Electrical angle-detecting apparatus and driving system of synchronous
motor using the same
    3.
    发明授权
    Electrical angle-detecting apparatus and driving system of synchronous motor using the same 失效
    电动角度检测装置和同步电动机的驱动系统

    公开(公告)号:US5608300A

    公开(公告)日:1997-03-04

    申请号:US328063

    申请日:1994-10-24

    摘要: The present invention provides a system for detecting a rotational orientation or electrical angle of a rotor without any specific sensor so as to efficiently control a synchronous motor even while the rotor is at a stop or rotates at a relatively low speed. An electrical angle of a rotor (50) is determined according to a previously stored relationship between inductances of different interphases and electrical angles. At a first step, an electrical angle .phi. is calculated either in a range of 0 through .pi. or in a range of .pi. through 2.pi. by approximation. At a second step, a range where the electrical angle .phi. belongs to is specified by taking advantage of asymmetrical property of a maximum current in response to a voltage applied to each interphase. An equivocal electrical angle .theta. is then determined in a range of 0 through 2.pi.. In order to control the driving current of a three-phase synchronous motor (40) at better efficiency, a preferable system of the invention determines the electrical angle according to the above method while the rotor (50) is under inactivating condition or rotates at a speed of less than a predetermined rotating speed, and detects the electrical angle with a reverse electromotive voltage while the rotor (50) rotates at a speed of not less than the predetermined rotating speed.

    摘要翻译: 本发明提供了一种用于检测没有任何特定传感器的转子的旋转取向或电角度的系统,以便即使在转子停止或以相对低的速度旋转时也能有效地控制同步电动机。 根据先前存储的不同相间电感和电角度的关系确定转子(50)的电角度。 在第一步骤中,通过近似,在0至pi的范围内或在pi至2π的范围内计算电角度phi。 在第二步骤中,通过利用响应于施加到每个相间的电压的最大电流的不对称性来指定电角度phi所属的范围。 然后在0至2π的范围内确定不明确的电角度θ。 为了以更高的效率来控制三相同步电动机(40)的驱动电流,本发明的优选系统根据上述方法确定电角度,同时转子(50)处于失活状态或在一个 速度小于预定转速,并且当转子(50)以不小于预定旋转速度的速度旋转时,用反向电动势检测电角度。