| 摘要 |
PROBLEM TO BE SOLVED: To maintain the performance of an inverter and improve the reliability of a smoothing capacitor by providing a temperature sensor and a current sensor which detects a ripple current in the smoothing capacitor and providing a ripple current judgement device, a temperature judgement device, a deterioration service life judgement device, a temperature integration judgement device, etc. SOLUTION: While an elevator is operated, a temperature signal T of a smoothing capacitor 4 is input in a temperature judgement device 18 to compare it with a detection level T1 which is set in the temperature judgement device 18 in advance. When the temperature signal T exceeds the detection level T1 , an acceleration signal S1 is decreased depending on a degree of temperature which exceeds the detection level T1 and is output to a speed command generator 14. The speed command generator I4 outputs a speed command ωr* based on the acceleration signal S1 to suppress acceleration of a car 10 of the elevator through a speed control section 15, a PWM control device 16, an inverter section 6, and a guidance motor 7. Thus, it is possible to suppress temperature of the smoothing capacitor and prolong the service life without stopping the elevator by load reduction operation. |
