Research On Motor Drive System Control Strategies And Overlap-time Compensation Methods Of Current-source Inverter

Compared to voltage-source inverter,the current-source inverter can produce lower total harmonic distortion in motor stators,and it provides natural shoot-through short-circuit protection capability,and it can expand the range of operation in motor drive system.Recently,because of aforementioned inherent advantages of current-source inverter,effort has been increased in the study of current-source inverter.This paper focuses on the study of the motor drive system achieved by using current-source inverter,some goals are achieved.First of all,this paper designed a multiloop controller based on the synchronous rotating reference frame and the rotor-flux oriented control strategy.To avoid the parallel resonance betwoon the ac-side filter capacitor and the stator inductance,an active damping method which is based on parallel connection virtual resistor with the ac side filter capacitor was introduced into the controller.Secondly,to achive lower dc-side current and to reduce loss,a fixed modulation index method was used in this paper.And the dc-side current was reduced further by set the rotor flux to a optimal value by the derivation of the value of rotor flux and the value of dc-side current.And this paper gave the value of choice range of the inductance in dc-side based on the value of ripple waves in the dc-side current.And this paper gave the value of choice range of the filter capacitor in ac-side based on the steady-state equivalent circuit of the ac-side.Thirdly,this paper analysed the influence of inserting overlap-time when generating PWM waves.And this paper gave the compensating method by comparing with dead-time effect and the compensating method in voltage-source inverter.Finally,this paper built a current-source motor drive control system model using MATLAB/SIMULINK,and this paper tested and verified the practicability of the raised control strategy.And this paper compred the total harmonic distortion between uncompensated when generating PWM waves and using the compensation method raised by this paper.This paper tested and verified the practicability of the raised control strategy based on the experiment platform consists of an IGBT inverter bridge and a 1.2KW asynchronous machine.