Research And Realization Of The Cascaded High Voltage Inverter Based On DSP And FPFA

In recent years, as a new power converter, cascaded high voltage inverter isuesed widely in the application of power system and high voltage. However, by thepower switching devices of high-voltage frequency converter increases, andthe control precision is getting higher and higher, the control system of inverter putforward higher requirements, not only to ensure the switch trigger signal is safe andreliable, but also can realize the accuracy of real-time control for multi-channel. Tosolve these problems, the control system based on DSP and FPGA is designed andimplemented.From the research of high voltage inverter in the research background and theand the research status in china and abroad, the main structure type of thehigh-voltage inverter is analysised,and the characteristics of the cascade high voltageinverter used widely in present is mainly introduced.Then the CPS-SPWM (CarrierPhase Shifted Sinusoidal Pulse Width Modulation) technology is taked based on thestructural characteristics of the cascaded high voltage inverter.，and the technologyhas carried on the detailed mathematical analysis.In order to verify the effect ofCPS-SPWM modulation technology, the output characteristics of cascaded converterbased on CPS-SPWM technology is simulated by MATLAB simulation.Theexperiment results showed that CPS-SPWM technology has better linearity andbetter harmonic characteristics than the traditional PWM technology. At the sametime, in order to produce more even more CPS-SPWM wave in a control system, themodulation the wave generator is designed based on FPGA.Finally, the controlsystem of high voltage frequency converter is designed on the DSP chipTMS320F2812produced in TI Company, and the main program function flow chartis gived.On the base of the theoretical analysis and simulation test above, in order toverify the design of the control system can meet the actual requirements,examination of No-load and Load-carrying of control system is tested in the6KV-900KW cascaded high voltage inverter. The results show that the frequencyconverter has good output waveform and low harmonic content in lower frequency.Through test results, the above design of frequency converter is confirmed rationaland feasible.