Title:
CONTROL SYSTEM OF INDUCTION MOTOR BY PULSE WIDTH MODULATION INVERTER
Document Type and Number:
Japanese Patent JPS5833998
Kind Code:
A
Abstract:
PURPOSE:To suppress the variation in the torque of an induction motor by providing means for adjusting a reference value for sequentially switching the number of pulses contained in the half cycle of the output voltage of an inverter in response to the DC power source voltage inputted to the inverter. CONSTITUTION:The rotating frequency and instructed frequency value of an induction motor 3 are calculated by an adding and subtracting circuit 11, and a switching element of an inverter 2 is operated On or OFF through a modulator which includes a sinusoidal wave generator 52 and a triangular wave generator 51 controlled at the peak value in response to the deviation of the input current of the motor 3. In this case, the voltage of the power source 1 is detected by a detector 13, is inputted together with the current instructed value to a pulse number switching circuit 12, and the output frequency of the inverter 2 is variably set by controlling the generator 51. Accordingly, the variation in the torque when the number of pulses is switched can be suppressed, thereby preventing the production of the commutation failure of the inverter.
Inventors:
TANAMACHI TOKUNOSUKE
NARITA HIROSHI
IBAMOTO MASAHIKO
OKAMATSU SHIGETOSHI
NARITA HIROSHI
IBAMOTO MASAHIKO
OKAMATSU SHIGETOSHI
Application Number:
JP13174081A
Publication Date:
February 28, 1983
Filing Date:
August 21, 1981
Export Citation:
Assignee:
HITACHI LTD
International Classes:
H02P27/08; H02M7/527; (IPC1-7): H02P7/62
Domestic Patent References:
| JPS51136131A | 1976-11-25 | |||
| JPS5612865A | 1981-02-07 |
Attorney, Agent or Firm:
Katsuo Ogawa