JP2001197658A - Load selection/cut-off system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly reliable load selection/cut-off system which can be structured easily. SOLUTION: Data exchange is conducted by connecting the load selection/ cut-off units 101, 102, etc., discretely allocated for every load breaker and calculation of cut-off load and selection of preset output are also conducted for each load selection/cut-off unit 101, 102, etc., using the common data such as the priority of load selection/cut-off preset with a handy terminal 40, amount of power to be supplied with a power generator, a load power fetched in each load cut-off unit 101, 102, etc., and condition of the breaker or the like. Thereby, a load selection/cut-off system can be realized, which may be structured easily and assures higher reliability, in comparison with the existing system which uses a controller for arithmetic operations.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a selective shutoff system used in a power receiving and transforming facility connected to a generator.

[0002]

2. Description of the Related Art A load selective cutoff system is provided for preventing an overload of a generator when a power failure or the like occurs in a commercial power supply in a substation facility connected to the generator.

[0003] Although the frequency of actual operation of this system is low,
If load shedding fails, the generator will stop due to overload,
There will be a total power outage. For this reason, high reliability is required for this system.

FIG. 5 shows the configuration of a conventional load selection / interruption system.
Shown in In the figure, reference numeral 51 denotes a man-machine interface for setting the cutoff priority of the cutoff load and the power that can be supplied by the generator, and 52 denotes a controller for arithmetic processing. 53 ₁ , 53 ₂ ,... Are circuit breaker control circuits for the breaking load (# 1), the breaking load (# 2),. , Preset output means and the like. Reference numeral 54 denotes a remote station, which is an analog input board 54 for receiving signals from the power converters of the respective breaker control circuits 53 ₁ , 53 ₂ ,.
a, a digital input board 54b for receiving a signal from the circuit breaker input means, a relay output board 54c for outputting a signal to the preset output means, and these respective boards 54a, 54
b, 54c for input / output processing of signals input and output from the controller 52, and transmission processing for controlling and processing transmission of signals transmitted and received between the input / output processing means 54d and the controller 52 via the transmission line 55. And means 54e.

In this conventional load selection and interruption system, a dedicated controller 52 is provided for arithmetic processing, and inputs from the circuit breaker side, that is, each circuit breaker control circuit 53 ₁ , 53 ₂ ,. The conditions of the set values (shutdown priority, generator suppliable power) set in step (1) are processed, and the results are output to the breaker control circuit side as selective cutoff presets.

For this reason, the controller 5 for arithmetic processing
2. Input to each circuit breaker control circuit 53 ₁ , 53 ₂ ,.
A remote station 54 serving as an output device, and a cable connecting the controller 52, the remote station 54, and each of the circuit breaker control circuits 53 ₁ , 53 ₂ ,.

[0007]

As described above, in the conventional load selection and cutoff system, it is necessary to provide a dedicated arithmetic processing controller 52 and a remote station 54 as an input / output device.

Further, when the controller 52 for arithmetic processing or the remote station 54 serving as an input / output device fails, all the functions of load selection and cutoff have been stopped.

[0009] Then, it is necessary to create an arithmetic processing program for each facility to which the program is applied.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a highly reliable load selection and cutoff system that can be easily constructed.

[0011]

A load selection / interruption system according to the present invention is provided with setting means for setting an interruption priority of each load and suppliable power, and is provided for each load, and is provided between other loads. Transmission processing means for transmitting and receiving information on the power and circuit breaker state of each load, and information on the power and circuit breaker state of each load transmitted and received by the transmission processing means provided for each load, and set by the setting means And a calculation processing means for calculating the preset cutoff information for each load using the cutoff priority and the suppliable power.

According to the present invention having such a configuration, it is possible to realize a highly reliable load selection and interruption system in which the system can be easily constructed.

[0013]

Embodiments of the present invention will be described below in detail with reference to the drawings. In the following drawings, the same symbols indicate the same or corresponding parts.

FIG. 1 is a configuration diagram of a load selection / interruption system according to one embodiment of the present invention. As shown in the figure, each circuit breaker, that is, a circuit breaker control circuit 20 (20
₁ , 20 ₂ ,...) For each load selection and cutoff unit 10 (1
0 ₁ , 10 ₂ ,...) Are connected in parallel by the transmission line 30. In addition, a handy terminal 40 for setting the priority of selective cutoff and the amount of power that can be supplied by the generator (and the power measurement range of the power converter for power measurement as necessary) is connected. ing.

FIG. 3 is a detailed block diagram of the load selection / interruption unit 10. As shown in FIG. In FIG. 1, reference numeral 1 denotes a power supply unit which supplies control power to each unit. An analog input unit 2 is connected to a power converter for measuring power of the circuit breaker control circuit 20. Reference numeral 3 denotes a digital input unit, which is a state of the load breaker (closed / closed) from the breaker input means of the breaker control circuit 20.
Open) is input. Reference numeral 4 denotes a relay output unit, which outputs a preset as a result of the arithmetic processing to preset output means of the circuit breaker control circuit 20.

Reference numeral 5 denotes an arithmetic processing unit, which performs arithmetic processing based on each set value set by the handy terminal 40 and input from each of the input units 2 and 3, and determines a preset output. Reference numeral 6 denotes a transmission unit which exchanges information with another device such as the handy terminal 40. Reference numeral 7 denotes an address selection switch for identifying each load selection cutoff unit.

Next, this operation will be described with reference to FIG. 3 showing a processing flow and FIG. 4 showing a specific example of data processing.

First, in the handy terminal 40, the priority of load selection and cutoff and the amount of power that can be supplied by the generator are set and input (step S31). Each load shedding unit 1
At 0, the analog input (load power) and digital input (breaker (CB) state, for example, ON ... 1, OFF ...
0) is captured (step S32).

These data are sent by the transmission unit 6 to the arithmetic processing unit 5 of each load shedding unit 10 via the transmission line 30 (step S33). here,
The analog input and the digital input become respective shared data using the address selected by each load selection cutoff unit 10 as an identification number.

Next, as a procedure of the arithmetic processing in the arithmetic processing unit 6 of each load selection / interruption unit 10, first, a system operation pattern is determined from the current state of the circuit breaker and the like (step S34). For example, the pattern differs between the case where power is received from a commercial power supply and the use of a premises generator, and the case where only the premises generator is used. Further, when there are a plurality of generators, the value of the power that can be supplied to the generators changes depending on the number of generators used, and it is necessary to distinguish patterns. In this determination, information from a power reception amount detection unit (not shown) from a commercial power supply and a power generation amount detection unit (not shown) of each generator is transmitted to each load interruption unit 10 via the transmission line 30. And can be determined based on these information.

Next, the current total power is calculated by adding the respective load powers (step S35).

Then, the amount of power to be cut off is calculated by comparing the power that can be supplied by the generator with the current power (step S3).
6). The cutoff power is allocated to each target load based on the priority (step S37). The result is preset output (step S38).

The preset output means of the breaker control circuit 20 of each breaking load outputs the preset output when an accident such as a power failure of a commercial power supply occurs.
Trips at the AND output with the accident output and turns off the circuit breaker
And

Here, a specific example of data processing in the arithmetic processing unit 5 will be described with reference to FIG.

The input and set values are arranged in a data table as indicated by "common data". By processing the data by the processing logic, the data is processed as indicated by “result data”.

For example, in the case of a pattern in which power is received from a commercial power supply and a generator on the premises is used, power that can be generated and supplied (for example, when power reception from the commercial power supply stops, power can be supplied only by the generator on the premises) (Power) is set to 20 [100 KW]. The number of interrupted loads is 5, power 10 of address 1 (interrupted load # 1) of “common data”, CB state 1,
Priority 1 to be interrupted, power 5 at address 2 (interruption load # 2), CB state 1, priority 2, power 7 at address 3 (interruption load # 3), CB state 1, priority 3, address 4
It is assumed that the power of (interruption load # 4) is 15, CB state 1, priority 4, and the power of address 5 (interruption load # 5) is 0, CB state 0, and priority 5.

The current power calculation result is 10 + 5 + 7 + 15 =
37 [100 KW], and the interruption power calculation result is 37-20.
= 17 [100 KW], so the priority of blocking 1 and 2
Alone gives 10 + 5 = 15 [100 KW] and 17 [100 K]
W], and 10 + 5 + 7 =
22 [100 KW] and 17 [100 KW] or more,
The preset output from address 1 (interruption load # 1) to address 3 (interruption load # 3) is set to 1.

As described in detail above, in the present embodiment, a dedicated arithmetic processing controller is not provided as in the prior art, and the load selection and interruption units distributed and arranged for each load interrupter are connected by the transmission line. Since data is exchanged with each other and calculation of the breaking load and selection of the preset output are performed for each load selection breaking unit, the following effects are obtained. 1) In the load selection and breaking unit provided for each breaking load, arithmetic processing is individually performed on the basis of "common data". Therefore, compared with the case where a dedicated arithmetic processing controller is applied as in the past, a dedicated arithmetic processing controller is applied. High system reliability. 2) Basically, only the transmission line needs to be connected between the load selective cutoff units, so that the cost for the construction is reduced. 3) Since the load selection and breaking unit can be housed together with the switchboard that houses the circuit breaker control circuit, there is no need to provide a separate panel for housing the load selection and breaking unit. 4) By standardizing the load selection / interruption unit, it is not necessary to newly create an individual dedicated program when constructing the system. (Only the setting of the unit (for example, the setting of the address) and the setting by the handy terminal need be performed.)

[0029]

As described above, according to the present invention,
The system construction is easy, and a highly reliable load selection and cutoff system can be realized.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a load selection / interruption system according to an embodiment of the present invention.

FIG. 2 is a detailed configuration diagram of a load selection / interruption unit according to one embodiment.

FIG. 3 is a flowchart illustrating a procedure of a process according to the embodiment;

FIG. 4 is an exemplary view for explaining a specific example of data processing according to the embodiment;

FIG. 5 is a configuration diagram of a conventional system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Load selection cut-off unit 20 ... Circuit breaker control circuit 30 ... Transmission line 40 ... Handy terminal 1 ... Power supply unit 2 ... Analog input unit 3 ... Digital input unit 4 ... Relay output unit 5 ... Arithmetic processing unit 6 ... Transmission processing unit 7 … Address selection switch

Claims (1)

[Claims] 1. A setting means for setting a cut-off priority and suppliable power of each load, and exchange of information on the power of each load and the state of the circuit breaker with other loads provided for each load. Transmission processing means for performing, information on the power of each load and the state of the circuit breaker provided and received by the transmission processing means provided for each of the loads, and the interruption priority and the supply possible set by the setting means A load selection / interruption system comprising: an arithmetic processing unit that performs an operation of preset information for selective interruption of each load using electric power.