Hardware Design And Realization Of Programmable Three-phase Linear Power Supply

With the rapid development of electrification,the power quality of the power grid is increasingly restricting the development of high-end manufacturing,such as chip manufacturing,precision motor control,special material production and processing,and frequently lead to electricity accidents.Manufacturers have turned to use standalone power to provide pure power for their equipment.This paper studies the programmable three-phase linear power supply is to meet the needs of the market and the development of high-power ultra-stable linear power supply.Its technical indicators have been close to the level of similar foreign high-end products.It's not only as a power supply can be used as precision equipment and laboratory testing and high-end power,and breaking the foreign monopoly on China's long-term supply of high-end products.Firstly,this paper studies the current situation and related products at home and abroad,and then designs the overall plan of the project and fully demonstrates its feasibility.Power amplifier using modular design,each phase output using three power amplifier in series file output,make full use of the main control chip OMAP-L138 audio interface,the use of audio fiber for data isolation transmission,and supporting the use of audio DAC production of analog signals and ADC pairs the output signal to feedback and sampling.Finally,through the isolation of RS485 as a control bus,make the various modules of the system orderly and stable work.Then,taking into account the design of the low distortion high voltage slew rate power amplifier circuit is the difficulty of this project.In this paper,combined with a variety of amplifier structure and project requirements,put forward a fully symmetrical class-B amplifier circuit structure as the final program.Then,according to the detailed analysis of the amplifier design to explain how to start from the most basic form of the circuit,and gradually improve the design of the input stage,transconductance stage,output stage and protection stage circuit,and gives the final complete amplifier circuit.Finally,the gain,distortion,output impedance,slew rate,rise time and fall time of the amplifier are analyzed and simulated,and the design of the amplifier power supply is briefly introduced.It is important to sample the output signal to form the system closed loop to the stability of the device.In this paper,the design of the higher requirement of the voltage sampling and conditioning circuit is analyzed in detail,and the detailed noise analysis and simulation are carried out.Finally,the performance of the circuit is verified by the test of the actual circuit.Finally,the key technical indicators such as the rise time,the fall time,the output offset voltage and the harmonic distortion are measured in the power amplifier module and the prototype.According to the measurement results and analysis,we can see that the key technical indicators of amplifiers and prototypes meet the requirements.