Digital Control Technology Of The Sin Wave Invert Power Supply

Invert power is the main part of UPS. It also can be used as the emergence powers in hotels, power cars, ships and some other industrial areas. In some mountainous areas without enough power supply, it has a widely application field. The current products mostly are controlled by analog circuit. It has some problems. According to these problems, this paper does some research on the digital control on it with DSP-TMS320LF2407A.This paper introduces the achievement of the digital control on the 50Hz invert power in detail. It respectively uses several control methods to make theoretical analysis and experiment research such as state feedback control, iteration control, PID control and dead beat control.Firstly this paper builds the inverter model. Secondly it makes theoretical analysis on feedback control, iteration control, PID control and dead beat control. With the result, a hardware circuit is designed based on TMS320LF2407A. According to the experiment device, the control parameter is designed. Thirdly, the software is designed with the control method and debugged on the experiment device.The experiment device uses the single phase full-bridge invert circuit. The output power is 1KW, the switch frequency is 40kHz. With state feedback control and iteration control, it achieves the digital control; the output characteristic fulfills the demand basically. With the simulation and experiment, it finds that with the iteration control the surge occurs badly when the system is without load. The system is in stable state with full-load. The main factor is that the robustness is dissatisfied. This method needs improvement. With the state feedback control it has got a satisfactory result. In aim to reduce a capacitance current transducer, it uses the state feedback control with incomplete differential coefficient. With the testify of the simulation and the experiment, this method is feasible and it has the ability to suit to the load. The control method is achieved on the inverter with the 1kW power, the 220V output voltage the 50Hz frequency.