Novel dead-zone compensation method and system based on pulse optimization

Abstract

The invention discloses a novel dead-zone compensation method and device based on pulse optimization, used for effectively solving the problems of output voltage and current distortion and zero current clamping due to the dead-zone effect of a three-phase voltage inverter. The novel dead-zone compensation method and device based on pulse optimization are characterized in that the current polarity is judged more conveniently by utilization of a current space vector in a two-phase static coordinate system; in a three-phase current detection process, a novel filter is designed; the fact that a current harmonic component is removed by filtration can be ensured; furthermore, the phase deviation cannot be generated; the current polarity judgement precision is improved; and error compensation is avoided. The novel dead-zone compensation method disclosed by the invention is simple and effectively; current distortion due to the dead-zone effect can be effectively reduced; furthermore, the zero current clamping phenomenon is improved; the system operation performance is improved; the structure is reliable; implementation is easy; the poor dynamic stability due to driving of an electric automobile can be solved; and the acceleration performance of the electric automobile can be improved.

Description

technical field [0001] The invention relates to an electric vehicle control method and device, in particular to a dead zone compensation method and device for an electric vehicle inverter. Background technique [0002] As a key component of the AC drive system of an electric vehicle, the performance of the inverter directly affects the stability of the vehicle. Ideally, the switching signals of the upper and lower power switching devices in the same bridge arm of the three-phase voltage type inverter are complementary, but due to the turn-on and turn-off delays of the actual power switching devices, in order to prevent the upper and lower bridge arms from being passed through, usually in the switch A dead time is added during the action. The existence of the dead zone causes an error between the actual output voltage of the inverter and the target voltage, resulting in distortion of the phase voltage and phase current of the motor, zero current clamping, torque and speed pu...

AI Technical Summary

Problems solved by technology

Among them, the former is easy to implement, but the compensation is not accurate enough; the latter can accurately compensate the dead time, but has higher requirements on the control chip, requiring the controller to be able to sample twice in one carrier cycle

In addition, the detection of current polarity in the dead zone compensation method is very important, and inaccurate judgment of the current zero crossing point may lead to false compensation

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