捷联式自动垂直钻井系统用逆变器脉宽调制方法优化

Research on Pulse Width Modulation Method Optimization of Inverter Used in Strap-Automatic Vertical Drilling System

捷联式自动垂直钻井系统是一种能够有效解决"防斜打快"这一钻井技术难题的机电液集成钻井装置,永磁同步电机控制系统是其实现电控液压导向功能的重要组成部分。针对井下高温环境中永磁同步电机控制系统供电电压宽范围变化时,逆变器损耗与窄脉冲抑制问题,本文提出了一种开关频率在线调整的最大脉宽矢量调制方法(MPW-SVM),将6个60°大扇区细分为12个30°小扇区,实现最大脉宽调制的零矢量最优分配,能够在极端电压时有效避免窄脉冲且又能够抑制开关损耗。同时,根据调制度的变化采用模糊逻辑规则实现开关频率的在线调整,从而兼顾正常电压时电流纹波的抑制。实验结果表明了该方法的有效性。

Strap-Automatic vertical drilling system is a kind of integrated drilling device centralizing the mechanical electrical,and hydraulic areas that can effectively solve the technical problem of deviation control and fast drilling.Permanent magnet synchronous motor(PMSM) control system is its significant part to achieve the electronically controlled hydraulic-driven rotary steering feature.To suppress the inverter loss and narrow pulse-width which often occur when the supply voltage of PMSM control system changes in wide range with high-temperature environment of the underground,a maximum pulse width space vector modulation(MPW-SVM) method of switching frequency adjusting on-line is proposed in this paper.Six 60 degree sectors are subdivided into twelve small 30 degree sectors to realize the optimal distribution of zero vectors for effectively suppress the switching loss and narrow pulse-width when the power supply operates at the maximum range.Meanwhile,several fuzzy logic rules are applied varying from the modulations to fulfill the function of on-line adjusting of switching frequency,and furthermore to suppress the current ripple during the normal voltage.The proposed method is verified by the experimental results.