Research And Design Of Switching Power Supply Reserved For Frequency Inverter

Modern power electronics technology as a continuously mature discipline has developed to the present,the frequency converter controls the electric equipment of the motor by changing the working frequency of the motor.The inverter is mainly composed of rectifier(AC?DC converter),filter,inverter(DC?AC),brake unit,drive unit,detection unit,micro processing unitand so on.Switching power supply as an important branch of power electronics devices,also provide energy to modern science and social life,through the control of the PWM and the switch tube on and off to stabilize the output voltage.Switching power supply for the inverter control circuit and drive circuit power supply.The performance of the switching power supply has a direct influence on the quality of the frequency converter.This paper is based on the working principle of frequency converter and the structure design of each part,a multi output flyback switching power supply is designed for the inverter power supply,the input voltage is 200VDC?750VDC,the four outputs are 24V,1A,+15V,2A,-15 V,1A,+5V,3A.This paper describes the background and significance of inverter and its performance requirements,the topological structure and working principle of switching power supply,through the analysis of choosing reasonable topology,and the hardware design of switching power supply,including the design of each part of the circuit design,device selection,transformer,design,principle diagram of the PCB plate,and then is designed the whole power supply.The application of the control chip UC3845 to switch power supply to provide a good driving ability,the control system adopts the current double closed loop,and the feedback loop is used to stabilize the output voltage,finally to provide high quality electric energy converter.After repeated experiments and repeatedly modify the design,and finally made a high performance indicators of the inverter auxiliary switching power supply prototype.The experimental results show that the switching power supply is designed with good voltage regulation performance,and the voltage ripple,load adjustment rate and the characteristics of the low voltage adjustment rate,and can provide excellent power for frequency converter.Finally,the switching power supply experiment and debugging,output waveform analysis.Finally,through the efficiency of the switching power supply,ripple size and other data to verify the performance superiority of the physical.