Detection device and method, and program

Patent metadata

Field	Value
Publication number	US-9482701-B2
Application number	US-201113989561-A
Country	US
Kind code	B2
Filing date	Mar 16, 2011
Priority date	Nov 30, 2010
Publication date	Nov 1, 2016
Grant date	Nov 1, 2016

Abstract

A detection device for detecting a state of electric power has a first current transformer that measures a first current on a first power line side of a connecting point between a first power line derived from a commercial power supply and a second power line derived from a power generation device which supplies electric power equal in frequency to the commercial power supply, a second current transformer that measures a second current on a second power line side of the connecting point, a first calculation unit that calculates a decision value based on a product of a measured value of the first current and a measured value of the second current, and a detection unit that detects a power flow direction of electric power of the first power line based on the decision value.

First claim

The invention claimed is:

1. A detection device for detecting a state of electric power, comprising:
a first current transformer that measures a first current on a first power line side of a connecting point between a first power line derived from a commercial power supply and a second power line derived from a power generation device which supplies electric power equal in frequency to the commercial power supply;
a second current transformer that measures a second current on a second power line side of the connecting point;
a first calculation unit that calculates a decision value based on a product of a measured value of the first current and a measured value of the second current; and
a detection unit that detects a power flow direction of electric power of the first power line based on the decision value.

2. The detection device as claimed in claim 1 , wherein the first calculation unit calculates, as the decision value, a cumulated value of the products during n cycles (where n is a natural number) of the electric power of the commercial power supply.

3. The detection device as claimed in claim 1 , wherein the first calculation unit calculates, as the decision value, a product of a measured value of the first current and a measured value of the second current at a point when the second current reaches a positive or negative peak.

4. The detection device as claimed in any one of claim 1 , further comprising
a second calculation unit that calculates, based on a measured value of the first current and a power flow direction of electric power of the first power line, a first electric power supplied from the commercial power supply to the first power line and a second electric power supplied from the power generation device to the first power line.

5. The detection device as claimed in claim 4 , wherein based on a measured value of the first current, a measured value of the second current and a power flow direction of electric power of the first power line, the second calculation unit further calculates a third electric power supplied to a load connected to the connecting point.

6. The detection device as claimed in claim 4 , further comprising
a display unit that displays the first electric power and the second electric power.

7. The detection device as claimed in claim 4 , further comprising
a communication unit that transmits, to outside, information including at least one combination of a combination of the first electric power and the second electric power and another combination of a measured value of the first current and a power flow direction of electric power of the first power line.

8. A detection method performed by a detection device for detecting a state of electric power, comprising:
a measurement step of measuring a first current by a first current transformer on a first power line side of a connecting point between a first power line derived from a commercial power supply and a second power line derived from a power generation device which supplies electric power equal in frequency to the commercial power supply, and measuring a second current by a second current transformer on a second power line side of the connecting point;
a calculation step of calculating a decision value based on a product of a measured value of the first current and a measured value of the second current; and
a detection step of detecting a power flow direction of electric power of the first power line based on the decision value.

9. A detection device comprising:
a calculation unit that calculates a decision value based on a product of a measured value of a first current and a measured value of a second current, where the first current is measured by a first current transformer on a first power line side of a connecting point between a first power line derived from a commercial power supply and a second power line derived from a power generation device which supplies electric power equal in frequency to the commercial power supply, and where the second current is measured by a second current transformer on a second power line side of the connecting point; and
a detection unit that detects a power flow direction of electric power of the first power line based on the decision value.

10. A detection method performed by a detection device for detecting a state of electric power, comprising:
a calculation step of calculating a decision value based on a product of a measured value of a first current and a measured value of a second current, where the first current is measured by a first current transformer on a first power line side of a connecting point between a first power line derived from a commercial power supply and a second power line derived from a power generation device which supplies electric power equal in frequency to the commercial power supply, and where the second current is measured by a second current transformer on a second power line side of the connecting point; and
a detection step of detecting a power flow direction of electric power of the first power line based on the decision value.

11. A non-transitory computer readable medium storing a program that causes a computer to perform:
a calculation step of calculating a decision value based on a product of a measured value of a first current and a measured value of a second current, where the first current is measured by a first current transformer on a first power line side of a connecting point between a first power line derived from a commercial power supply and a second power line derived from a power generation device which supplies electric power equal in frequency to the commercial power supply, and where the second current is measured by a second current transfoimer on a second power line side of the connecting point; and
a detection step of detecting a power flow direction of electric power of the first power line based on the decision value.

Assignees

• Imai Hiroshi
• Kawabata Yasuhiro
• Sameshima Hiroshi
• Misumi Shuichi
• Omron Tateisi Electronics Co

Inventors

• Imai Hiroshi
• Kawabata Yasuhiro
• Sameshima Hiroshi
• Misumi Shuichi

Classifications

• Y02B10/14

  Cross-Sectional Technologies · mapped topic

• G01R21/00 Primary

  Arrangements for measuring electric power or power factor (G01R7/12 takes precedence) · CPC title

• G01R19/2513 Primary

  Arrangements for monitoring electric power systems, e.g. power lines or loads; Logging · CPC title

• G01R21/06

  by measuring current and voltage (G01R21/08 - G01R21/133 take precedence) · CPC title

• G01R21/133

  by using digital technique · CPC title