【作者】 汪海燕；

【导师】 张敬华；

【作者基本信息】 合肥工业大学 ， 电机与电器， 2004， 硕士

【摘要】 永磁无刷直流电动机实际上是以电子换向代替机械换向的直流电动机，因而保持了直流电动机的优良特性，具有较好的起动和调速性能，又因它无需机械换向器使电机的结构简单，可以从根本上克服一般有刷直流电动机易于产生换向火花的弊病，在航天、机器人、数控机床等许多工业领域已得到广泛应用。 本文从永磁无刷直流电动机的基本工作原理出发，提出了利用自适应模糊PID控制器实现对永磁无刷直流电机调速系统进行设计的新方法。首先建立无刷直流电动机的动态数学模型，以此进行转速和电流双闭环调速系统控制；接着将模糊控制器和PID控制器通过自适应因子结合起来，在线自调整控制参数，进一步完善了PID控制器的性能，提高了系统的控制精度。同时给出了仿真结果。 此外，如何在较宽的调速范围内减小力矩波动一直是交流系统研究的主要问题。本文对双极性调制的无刷直流电动机仿真，分析了转速和调制频率对转矩影响；并综合考虑缓冲电路、控制死区及载波频率对PWM逆变电路中IGBT开关损耗的影响。同时给出了仿真结果。更多还原

【Abstract】 The permanent magnet brushless DC motor is a DC motor using electronic communication in place of mechanical communication in fact, so it has excellent characteristic of DC motors, for example good start and timing performance. It simplifies the motor’s structure and overcomes the friction disadvantages of ordinary DC motor because it doesn’t use mechanical communication. It is extensively used in aviations, robots, digital machine tool and so on.In the paper, a new approach of designing the timing system for brushless DC motor (BLDCM) is presented, which is based on the parameter’s self-adaptive PID controller combined with Fuzzy logic. At first, the principle of BLDCM is analyzed and the model is built; then a test is performed on a timing system of close loops of speed and current; Through combining Fuzzy logic with PID controller and adjusting control parameters in on-line ways, it can perfect the properties of PID controller and improve the precisions of control system. At the same time the results are given.What’s more, how to reduce the torque pulsation in a wide timing range is the main discussing issue of alternating servo system. This paper simulates and analyses the torque pulsation because of the modulation frequency and speed variation under ambipolar pulse width modulation; the influence of snubber circuit, dead time effects , and modulation frequency to IGBT PWM Inverterbridge is taken into account, too. At the same time the results are given.更多还原