Title:
単独運転検出装置
Document Type and Number:
Japanese Patent JP5505145
Kind Code:
B2
Abstract:
With a method whereby reactive power is changed from a fluctuating output to a constant output by a frequency rise or fall monitor circuit stage level being exceeded, and an isolated operation is detected, a problem occurs with a small scale grid in that, as the frequency is liable to fluctuate due to a load fluctuation, there is liable to be a false detection of an isolated operation. In contrast, an abnormal frequency stage detection can be performed such that the frequency at a point when the rising edge of a reactive power fluctuation is detected, and the frequency at a point when the falling edge is detected, are detected sequentially, and an abnormal frequency stage detection is recognized when the order of the difference between the current detection value and the previous detection value is “increase”, “decrease”, “increase”.
Inventors:
Yamada Toshiya
Mikisuke Fujii
Mikisuke Fujii
Application Number:
JP2010156348A
Publication Date:
May 28, 2014
Filing Date:
July 09, 2010
Export Citation:
Assignee:
Fuji Electric Co., Ltd.
International Classes:
H02J3/38
Domestic Patent References:
| JP8331765A | ||||
| JP10257678A | ||||
| JP2010038826A | ||||
| JP3256533A |
Attorney, Agent or Firm:
Yoichi Matsumoto