精确的初始位置估计是开关磁阻电机无反转起动的前提,是无位置传感器技术研究的一个重要方向。针对静止和惯性运行状态提出了一种基于电感综合矢量的初始位置估计方法。该方法通过在各相同时注入高频低压脉冲,利用电流斜率差值计算法来实现各相电感估计;将各相电感视为互差120电角度的电感矢量,采用旋转坐标变换和单位规范化方法很大程度上消除了高次谐波,使得变换后的三相电感可以近似由单位正弦来表示;根据坐标变换的基本理论,利用综合矢量法可以估计出转子位置信息。基于一台12/8结构样机进行了实验,验证了算法的可行性。
Accurate initial rotor position estimation is an important premise for no-reversal starting. It is also an important research branch in sensorless techniques for switched reluctance motor (SRM). In this paper, an inductance synthetic vector based initial rotor position estimation method was presented for standstill and inertial operation. By injecting high frequency low voltage pulses in each phase, the phase inductance can be estimated using phase current slope difference method. The three phase inductance can be considered as vectors with 120~ phase difference. Using the rotational coordinate transformation method and unit standardization, the high order harmonics can be eliminated to some extent, and then the inductance after coordinate transformation can be presented by a unit sine function. According to the basic principle of the coordinate transformation, the rotor position can be estimated by the synthetic vector method. The experiments have been done on a 12/8 structure SRM prototype, which verify the validity of the proposed method.