| 摘要 |
PURPOSE:To prevent the decrease of a flicker improving effect by detecting a current or reactive power of a flicker producing load in a response delay and compensating the response delay of the detection by a pulse signal synchronized with the operation of a plurality of loads. CONSTITUTION:A welding machine 1 is connected to an electric circuit and delivers a signal synchronized with an operation to a transistor 7. The delivered signal is received by a photocoupler 8, and monostable multivibrators 9a, 9b are operated. The multivibrators 9a, 9b generate pulse signals by rise pulses at the operation starting time of the load and fall pulses at the operation finishing time for the response delay time, and deliver equivalent voltages to an adder through semiconductor switches 10a, 10b. On the other hand, a load current is detected by a current transformer 2, a detector 13 detects in a response delay, and equivalent voltage is inputted to an adder 11. The signal which is processed in addition or subtraction by the adder 11 is inputted to a selector 12 to control power semiconductor switches 4a-4c without response delay, thereby preventing the decrease of flicker improving effect. |
