(EN)
This invention provides a simple method of stopping pump drives smoothly without chattering occuring. It is achieved by using an a.c. controller to increase the operating angle (D) between the motor current and voltage from zero in accordance with linear function, the phase angle (PA) decreasing until it reaches a turning point (w). When observation of the phase angle (PA) indicates that the turning point (w) has been reached, the phase is controlled, from this point on, by means of a control unit in accordance with a linear reference curve of phase angle versus time (R(t)). The motor rpm does not change abruptly since a rapid change in phase angle is avoided.
(ZH) 本发明为一简单的使泵驱动装置平滑停机的方法,同时可避免压力冲击波。为此借助一交变电流调节器使电机电流和电压间的移相角(D)从零度始按一直线斜坡增加,相位角(PA)下降并达到一转折点(W)。如果根据对相位角的观察该转折点(W)被检测到,则由此时起借助一调节器依预定的随时间线性变化的相位角额定值曲线(R(t))实施移相控制。依此电机转数不再突然地变化,因为快速相位角变化已被避免了。