Title:
INDUCTION MACHINE VARIABLE SPEED DRIVE
Document Type and Number:
Japanese Patent JP3687331
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide an induction machine variable speed drive, which allows the calculated values of number of revolutions to be obtained at a highly frequency and is capable of being so controlled as to cope with the abrupt changes in number of revolutions.
SOLUTION: This induction machine variable speed drive comprises an inverter 1, an induction machine 2 driven by the inverter 1, a vector control means which exercises vector control relative to the direction of a primary magnetic flux command vector, a current detector 3 which detects the primary current of the induction machine, a detected current vector rotating means 5 which resolves the detected current into a d-axis component which is parallel with the primary magnetic flux command vector and a q-axis component orthogonal thereto, and a rotational speed calculating means 21, which calculates the rotational speed of the induction machine based on the d-axis component and q-axis component of the detected current for use in the vector control. The current detector 3 is capable of detecting the currents of the induction machine at high frequency, and thus obtains the results of the calculation of the rotational speed with higher frequency than in the rotational speed calculation by counting pulse signals.
Inventors:
Yasushi Matsumoto
Application Number:
JP6533798A
Publication Date:
August 24, 2005
Filing Date:
March 16, 1998
Export Citation:
Assignee:
Fuji Electric Systems Co., Ltd.
International Classes:
H02P5/74; H02P5/56; H02P21/00; H02P21/18; H02P21/24; H02P23/07; H02P23/16; H02P27/04; (IPC1-7): H02P21/00; H02P7/74
Domestic Patent References:
| JP9271200A | ||||
| JP7303399A | ||||
| JP6178593A | ||||
| JP4312382A |
Attorney, Agent or Firm:
Yuichi Morita