the mechanical characteristics expressions well. When the speed of the BLDCM was adjusted by modifying the duty ration of PWM, the speed droped rapidly during the no load and the light load situations owing to the discontinuous current, the speed droped slowly while the load became heavy and the armature current flows continuously. When the speed of the BLDCM was adjusted by regulating the DC supply voltage, the speed drops kept slow with the load increasing and no matter the load was light or heavy, since the armature current kept continuous from no load to heavy load. The effects of the PWM frequency and winding inductance on the mechanical characteristics were analyzed ,which was helpful for the design of the BLDCM and its controller.

关 键 词：无刷直流电动机 调速 机械特性 占空比 电枢电感 

分 类 号：TM33[电气工程—电机]