【摘要】 为解决感应电机低速和零速时的转子位置跟踪问题,提出一种电流瞬态响应二次测量结果相叠加获得转子位置的检测技术.利用逆变器产生的脉冲作为激励信号,通过瞬态电流响应得到可反映转子位置信息的寄生效应特征.讨论了逆变器馈电时瞬态激励转子位置检测的数学模型,针对脉宽调制(PWM)恒压源逆变器馈电时存在的死区效应、负面效应等负面非理想特性的影响;通过仿真手段分析了逆变器死区效应对电流瞬态响应的影响,并给出相应补偿策略;采用改进型的双模滤波器,有效地抑制了负面效应引起的共模和差模dv/dt及瞬态电流波形畸变.在3 kW感应电机试验平台上进行了验证,结果表明瞬态电流检测结果具有可反映转子位置信息的寄生效应.更多还原

【Abstract】 To track the rotor position of an induction motor at standstill and higher speeds,an approach by superposing twice subtraction of current transient samples was proposed.Voltage test pulse generated by inverter was injected into the phase windings,and the transient current changes were evaluated to obtain the parasitic effects due to rotor position.The mathematic model for an inverter-fed induction motor excited by transient pulses was discussed.According to the non-ideal behavior of dead-time effect and side-effects,which were caused by PWM inverter in sensorless control system,the simulated waves of current transient change due to exciting pulses with and without dead time were compared,and a compensation method was introduced to reduce the dead-time effect.An improved inverter side passive filter was proposed for mitigating dv/dt values of common-mode and differential-mode as well as the distortion of transient current response.The rotor position information for a 3 kW induction motor was derived by the method,and the feasibility of the proposed method was verified through experiments.The results show that the transient current has parasitic effects to reflect rotor position.更多还原