Title:
LOAD ESTIMATING METHOD
Document Type and Number:
Japanese Patent JP3933316
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To prevent erroneous recognition, when attention is paid to a current balance of load and estimate with higher accuracy that a connected load is a three-phase induction motor without being effected by the changed voltage balance.
SOLUTION: When a three-phase load 10 is connected to a three-phase three- wire type power distribution line, a personal computer calculates the ratio &verbar Z1/Z2&verbar of the positive phase/reverse phase impedance of a load. When such a ratio satisfies the estimated condition (10≥&verbar Z1/Z2&verbar ≥4), it is estimated that the load 10 is a three-phase induction motor. Moreover, it is an additional estimation condition that the ratio &verbar Z1/Z2&verbar not change for the specified period.
Inventors:
Motohashi Jun
Yamashina Minoru
Naoki Ishii
Naito
Yamashina Minoru
Naoki Ishii
Naito
Application Number:
JP23306798A
Publication Date:
June 20, 2007
Filing Date:
August 19, 1998
Export Citation:
Assignee:
THE TOKYO ELECTRIC POWER COMPANY,INCORPORATED
Fuji Electric Holdings Co., Ltd.
Fuji Electric Holdings Co., Ltd.
International Classes:
H02J3/00; (IPC1-7): H02J3/00
Domestic Patent References:
| JP4058797A |
Other References:
権藤豊美,不平衡負荷の最近の動向と設備上の留意点,電気雑誌 OHM,日本,1977年,VOL.64,NO.1,p.37-41
Attorney, Agent or Firm:
Yuichi Morita
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