Research Of IPMSM Control System Based On Maximum Torque Per Ampere

Sustainable development of modern society has more efficient requirements of energy, the government is vigorously promoting energy conservation and has issued related policies. Motor takes a large proportion of electricity consumption. The improvement of motor efficiency has important value on research and application especially in the industrial and the vehicle industry. Built-in permanent magnet synchronous motors has many advantages such as power density and torque density. Sundry control strategies of IPMSM has been developed for different performance requirement. IPMSM has asymmetric magnetic circuit in structure because of the different permanent magnet excitation and placement form. When the current of direct axis is not zero, IPMSM can produce reluctance torque. The MTPA control strategy which is to achieving full use of reluctance torque to maximize torque current ratio can minimize copper loss, and then it will improve torque output capacity and energy efficiency. The main work of maximum torque control system based IPMSM current ratio is as follows:1. Analyzed and designed SVPWM generation using space voltage vector length and angle which include the calculation of inserting both end and middle symmetry zero vector, and inserting dead time. Analyzed dead effect and compensation strategies. The designed method is easy to limit the space voltage vector length, to reduce the trigonometric calculation and to avoid jitter caused by out of step or more step.2. Analyzed the innate character of maximizing reluctance torque. Analyzed the fundamental of MTPA control strategies which use calculation formula and auxiliary signal injection method. The expectation function was derived from the voltage and torque equation in the IPMSM mathematical model. Designed the MTPA control strategy using the derived expectation function based on vector control principle.3. Analyzed the effect to the MTPA status by the changed parameters caused by magnetic saturation. Adjust parameters online through curve fitting to improve the robustness.4. Design the hardware and software of IPMSM control system. Build the simulation model of control strategy. Analyzed the designed control strategy and contrast the data of simulation and theoretical value and test result.Research completed the control system design and product. It was proved that the designed MTPA control strategy is effectiveness and stability through simulation and experiment.