摘要：无刷直流电机有起动转矩大、响应速度快等优点，同时避免了传统直流电机换向器带来的不利影响，因此在电动车领域有着广泛的应用。无刷直流电机的正常工作离不开控制器的控制，本文设计了有位置传感器的无刷直流电机的双闭环PI调速系统。本文首先建立了无刷直流电机的数学模型，给出了动态结构图，并进行了参数整定。随后针对双闭环控制策略，用Simulink软件进行了仿真，并分析了仿真结果。本文还给出了控制系统的硬件设计方案，包括MOSFET驱动电路、供电电路、信号采集电路、逻辑转换电路等，并针对STC12C5404AD单片机进行了软件设计。硬件实验结果与理论分析和软件仿真一致。本文提出的无刷直流电机控制器经济实用，可以作为绝大多数低压电动车的电机控制器。
关键词：电动车；无刷直流电机；双闭环调速

Abstract: Aiming at the significant effect on total pressure, flow and power of fan from atmospheric density over a wide range of altitude, threedimensional surface data of fans total pressure and flow, total pressure and power were built based on similarity principle of fan in arbitrary height and speed conditions. Fan characteristics over a wide range of altitude were simulated and analyzed. The relationship between fan characteristics and height, and the relationship of all the characteristics on the same height were researched. Fan characteristics are changes with altitude. By researching fan characteristics over a wide range of altitude, optimization control of fan efficiency was realized under the condition of considered the change of atmospheric density.
Key words: fan characteristics;atmospheric density;total pressure;flow;threedimensional model