Title:
THREE-PHASE PWM VOLTAGE GENERATING CIRCUIT
Document Type and Number:
Japanese Patent JP3447366
Kind Code:
B2
Abstract:
PURPOSE: To generate a pulse width enough to detect a current of a DC bus line in a voltage generating circuit, by controlling three kinds of vectors made up of two base voltage vectors with a give phase difference and a nullvector obtained by switching one of the base vectors.
CONSTITUTION: A command voltage vector with a desired dimension (V) 9 and phase (θ) 8 is generated when three kinds of voltage vectors made up of a nullvector and two base voltage vectors with a difference of 120° in phases. The nullvector is obtained by switching one phase of the base phases in a switching state are subjected to time-ratio control. When the phase θ 8 is 30 to 90°, the control sequence is (0, 0, 0)→(1, 0, 0)→(0, 0, 0)→(0, 1, 0)→(0, 0, 0). Then, a pulse width sufficient to detect a current of a DC bus line is generated even when an output voltage is low or a phase angel of command voltage vector is similar to the phase angle of the base voltage vector.
Inventors:
Hiroshi Mochikawa
Application Number:
JP8213594A
Publication Date:
September 16, 2003
Filing Date:
April 21, 1994
Export Citation:
Assignee:
Toshiba Corporation
International Classes:
H02M7/48; H02P27/06; H02P27/08; (IPC1-7): H02M7/48; H02P7/63
Domestic Patent References:
| JP63174589A | ||||
| JP1259761A |
Attorney, Agent or Firm:
Hideaki Togawa
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