Application Of Permanent Magnet Synchronous Motor Based On Switched Boost Inverter

This thesis is mainly applying the switched boost inverter for permanent magnet synchronous motor(PMSM)drive system,adding a boost circuit in front of the inverter circuit to form a switched boost inverter circuit.It improves motor drive performance and reduces switching losses by using discontinuous pulse width modulation(DPWM)techniques to realize the reliable.Predictive current control is applied to the permanent magnet synchronous motor which makes the system have better dynamic performance to attain universal and low distortion of the PMSM drive system.The switched boost inverter circuit mainly includes a DC/DC converter increasing a DC power supply voltage between a DC power source and an inverter,and a DC/AC inverter converting DC power into AC power.The switched boost inverter allows the DC/AC inverter circuit to operate in a through-state to avoid dead zones.It reduces the impact of output waveform on the motor and allows boost and contains only one LC network.Closed-loop control of the boosted bus voltage can filter out the AC component and effectively prevent grid voltage fluctuations from harming the bus voltage.The DPWM used in this thesis is a modulation technique that reduces the switching losses.The DPWM algorithm has only one zero vector action in one switching cycle,so the switch on each phase bridge arm does not operate in the interval of(2?)/3,it only has 8 switching actions thereby reduces about 1/3 switching loss.The DPWM technology has simple timing and software easier to implement.For the permanent magnet synchronous motor,the predictive current control(PCC)method is used to control the motor.The PCC technology can predict the future state of the system according to the current state and mathematical model of the system in a desired time.Then according to the expected value perform online optimization.At the same time,the cost function is added to make the control process reach the desired standard,and guarantees the global optimum of the selected voltage vector to improve the dynamic performance of the system,reduce the current and torque ripple.In this thesis,the basic working principle of the switched boost circuit,the inverter modulation technology and PMSM control method are studied detailedly.Then,the state analysis of the switched boost inverter,the advantages of the DPWM strategy and derivation of the PCC algorithm are discussed.The simulation model analysis was used by MATLAB/Simulink and the hardware experiment platform was built,which verifies the superiority and feasibility of the PMSM system based on the switched boost inverter.