Research On Permanent Magnet Synchronous Motor Speed ??Regulation System Based On Maximum Torque Current Ratio

At present,our country is in the middle stage of industrialization construction.In the future development,energy consumption will further increase.Fans and pumps are widely used in industrial production,with the characteristics of large application and wide application,and the power consumption of their supporting motors is also very large.Fans and pumps in industrial production generally run inefficiently during the actual production process.Therefore,it is necessary to increase the efficiency of the motor for fan and water pump.Compared to traditional asynchronous motors,salient pole permanent magnet synchronous motors have high efficiency,simple structure,and small size.The asymmetry of the rotor magnetic circuit structure can generate reluctance torque.In the permanent magnet synchronous speed control system,the maximum torque current ratio(MTPA,Maximum Torque per Ampere)control strategy can make full use of the reluctance torque,thereby improving the motor's torque output capability and system efficiency.Therefore,in this paper,the supporting motor of the fan and pump motor uses a salient pole PMSM,and the MTPA control strategy of the salient pole permanent magnet synchronous motor is studied.This paper studies the two methods of realizing the maximum torque-current ratio,which are the formula calculation method and the high-frequency signal injection method.According to the definition of MTPA control strategy,the reference value of the AC and DC axis current is derived,and the formula is simplified by equivalent parameter transformation to achieve MTPA control.The formula method is affected by the changes of the motor parameters and can only improve the motor efficiency to a certain extent.The advantage of the high-frequency signal injection method is that it is more robust and insensitive to changes in motor parameters.The current vector angle of the MTPA control strategy can be obtained by processing the instantaneous input power.The MATLAB/Simulink simulation platform is used to simulate and analyze the researched control strategy to verify the correctness of the theoretical analysis.This paper implements the MTPA control algorithm in the control system with DSP as the core control chip,builds a 65 kW salient pole permanent magnet synchronous motor speed control system experimental platform,and conducts experiments on the platform to further prove the MTPA control strategy studied feasibility.