本论文采用晶闸管相控调压技术，提高异步电动机在轻载或变载运行时的经济性能。文中阐述了异步电动机调压节能原理，分析了电机降压运行对电机性能的影响以及电机允许降压范围跟电机负载率的关系。在此基础上，本文提出了一套以单片机为核心、以晶闸管为调压元件的异步电机节能控制器设计方案，给出了硬件和软件的具体设计思想。 系统采用嵌入式ATmega48单片机作为控制核心，设计了高压电气隔离、信号变送测量电路；针对输出功率调节，研制了基于定时计数器的晶闸管相控调压电路。软件采用模块化思想，完成了基于嵌入式芯片内部资源的功率因数检测、电流电压测量和带有功率调节功能的晶闸管闭环移相触发等程序设计；采用功率因数和电机电流为依据的双闭环调压算法，实现了系统的自动调压控制，提出了解决系统输出稳定性和快速性之间矛盾的新方法；在系统智能化技术研究方面，本文设计了能对多个被控对象实现远程监控的CAN通讯网络。 论文首先用MATLAB对设计的交流调压方案进行了仿真试验，为优化硬件电路设计提供了依据，也论证了该方案的可行性。按论文设计方案制作了一台功能样机，完成了硬件电路设计调试与软件编程，以380V/2.2kW的三相异步电动机为试验对象进行了实际加载性能测试，电机在空载运行时功率因数提高了164%、节电大约24%。

This paper adopts the technology of phase controlling voltage based on thyristor to increase asynchronous electromotor economical efficiency, analyzes the energy-saving principle of alternating voltage for asynchronous electromotor, discusses the influence of the voltage changing on motor’s performance and the allowing scope of regulating voltage with changes of loads. Based on these, the paper presents a scheme of energy-saving, which is cored as microcomputer and regulated by thyristor, and gives design ideas both of hardware and software. This system uses ATmega48 microcomputer as a core, designs high-voltage isolation circuits, signals converted and measured circuits, and the thyristor’s phase controlled circuits for regulating motor’s output power. The software adopts modular idea, designs power factor measured programs, voltages and currents of motor measured programs and thyristor triggered programs. This system adopts double close loops control of both power factor and current to realize automatically regulate motor’s voltages, puts forward the new way to reduce the conflict between stability and fast response, designs CAN bus which is conventional to realize remote measure and control. First, the paper uses MATLAB to simulate the regulating voltage scheme for testifying the feasibility and optimizing its hardware design. Then, we make one sample, have designed and debugged its hardware circuit and software, and have finished the loading performance test on 380V/2.2kW three asynchronous electromotor. The result shows this equipment saves 24.3% electricity quantities and power factor increases 164% when motor is running without load.