Protection and control system, protection and control device, and merging unit

Patent metadata

Field	Value
Publication number	US-9450400-B2
Application number	US-201414260996-A
Country	US
Kind code	B2
Filing date	Apr 24, 2014
Priority date	Nov 11, 2011
Publication date	Sep 20, 2016
Grant date	Sep 20, 2016

Abstract

A protection and control system includes a first merging unit which obtains an electric variable from a transformer, and digitally converts the obtained electric variable to output the converted electric variable as first electric variable information to a first network, a plurality of first protection and control devices, each of which obtains the first electric variable information from the first merging unit through the first network, judges whether or not a system fault occurs, and outputs main trip information to the first network when that the system fault occurs is judged, and a second protection and control device which obtains the first electric variable information from the first merging unit through the first network, judges whether or not the system fault occurs in the zone to be protected of the electric power system.

First claim

What is claimed is:

1. A protection and control system, comprising:
a first merging unit which obtains an electric variable from a transformer installed in an electric power system, and digitally converts the obtained electric variable to output the converted electric variable as first electric variable information to a first network;
a plurality of first protection and control devices, each of which obtains the first electric variable information from the first merging unit through the first network, judges whether or not a system fault occurs in a zone to be protected of the electric power system based on a predetermined relay characteristic, and outputs main trip information to the first network when that the system fault occurs is judged; and
a second protection and control device which obtains the first electric variable information from the first merging unit through the first network, judges whether or not the system fault occurs in the zone to be protected of the electric power system based on a plurality of the relay characteristics which are predetermined as respective fault detection relays of the first protection and control devices, and outputs Fault Detector trip information to the first network when that the system fault occurs is judged,
wherein the first merging unit judges opening or closing of a circuit breaker or a switch which is installed in the electric power system based on the main trip information and the FD trip information.

2. A protection and control system, comprising:
a first merging unit which obtains an electric variable from a transformer installed in an electric power system, and digitally converts the obtained electric variable to output as first electric variable information to a first network;
a second merging unit which obtains the electric variable from the transformer installed in the electric power system, and digitally converts the obtained electric variable to output as second electric variable information to a second network;
a first protection and control device which obtains the first electric variable information from the first merging unit through the first network, judges whether or not a system fault occurs in a zone to be protected of the electric power system based on a predetermined relay characteristic, and outputs a main trip information to the first network when that the system fault occurs is judged; and
a second protection and control device which obtains the second electric variable information from the second merging unit through the second network, judges whether or not the system fault occurs in the zone to be protected of the electric power system based on a plurality of the relay characteristics which are predetermined as respective fault detection relays of the first protection and control devices, and outputs Fault Detector trip information to the first network when that the system fault occurs is judged,
wherein the first merging unit judges opening or closing of a circuit breaker or a switch which is installed in the electric power system based on the main trip information and the FD trip information.

3. A protection and control system, comprising:
a first merging unit which obtains an electric variable from a transformer installed in an electric power system, and digitally converts the obtained electric variable to output the converted electric variable as first electric variable information to a first network;
a second merging unit which obtains the electric variable from the transformer installed in the electric power system, and digitally converts the obtained electric variable to output as second electric variable information which is different from the first electric variable information to a second network;
a plurality of first protection and control devices, each of which obtains the first electric variable information from the first merging unit through the first network, judges whether or not a system fault occurs in a zone to be protected of the electric power system based on a predetermined relay characteristic, and outputs a main trip information to the first network when that the system fault occurs is judged;
a second protection and control device which obtains the second electric variable information from the second merging unit through the second network, judges whether or not the system fault occurs in the zone to be protected of the electric power system based on a plurality of relay characteristics which are predetermined as respective fault detection relays of the first protection and control devices, and outputs Fault Detector trip information to the second network when that the system fault occurs is judged; and
a cable to connect the first merging unit and the second merging unit,
wherein the first merging unit judges opening or closing of a circuit breaker or a switch which is installed in the electric power system based on the main trip information outputted from the first protection and control devices and the FD trip information outputted from the second protection and control device through the cable.

4. The protection and control system according to claims 1 , wherein:
the first merging unit obtains the main trip information and the FD trip information, and judges to open the circuit breaker or the switch in case that the FD trip information is outputted based on the relay characteristic corresponding to the fault detection relay of the main trip information.

5. A protection and control device, comprising:
a transmission processing unit which receives, from a merging unit which obtains an electric variable from a transformer installed in an electric power system, and digitally converts the obtained electric variable to output as electric variable information, the electric variable information through a network; and
a relay calculating unit which judges whether or not a system fault occurs in a zone to be protected of the electric power system based on the electric variable information obtained from the transmission processing unit and a plurality of relay characteristics which are predetermined as respective fault detection relays of a plurality of first protection and control devices each having a specific relay characteristic, and outputs Fault Detector trip information to the transmission processing unit when that the system fault occurs is judged,
wherein the transmission processing unit outputs the FD trip information obtained from the relay calculating unit to the network.

6. A protection and control device, comprising:
a first transmission processing unit which receives, from a merging unit which obtains an electric variable from a transformer installed in an electric power system, and digitally converts the obtained electric variable to output as electric variable information, the electric variable information through a first network;
a relay calculating unit which judges whether or not a system fault occurs in a zone to be protected of the electric power system based on the electric variable information and a predetermined relay characteristic, and outputs Fault Detector trip information when that the system fault occurs is judged; and
a second transmission processing unit which outputs the FD trip information obtained from the relay calculating unit to a second network,
wherein the relay calculating unit judges based on a plurality of the relay characteristics which are predetermined as respective fault detection relays of a plurality of protection and control devices connected to the first network or the second network.

7. A merging unit, comprising:
an input converter which obtains an electric variable detected by a transformer installed in an electric power system;
an A/D converter which digitally converts the electric variable obtained by the input co

Assignees

• Toshiba Kk

Inventors

• Ohtomo Yu
• Ishibashi Akira

Classifications

• H02H3/08

  responsive to excess current (responsive to abnormal temperature caused by excess current H02H5/04) · CPC title

• H02H3/05

  with means for increasing reliability, e.g. redundancy arrangements {(for logic circuits H03K19/003)} · CPC title

• Y04S10/16

  Electric power substations · CPC title

• Y02E60/723

  Cross-Sectional Technologies · mapped topic

• H02J13/0062

  Electricity · mapped topic