| 摘要 |
PURPOSE:To eliminate useless consumption of electric power at an inverter by a method wherein consumption of regenerated electric power is performed every prescribed period for time duration being proportional to the regenerated electric power. CONSTITUTION:The voltage fed from a commercial electric power source 1 is applied to the input side of a converter 2, while a signal VR sent from a setting device 10 is applied to a control circuit 9, and output having voltage and frequency corresponding to the signal VR thereof is supplied to a motor 6 for load from the inverter 5. When the motor 6 is changed from power running condition over what is called regenerative running condition to apply electric power from the motor 6 to the inverter 5 conforming to regulation of the setting device 10 intending to perform retardation control of the motor 6, for example, a transistor 8 conducts every prescribed period for time duration being proportional to the regenerated electric power, and regenerated electric power is consumed by a resistor 7 only during the period thereof. |
