发明名称 |
Method and apparatus for controlling PWM inverters |
摘要 |
An AC motor such as an induction motor or a synchronous motor is driven by a PWM inverter circuit. Power switching elements of the inverter circuit are ignited by PWM pulses resulting from comparison of a carrier wave signal with a sine wave modulation signal at a frequency proportional to a frequency setting signal so as to control the inverter circuit. A current polarity detector detects positive and negative components of a DC current flowing in the input side of the inverter circuit. The frequency setting signal is so corrected as to be decreased when only the positive current component flows in excess of one period of the carrier wave signal or increased when only the negative current component flows in excess of the one period.
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申请公布号 |
US4599549(A) |
申请公布日期 |
1986.07.08 |
申请号 |
US19850723646 |
申请日期 |
1985.04.16 |
申请人 |
HITACHI, LTD. |
发明人 |
MUTOH, NOBUYOSHI;SAKAI, KEIJIRO;UEDA, AKITERU;ISHIBASHI, AKIRA;OKAJIMA, IKUO |
分类号 |
H02M7/5387;H02P23/04;H02P25/02;H02P27/08;(IPC1-7):H02P5/40 |
主分类号 |
H02M7/5387 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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