| 摘要 |
PURPOSE:To enable to accurately follow up to the line by using the power source frequency of a master motor as a master side speed signal, thereby eliminating the expensive measuring means. CONSTITUTION:A timing signal of zero degree phase angle is detected by a phase detector 5 from the phase current of a master side motor 1, and this timing signal is inputted as the speed signal of the motor 1 to microcomputers of inverters 41-4n. The microcomputers respectively receive as interrupt signal to a CPU timing signals, and count the interval of the timing signals by the synchronous pulse of contained clock oscillator by the start of the interrupt process to produce the variation in the speed of the motor 1, thereby controlling the inverter. Thus, the operating speeds of the slave side motors 31-3n are controlled at the same speed ratio as the speed of the master side motor 1. |
