| High-power ozone power is an important power electronic equipment in the industrial application,generally the existing main circuit of ozone power adopts uncontrolled rectifier and bridge type inverter.The input current distortion will increase with the improvement of the discharge power,which further reduces the input power factor and have a serious harmonic pollution on power grid.Therefore,high-power ozone equipments need to restain current harmonic with the power factor correction technology which could improve the power factor of ozone power.This paper adds staggered parallel Boost PFC circuit between uncontrolled rectifier and dc bus on bridge type inverter to research and design a new ozone power supply with high power factor.The main circuit in power supply is composed of single phase uncontrolled rectifier,staggered parallel Boost PFC circuit,single phase bridge inverter,high frequency step-up transformer and the ozone generator tube load of series inductance compensation.Paper in the second chapter focuses on the working principle of ozone power supply,including the modal analysises about the working circuit and characteristics of electric regulation.In the third chapter it mainly analysises the three working modes of the Boost power factor correction circuit and current controlling methods under continuous conduction mode,and introduces the working principle of staggered parallel Boost PFC in detail.On the basis of the above theoretical researchs,the paper designs a 3kw ozone generator power supply with high power factor and analyzes the experimental results of sample machines in detail.In this paper,design of power factor correction circuit adopts TI UCC28070 simulation control chip,the CCM mode of average current control method is adopted to realize the track of current waveform to voltage waveform and make both of them in the same phase,using the voltage loop control to ensure the stability of the output voltage,the double closed-loop control of current loop and voltage loop can achieve active power factor correction in ozone power supply.Ozone power main circuit adopts the DBD type series resonance topology,the waveform after power factor correction feeds into rectifying circuit and the obtained dc signal is inverted to high frequency square wave signal under the action of IPM module,then the signal disposed by the high frequency boost converter is sent to the ozone generating tube to produce ozone.TI processor TMS320F28070 is used in the power controller,and the control strategy is phase shift PWM +PDM,by changing the phase-shifting angle and the density of PDM to realize the adjustment of ozone power supply,the load current frequency tracking and phase compensation are used to make the ozone generator work in quasi resonant state,which improve the discharge efficiency of ozone.The experimental results verify the feasibility of design scheme in this paper. |
