The Design Of SPWM VVVF Power Supply Based On DSP

Variable—frequency technology is a key component of the power electronics technology, which has a wide range of applications, including AC motor speed control and power supply, and many other important areas.This thesis presents a VVVF power supply systems based on DSP(Digital Signal Processor TMS320LF2407). First it introduced the topology and the principle of variable frequency power supply, and then the main circuit based on the Mitsubishi IPM (Intelligence power module) is presented, including the rectifier circuit, inverter circuit and the output filter. After analyzing basic principle of SPWM, this thesis proposes a modified version of rule sampling method. And also it analysis dead-time effect in PWM inverter, and two kinds of compensation methods are proposed.The hardware structure of VVVF power supply system controller based on DSP has been presented, referring to the research achievement inland and aboard. The real-time performance and reliability, as well as compatibility of controller have been analyzed in detail. The PLL circuit has been designed in the controller to meet the requirement of high-speed and accurate sampling. In order to meet the requirement of dead-time that IPM demands, independent hardware circuit for generating dead-time is designed in this thesis.The software design of controller is divided into Man-machine interface program and control program. The Man-machine interface program is composed of the display about real-time data and waves of the three-phase voltage and current, as well as the control variable; the control program includes the sampling and signal analysis, the modulation and triggering of signal and PI controller. At last, this thesis detailed the program design ideas and implementation process. .Finally, the thesis gives some photos of VVVF power supply system as well as the experimental results .Some improvement opinion are also presented.