Research on Light-Load Oscillation Suppression Strategies of Variable Frequency Inverter-Driven Induction Motors
|School||Harbin Institute of Technology|
|Course||Motor and electrical|
|Keywords||Induction motor Constant ratio control Stator voltage orientation Deadband compensation Oscillation suppression|
V / F control mode of induction motor variable frequency drive system has a simple control, better speed performance and lower cost advantages , has been widely applied in the field of AC variable speed . But following the traditional induction motor V / F variable frequency drive system at the fundamental frequency in the band -load or light load running , there are the stator current oscillation speed, torque buffeting oscillation , resulting in performance degradation of the system control and safe operation of motor had a negative impact . In order to solve the above problems , this paper conducted in-depth research system oscillation mechanism and suppression strategy . First, in the analysis based on the mathematical model of induction motors steady-state two-phase rotating coordinate system of the V / F control method of the basic principles and dq equivalent circuit of the induction motor based on the ideal V / F control mode induction motor in the space stability problems when the load operation , obtained by numerical simulation of motor parameters on the stability of the system affect the trend . Secondly, the PWM signal dead zone affect the system oscillation mechanism . Oscillation suppression method based on the duty cycle deadband compensation and its inhibitory effect is simulated and analyzed . Simulation results show that the dead-time compensation strategy can effectively solve the relatively large dead time / carrier frequency motor current oscillation and distortion problems caused by the dead zone . Again , in order to more effectively address the issue of system oscillations from a balanced point of view of the theory of instantaneous power system oscillation problems analysis, oscillatory component based on the active current feedback deadband compensation oscillation suppression strategy . MATLAB / Simulink environment to build a simulation model of the system , the system oscillation suppression program simulation study , the results show that the scheme effective solution to the oscillation problem of the system . Finally , to build a general-purpose inverters experimental platform, based on the V / F control mode was investigated experimentally . Experimental results show that proposed in this paper based on the active current feedback deadband compensation oscillation suppression strategy can be a good solution to the oscillation problem of the induction motor , effectively improve the traditional V / F control induction motor variable frequency drive system stability .