| 摘要 |
PURPOSE:To attempt the reduction of voltage distortion generating by high frequency current when plural motors operating through thyristor converters are changedover to an emergency powder source by a method wherein condensive capacitors of suspending motors are connected to a motor to be operated. CONSTITUTION:Motors 4A-4C for elevators, etc., are operated by an a.c. source 1 through thyristor converters 5A-5C, and are changed-over to an energency generator 2 when the service interruption took place. When the changeover is to be performed, a contact 3f is closed and an electromagnetic contactor 6A is closed by a selective switch 12 to operate only the motor 4A, electromagnetic contactors 8A-8C hold the closing state and condensive capacitors 10B, 10C of the suspending motors 4B, 4C are connected to the motor 4A in that condition. Therefore a high frequency current generating from the thyristor converter 5A can be led into the capacitor having a large capacity to reduce the voltage distortion and to prevent a harmful influence against other loads 11. |
