KR100972841B1 - Auto switching apparatus based on a real-time power flow and a power distributor with the same - Google Patents

Abstract

PURPOSE: An auto switching device based on real-time power flow and a distribution apparatus including the same are provided to efficiently supply preserve power to a load in an power outage of a normal power supply apparatus by using a reserve power supply apparatus. CONSTITUTION: A plurality of breakers(Tr1-Trn) is respectively arranged on an input terminal of a plurality of loads(LD1-LDn). An auto load switch(20) is connected to a normal power supply apparatus(10) or reserve power supply apparatus(12) in order to supply the normal power or reserve power. The reserve power supply apparatus supplies the reserve power of the reserve power contact quantity less than the normal power contact quantity. A load switch(30) controls the operation of the load when the auto load switch is switched in order to supply the reserve power.

Description

Automatic switching apparatus based on a real-time power flow and a power distributor with the same}

The present invention relates to a real-time power current-based automatic switching device and a water distribution facility having the same, and more particularly, to maintain a reserve power contract capacity or a reserve power equipment capacity at a level smaller than the regular power contract capacity or the constant power equipment capacity. The present invention relates to a real-time power current-based automatic switching device and a water distribution facility having the same.

Buildings and factories require water distribution facilities to receive power, and the water distribution facilities include breakers, switchgear, and transformers.

Water distribution equipment needs technology to switch in consideration of load power for effective operation.In this regard, Korea Utility Model Registration No. 20-332957 (Name: Automatic Load Switching Device for Load Power) and Korea Utility Model Registration No. 20-381066 (Name: digital switchgear switch control) has been disclosed.

Korea Utility Model Registration No. 20-332957 discloses a technology that automatically supplies power to the load by automatically switching the load power to the emergency generator power supply when commercial power is not supplied by a power failure, and Korea Utility Model Registration No. 20-381066 Disclosed is a technique for integrating and controlling various circuit breakers necessary for a switchgear.

In general, power supply requires a constant power supply facility for supplying a constant power and a reserve power supply facility for supplying a reserve power to replace it.

The above reserve power can be supplied in place of the regular power in the situation such as repairing a facility for supplying the constant power or an accident in which the regular power is not normally supplied, and supplying the reserve power by replacing the regular power. In order to achieve this, the power distribution facility operates an automatic load switching switch and a breaker.

Normally, the reserve power contract capacity or reserve power supply facilities require contracts and facilities with 100% of the regular power contract capacity or the constant power supply equipment. In this case, the constant power contract capacity and the reserve power contract capacity or the constant power supply are required. Since the capacity of the facility and the reserve power supply facilities are the same, there is no need to adjust the transfer timing by examining the real-time power flow when there is a need to supply the reserve power. In other words, when switching of the power distribution equipment is required, the switching can be easily performed without the need for reviewing the power current.

However, as described above, if the preliminary power supply facility is installed at the same level as the regular power supply facility, the initial facility cost for securing the reserve power capacity is required as the regular power supply facility. Therefore, the cost burden on the facilities installed for power supply is high.

In addition, when the backup power supply facility is designed to have the same capacity as the regular power supply facility, the backup power supply facility can be operated at no load while the regular power supply facility is in operation. Therefore, power loss may occur when the preliminary power supply facility is operated at no load. In this case, problems of social perspective (eg, green energy policy) can be caused.

In addition, the power user should contract for a power supply a reserve power contract capacity of the same capacity as the regular power contract capacity. Therefore, there is a problem that the power user must spend excessively on the reserve power contract capacity.

The present invention is a real-time power current-based automatic switching device that can effectively supply the backup power when the power supply facility is a power outage with a reserve power supply facility of less than the regular power contract capacity and the regular power supply facilities to solve the above problems It is intended to provide.

In addition, the present invention by applying a real-time switching algorithm in synchronization with the switching to replace the regular power to the standby power in the power failure of the power supply of the regular power supply to cut off the non-critical load to a reserve power contract capacity smaller than the regular power contract capacity It is an object of the present invention to provide a real-time power algae-based automatic switching device that smoothly supplies reserve power.

In addition, the present invention is applied to the overload operation algorithm in order to not exceed the overload operation limit in terms of transformer or line in the state that the constant power supply is switched to the reserve power to cut off the critical load from the reserve of capacity smaller than the regular power contract capacity It is an object of the present invention to provide a real-time power algae-based automatic switching device that smoothly supplies reserve power to a power supply facility.

In addition, an object of the present invention is to supply a water distribution equipment having the above-described real-time power current-based automatic switching device.

Real-time power current-based automatic switching device according to the present invention, the breakers are installed independently for a plurality of loads of predetermined importance; Selecting any one of the regular power supply facilities for supplying the regular power of the regular power contracted capacity and the reserve power supply equipment for supplying the reserve power of the reserve power contracting capacity smaller than the regular power contracted capacity, the breaker Automatic load switching switch for supplying to the plurality of load in common through; And when the automatic load transfer switch is switched to supply the reserve power, if the sum of the real-time power consumption for the loads is greater than the reserve power contract capacity, the trip command is sequentially received from the load of low importance according to the real-time transfer algorithm. The circuit breaker of the selected load immediately after the real time switching power by the real-time switching algorithm subtracts the real time power of the selected load from the sum of real time power by the loads currently turned on. If the trip command is generated (break time t = 0) and the circuit breaker subtracts the real time power of the selected load from the sum of real time power by the loads currently turned on, the backup power is less than the reserve power contract capacity. Predetermine the difference between the contracted capacity and the real time power used by the loads currently turned on. Includes; by applying the integration time ever generate the cut-off time, and the load switching device for generating the trip instruction to the blocking time.

Here, it is preferable that the real-time power used is a value accumulated by the real-time power current operation.

The reserve power contracting capacity may be set to 40% to 60% of the regular power contracting capacity, and preferably, the reserve power contracting capacity may be set to 50% of the regular power contracting capacity.

In addition, the facility capacity of the reserve power supply facility may be set to 40% to 60% of the facility capacity of the regular power supply facility, and preferably, the facility capacity of the reserve power supply facility is the facility of the regular power supply facility. It can be set to 50% of the capacity.

In addition, the automatic load transfer switch is provided with a transfer signal due to the power failure of the power supply facility and the internal equipment sound signal to the load transfer device, the load transfer device is the automatic load transfer switch to supply the reserve power. It is preferable to perform the real-time switching algorithm by detecting the state.

The load switching device may generate the trip command sequentially by performing the real-time switching algorithm until the sum of the real-time power used for the loads satisfies the reserve power contract capacity or less.

Real-time power current-based automatic switching device according to the present invention, the constant voltage transformer for supplying power of the constant power contract capacity; A pre-transformer for supplying power with a reserve power contracting capacity smaller than the regular power contracting capacity; Breakers installed independently for a plurality of loads of preset importance; An opening / closing device which selects any one of the normal transformer and the preliminary transformer and commonly supplies the constant power or the reserve power to the plurality of loads through the breakers; And when the switchgear is switched to supply the reserve power, the overload operation algorithm for determining the overload operation state based on the apparent power of the loads until the switch is returned to supplying the regular power. When the trip command is generated sequentially and the installed capacity of the preliminary transformer is less than or equal to the sum of the apparent powers of all the loads according to the overload operation algorithm, '(sum of the apparent powers of all the loads / The first trip command for the first selected load at the first command time generated by calculating the actual capacity of the preliminary transformer) ** overload coefficient for no load of the first selected load, and performing the first trip command for the first selected load. At the first command time, the actual capacity of the preliminary transformer is equal to the apparent power of the current loads. If less than, select the subordinate load according to the importance sequence and calculate '(sum of apparent power for current loads / capacity of the actual pre-transformer) * overload of subordinate load' for the subordinate load. And a load switching device configured to perform a second trip command for the subordinate load at the generated second command time.

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Here, the real-time power used may be a value accumulated by the real-time power current calculation operation.

The reserve power contracting capacity may be set to 40% to 60% of the regular power contracting capacity, and preferably, the reserve power contracting capacity may be set to 50% of the regular power contracting capacity.

In addition, the installation capacity of the pre-transformer may be set to 40% to 60% of the installation capacity of the normal transformer, preferably, the installation capacity of the pre-transformer may be set to 50% of the installation capacity of the normal transformer. have.

In addition, the load switching device may perform the overload operation algorithm by detecting that the switchgear is in a state of supplying the reserve power as information determined to supply the reserve power is provided by the switchgear.

In addition, the switchgear having a real-time power current-based automatic switching device according to the present invention is one of the above-mentioned to switch the supply of a plurality of loads and the constant power and the reserve power to the plurality of loads and to control the supply of the reserve power It includes a real-time power current-based automatic switching device corresponding to the.

According to the present invention, it is possible to effectively supply the spare power to the reserve power contract capacity or the reserve power supply facility having a capacity smaller than the regular power contract capacity in response to the power failure of the power supply facility.

In addition, the present invention can smoothly supply the reserve power with a reserve power contract capacity smaller than the regular power contract capacity by cutting off the non-critical load by the real-time switching algorithm.

In addition, the present invention is controlled so as not to exceed the overload operation limit in terms of transformers or lines in the state in which the constant power supply is switched to the reserve power due to the power failure of the constant power supply equipment smoothly to the reserve power supply capacity of the small reserve power supply equipment Can supply

Accordingly, the present invention can be installed with a smaller capacity than the regular power supply equipment, the initial equipment cost for securing the reserve power capacity can be reduced.

In addition, since the spare power supply facility can be designed with a smaller capacity than the regular power supply facility, power loss can be reduced as the spare power supply facility is operated at no load.

In addition, the power user can reduce the expenditure on the use of power by contracting the regular power contract capacity and the smaller capacity reserve power contract capacity for power supply.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the following embodiments are provided to those skilled in the art to fully understand the present invention, and may be modified in various forms, and the scope of the present invention is limited to the embodiments described below. It doesn't happen. Like numbers refer to like elements in the figures.

In the present invention, the constant power contract capacity refers to the constant power of the maximum capacity that can be used under the contract, and the reserve power contract capacity refers to the reserve power of the maximum capacity that can be used under the contract, and the constant supply equipment refers to a facility that supplies the constant power. That is, the regular supply equipment capacity refers to the maximum continuous power capacity that can be supplied to the constant supply equipment, the reserve supply equipment refers to the equipment to supply the reserve power, the reserve supply capacity is the maximum reserve that can be supplied to the reserve supply equipment. Power capacity refers to the flow of active power and reactive power according to power demand. In the present invention, the real-time power is cumulatively accumulated according to the real-time power current calculation.

Further, the reserve power contracting capacity set in the embodiment of the present invention may be set to 40% to 60% of the regular power contracting capacity, preferably, the reserve power contracting capacity may be set to 50% of the regular power contracting capacity. have.

In addition, the equipment capacity of the reserve power supply equipment set in the embodiment of the present invention may be set to 40% to 60% of the equipment capacity of the constant power supply equipment, preferably the equipment capacity of the reserve power supply equipment is always power It can be set to 50% of the installed capacity of the supply equipment.

1 is a circuit diagram showing an embodiment of a real-time power current-based automatic switching device according to the present invention.

Referring to FIG. 1, the continuous power supply facility 10 and the reserve power supply facility 12 are connected to an automatic load switchgear 20, and the automatic load switchgear 20 is a constant power supply facility 10 or a reserve. It is connected to any one of the power supply facilities 12 to supply power to the loads LD1, LD2 ... LDn. Here, in the embodiment, the preliminary power supply facility 12 is equipped with 50% of the capacity of the regular power supply facility 10 as an example. According to the embodiment, the reserve power contract capacity is also set to 50% of the regular power contract capacity according to the capacity of the reserve power supply facility 12.

The automatic load switching circuit 20 supplies power to each of the loads LD1, LD2 ... LDn in common through the circuit breakers Tr1, Tr2 ... Trn, and each circuit breaker (Tr1, Tr2 ... Trn). ) Is configured one-to-one at the leading end of each of the loads LD1, LD2 ... LDn.

When the power supply facility 10 is always interrupted by a failure or inspection, the real-time power flow-based automatic switching device according to the present invention is connected to the automatic load transfer switch 20 to receive power from the preliminary power supply facility (12) The state is transferred.

In addition, the real-time power flow-based automatic switching device according to the present invention is provided with a load switching device 30 when the automatic load switching switch 20 is switched to supply the reserve power load switching device 30 in synchronization with this And to control the operation.

The load switching device 30 controls the switching of the breakers Tr1, Tr2 ... Trn, and has a configuration for collecting real-time power consumption information from each load.

The load switching device 30 previously stores the importance information for each load, and controls the operation according to the amount of real-time power used in the state in which the automatic load transfer switch 20 is switched.

More specifically, if the real-time power consumption is less than the reserve power contracted capacity, the load switching device 30 is operated below the reserve power contracted capacity by maintaining the switching state until the return to normal power without interrupting the load.

On the contrary, when the real-time power consumption exceeds the reserve power contraction capacity, the load switching device 30 drives a real-time transfer algorithm so that the cumulative accumulation amount due to the real-time power current calculation does not exceed the reserve power contraction capacity. Shut off sequentially to operate below the reserve power capacity.

Here, the cumulative accumulation amount refers to a value obtained by dividing the real time usage by the cumulative time for a certain period, and the real time power consumption P is the total power usage sum of the total load usage as shown in Equation 1 below.

Where Ln is the individual real-time power consumption of the loads LD1, LD2 ... LDn, and the importance of the load is defined in the order of LD1 <LD2 ... <LDn.

The above-described real-time switching algorithm will be described later with reference to FIG. 2.

The automatic load transfer switch 20 provides the transfer signal / SEL and the internal sound signal TS by the power failure of the power supply facility 10 at all times, and the transfer signal / SEL and the internal sound signal TS inside the facility are supplied to the AND gate 22. The load switching device 30 detects that the automatic load switching switch 20 is in the state of supplying the reserve power as an output signal of the end gate 22 and is real-time switching. Perform the algorithm.

As described above, when the transfer is performed in the automatic load transfer switch 20 and the transfer signal / SEL and the internal equipment sound signal TS, which are information about the transfer, are combined in the end gate 22 and transmitted to the load transfer device 30, the load The switching device 30 first executes initialization and adds real-time power P (P = L1 + L2 ... Ln) of all the loads (S10).

When the automatic load transfer switch 20 is switched (S12), it is determined whether the real-time power consumption P is greater than the reserve power contracted power S (S14).

If the real-time power used P is less than the reserve power contracted capacity S, the load switching device 30 does not take any action. This is because the load switching is unnecessary because the real-time power P can be supplied sufficiently even with the reserve power contracted capacity S.

If the real-time power used P is larger than the reserve power contracted capacity S, the load switching device 30 proceeds with the subsequent procedure for controlling excessive load generation.

First, a cutoff time t for a trip command for switching the load LD1 having the least importance is calculated. In order to calculate the interruption time of the load LD1, the relationship between the real time power P of the full load minus the real time power L1 of the load LD1 and the reserve power contract capacity S is determined.

If the value obtained by subtracting the real time power L1 of the load LD1 from the real time power consumption P of the full load is still greater than the reserve power contracted capacity S, the interruption time t = 0 is set and an immediate trip command is provided (S18). The connected breaker Tr1 is opened to cut off the power to the load LD1.

If the value obtained by subtracting the real-time power L1 of the load LD1 from the real-time power consumption P of the full load is less than or equal to the reserve power contracted capacity S, the breaking time t is set according to Equation 2 below, and the trip command is In operation S20, the breaker Tr1 is opened at the time when the trip command is provided, and the power supplied to the load LD1 is cut off.

Here, M is a preset cumulative integration time, can be set by the experimental value, 15 minutes can be applied for the embodiment.

The above-described blocking time t is for adjusting the cumulative accumulation amount used during the cumulative integration time to the reserve power contract capacity.

In other words, if the real time power P of the full load minus the real time power L1 of the load LD1 is still greater than the reserve power contract capacity S, set the breaking time t = 0 and immediately generate a trip command for the load LD2 having the next lowest importance. Judge.

If the value obtained by subtracting the real time power L1 of the load LD1 from the real time power P of the full load is less than the reserve power contracted capacity S, the current real time power is maintained from t = 0 to the cutoff time t. Shut off LD1. Then, the real-time used power P becomes an integrated value from t time until the load L1 consumes power and from t time to 15 minutes when the load L1 does not consume power equal to the reserve power contract capacity S.

That is, as shown in FIG. 3, the real-time power P may be changed based on the cutoff time t, and the hatched portions on both sides of the cutoff time t are equal to each other as integrated values.

If power is not supplied to the load LD1 according to the trip commands of steps S18 and S20 described above, the real time power is replaced by P1 = P-L1. (S22) Here, P1 is the real time use of the entire load excluding the interrupted load LD1. Power.

Thereafter, it is determined whether the real-time used power P1 by the loads which are not interrupted at present is larger than the reserve power contracted capacity S (S24).

If the real time power P1 is less than the reserve power contracted capacity S, the load switching device 30 does not take any action.

When the real-time power used P1 is larger than the reserve power contracted capacity S, the load switching device 30 performs a subsequent procedure for controlling the load.

First, a cutoff time for a trip command for switching the load LD2 of low importance is calculated. In order to calculate the interruption time of the load LD2, it is determined the relationship between the real time power P1 of the current full load minus the real time power L2 of the load LD2 and the reserve power contract capacity S. (S26)

If the real time power P1 of the current load minus the real time power L2 of the load LD2 is still greater than the reserve power contracted capacity S, the breaking time t = 0 is set and an immediate trip command is provided. (S28) Then, the load LD2 The breaker Tr2 connected to it opens, breaking the power to the load LD2.

If the value obtained by subtracting the real-time power L1 of the load LD2 from the real-time power consumption P1 of the full load is less than or equal to the reserve power contracted capacity S, the breaking time t is set according to Equation 3 below. In operation S30, the breaker Tr2 is opened at the time when the trip command is provided, and the power supplied to the load LD2 is cut off.

If power is not supplied to the load LD2 according to the trip commands of steps S28 and S30 described above, the real time power is replaced by P2 = P1-L2. (S32) Here, P2 is the total load excluding the interrupted loads LD1 and L2. Real time power consumption.

As described above, the subsequent process is performed to sequentially generate trip commands in order of loads of low importance until the real-time power of the current full load satisfies the condition below the reserve power contract capacity S. (S34)

On the other hand, Figure 4 is an embodiment of the present invention the reserve power supply facility capacity is smaller than the regular power supply facility capacity in the 2 to 3 bank, a circuit breaker switching circuit for operating within the overload operation limit of the real-time power flow calculation-based water distribution equipment .

4 has a bank including loads LD1 to LD3 and a bank including loads LD4 to LD6.

In the embodiment of Figure 4 NT1, NT2 is a constant transformer and ST is a pre-transformer. 52S1 is a breaker installed at the inlet end side of the constant transformer NT1, 52S2 is a breaker installed at the inlet end side of the constant transformer NT2, and 52SP is a breaker installed at the inlet end side of the preliminary transformer ST. And, 52P1 is a circuit breaker installed on the supply side of the constant transformer NT1, 52P2 is a circuit breaker installed on the supply side of the constant transformer NT2, 52SS is a circuit breaker installed on the supply side of the pre-transformer ST.

A circuit breaker 52T1 and a circuit breaker 52T2 are connected in parallel to a supply terminal of the breaker 52SS, and an input terminal of the breakers R1, R2, and R3 connected to the loads LD1, LD2, and LD3 forming a bank is respectively connected to the supply terminal of the breaker 52T1. Commonly connected, the supply terminal of the circuit breaker 52T2 is commonly connected to the circuit breakers R4, R5, and R36 which are connected to the loads LD4, LD5, and LD6 which form another bank.

In addition, load LD1 to LD6 corresponding to each of the circuit breakers R1 to R6 are independently connected.

The embodiment of FIG. 4 illustrates that the load switching device 40 is configured in one bank to explain the switching of the load, and the load switching device 40 is based on the apparent power of each load, i.e., the real-time working power. It is configured to output the trip commands Tr1 to Tr3 for tripping the breakers R1 to R3 for the loads LD1 to LD3 of the corresponding bank while collecting the information KVA1, KVA2, KVA3.

Here, the circuit breakers 52P1, 52T1, 52SP, and 52SS correspond to the switchgear which selects any one of the constant transformer NT1 and the preliminary transformer ST to supply the normal power or the reserve power to the loads LD1 to LD3 through the breakers R1 to R3 in common. do. This switchgear can be understood as a configuration corresponding to the automatic load switching switch of FIG.

In addition, the load switching device 40 may use the switching information of the breakers included in the switchgear as the information for determining that the switchgear supplies the reserve power, and the switchgear determines that the switchgear supplies the reserve power. As the information, the transfer signal / SEL by the power failure of the constant voltage transformer may be further used.

 In the above-described configuration, when the constant transformer NT1 is out of power by failure or inspection, the load switching device 30 compares the capacity of the pre-transformer ST with the sum of the reserve power contract capacity of the loads LD1 to LD3.

If the capacity of the pre-transformer ST is equal to or greater than the sum of the reserve power contract capacities of the constant transformer NT1, the breakers 52SP, 52SS, and 52T1 are closed to load the pre-power using the pre-transformer ST to the constant-transformer NT1. It supplies to LD1 thru LD3.

Then, if the capacity of the pre-transformer ST is less than the preliminary power contract capacity of the loads LD1 to LD3 depending on the constant transformer NT1, the breakers 52SP, 52SS, and 52T1 are closed to load the pre-power using the pre-transformer ST to the constant transformer NT1. While supplying to LD1 to LD3, the overload operation algorithm is driven so as to be within the overload operation limit of the preliminary transformer ST by real-time power current operation.

The above-described overload operation algorithm will be described later with reference to FIG. 5, and the overload operation algorithm is operated with reference to the overload coefficient table of Table 1 below.

Driving time Overload Factor: K No load (K1) 100% load (K3) 5 minutes 2.0 1.4 30 minutes 1.5 1.2 1 hours 1.31 1.11 2 hours 1.21 1.1 4 hours 1.15 1.05 8 hours 1.08 1.01

Meanwhile, an overload driving algorithm applied to the embodiment of FIG. 4 will be described with reference to FIG. 5.

Each circuit breaker included in the switchgear provides information determined to supply the reserve power, and the information determined to supply the reserve power is provided to the load switching device 40 in the same manner as in the embodiment of FIG. The load switching device 40 detects the state of supplying the reserve power as information determined to supply the reserve power. For reference, a gate configuration for providing information determined to supply spare power to the load switching device 40 has been omitted.

As described above, when each breaker included in the switchgear is switched to a state for supplying spare power, the load switching device 40 executes an overload operation algorithm until returning to supplying constant power.

The load switching device 40 performs an overload operation algorithm that determines the overload operation state based on the apparent power of the loads, and generates trip commands sequentially from the load having low importance.

To this end, the load switching device 40 performs an initialization step (S50) for obtaining the sum A (A = AL1 + AL2 + AL3) of the apparent powers for the entire load, and if the breakers of the switchgear are switched (S52), It is determined whether the installed capacity T 'of the preliminary transformer ST is equal to or less than the sum A of the apparent powers for all the loads (S54).

Here, the actual capacity T 'of the pre-transformer ST may be defined by Equation 4 below.

Here, T is the installed capacity of the pre-transformer ST (KVA), KVA is a unit for displaying the apparent power.

As described above, the actual capacity T 'of the preliminary transformer ST may vary according to environmental factors.

If the actual capacity T 'of the preliminary transformer ST in step S54 is greater than the sum of the apparent powers for the entire load, the load switching device 40 does not take any action.

Alternatively, in step S54, if the actual capacity T 'of the preliminary transformer ST is equal to or less than the sum of the apparent powers for all the loads, the breaking time t is calculated and a trip command for the load LD1 having the least importance is executed.

The interruption time t for the trip command for the load LD1 may be calculated as shown in Equation 5 below.

Where K1 is the overload factor for the no load of the load LD1.

The overload has a capacity margin of 1% of the capacity when the ambient temperature drops to 1 ℃ based on 30 ℃, and a 1% capacity of the capacity when the temperature rise relative to the winding temperature is 1 ℃ below the standard value. The overload coefficients (K) for each load can be divided into one for no load (K1) and one for 100% load (K3), and the overload coefficients for no load K1 and 100% load depending on the load condition. The overload factor K3 has a difference. The overload coefficient K may be prepared as a lockup table according to the experimental value as shown in Table 1, and the overload coefficient K1 for no load forms a curve between t-K1 as shown in FIG. 6 and the overload coefficient K3 for 100% load is A curve between t-K3 is formed as shown in FIG. 7.

On the other hand, the interruption time t for the trip command for the load LD1 may be calculated by the above Equation 5, and the trip command is performed at the calculated interruption time (S56).

When the trip command is executed, since the load LD1 is in the interrupted state, the sum A of the total apparent powers is replaced by A1 excluding the interrupted load LD1 (S58).

Thereafter, if the actual capacity of the preliminary transformer T 'is greater than the sum of the apparent powers of the current loads A1 at the breaking time for the first selected load LD1, the load switching device 40 does not take any action.

However, if the actual capacity of the preliminary transformer T 'is less than or equal to the sum of the apparent powers for the current loads A1 at the cutoff time for the first selected load LD1 (S60), then the trip command for the subordinate load LD2 is calculated at the arithmetic cutoff time t. (S62)

The interruption time for performing the trip command for the subordinate load LD2 may be calculated as in Equation 6.

Where K3 is the overload factor for 100% load of the load LD2.

The application of the overload coefficient for no load for the load LD1 reflects that the pre-transformer ST does not drive the load at the time of calculating the breaking time for the load LD1, and the overload coefficient for 100% load is applied to the load LD2. Since the pre-transformer ST bears the load at the time of calculating the breaking time for LD2, it is assumed that the load is arbitrarily 100%.

 When the trip command to the subordinate load LD2 is performed as described above, since the load LD2 is in the cutoff state, the sum A1 of the total apparent powers is replaced by the blocked loads LD1 and A2 excluding the LD2 (S64).

Subsequently, the sequential trip command is executed for the less important load until the actual pre-transformer capacity satisfies a condition that is greater than the sum of the total apparent powers of the currently operating loads (S66).

Here, the cutoff time for the trip command may be calculated by the method of Equation 6 described above.

As described above, the present invention can supply the reserve power with a reserve power contract capacity of a smaller capacity than the regular power contract capacity when the power supply facility for supplying the regular power is switched off in the state of supplying the reserve power due to the power failure.

In addition, the present invention can supply the reserve power to a reserve power supply of a smaller capacity than the regular power supply facilities.

In addition, the present invention can smoothly supply the reserve power with a reserve power contract capacity smaller than the regular power contract capacity by cutting off the non-critical load by applying the power current-based real-time switching algorithm.

In addition, the present invention can apply the power current-based overload operation algorithm to cut off the non-critical load to supply the reserve power within the overload operation limit.

As mentioned above, although preferred embodiment of this invention was described in detail, this invention is not limited to the said embodiment, A various deformation | transformation by a person of ordinary skill in the art within the scope of the technical idea of this invention is carried out. This is possible.

1 is a circuit diagram showing an embodiment of a real-time power current-based automatic switching device according to the present invention.

2 is a circuit diagram illustrating an embodiment in accordance with the present invention applied to multiple banks.

3 is a graph representing the amount of integration against the blocking time.

Figure 4 is a flow chart showing a real-time switching algorithm of the real-time power current-based automatic switching device according to the present invention.

5 is a flowchart illustrating an overload operation algorithm of a real-time power current-based automatic switching device according to the present invention.

6 is a K1-t curve showing the overload coefficient of the no-load state of Table 1

7 is a K3-t curve showing the overload coefficient of the overload condition of Table 1

Claims (14)

Breakers installed independently for a plurality of loads of preset importance; Selecting any one of the regular power supply facilities for supplying the regular power of the regular power contracted capacity and the reserve power supply equipment for supplying the reserve power of the reserve power contracting capacity smaller than the regular power contracted capacity, the breaker Automatic load switching switch for supplying to the plurality of load in common through; And When the automatic load transfer switch is switched to supply the reserve power, if the sum of the real-time power consumption for the loads is greater than the reserve power contract capacity, the trip command is sequentially generated from the load of low importance according to the real-time transfer algorithm. If the value obtained by subtracting the real time power consumption of the selected load by the sum of real time power consumption by the loads in which the breaker is currently turned on by the real time switching algorithm exceeds the reserve power contract capacity, the breaker of the selected load is immediately added. If a trip command is generated (break time t = 0) and the circuit breaker is a sum of real-time power used by loads currently turned on, minus real-time power of the selected load is less than the reserve power contract capacity.

The blocking time is generated according to (L is the real-time power consumption of the selected load, S is the reserve power contract capacity, P is the real-time power consumption of the entire load, M is a predetermined cumulative integration time), Real-time power current-based automatic switching device comprising a; load switching device for generating the trip command. The method of claim 1, The reserve power contract capacity is a real-time power flow based automatic switching device is set to 40% to 60% of the regular power contract capacity. The method of claim 2, The reserve power contract capacity is set to 50% of the regular power contract capacity real-time power flow based automatic switching device. The method of claim 1, The facility capacity of the reserve power supply facility is a real-time power flow current based automatic switching device is set to 40% to 60% of the capacity of the regular power supply facility. The method of claim 4, wherein And a facility capacity of the reserve power supply facility is set to 50% of the facility capacity of the regular power supply facility. The method of claim 1, The automatic load switching switch is a state in which the automatic load switching switch is to supply the reserve power as the transfer signal due to the power failure of the constant power supply equipment and the internal equipment sound signal are provided to the load switching device in the automatic load switching switch. Real-time power algae-based automatic switching device for sensing and performing the real-time switching algorithm. The method of claim 1, The load switching device is a real-time power flow-based automatic switching device for generating a trip command sequentially by performing the real-time switching algorithm until the sum of the real-time power used for the load satisfies less than the reserve power contract capacity. A constant transformer for supplying power of a constant power contract capacity; A pre-transformer for supplying power with a reserve power contracting capacity smaller than the regular power contracting capacity; Breakers installed independently for a plurality of loads of preset importance; An opening / closing device which selects any one of the normal transformer and the preliminary transformer and commonly supplies the constant power or the reserve power to the plurality of loads through the breakers; And When the switchgear is switched to supply the reserve power, the overload operation algorithm is performed to determine the overload operation state based on the apparent power of the loads until the power supply is returned to supplying the standby power. A trip command is generated, and when the actual capacity of the preliminary transformer is less than or equal to the sum of the apparent powers of all the loads by the overload operation algorithm, the sum of the apparent powers of all the loads / the Actual capacity of the preliminary transformer) * and perform the first trip command for the first selected load at the first command time generated by calculating the overload coefficient for the no load of the first selected load, and the first for the first selected load. The actual capacity of the actual pre-transformer at one command time is the sum of the apparent power for the current loads. If only the subordinate load is selected according to the importance sequence, and calculates '(sum of apparent powers for current loads / capacity of the actual pre-transformer) * overload of subordinate load' for the subordinate load. And a load switching device configured to perform a second trip command for the subordinate load at the generated second command time. The method of claim 8, The reserve power contract capacity is a real-time power flow based automatic switching device is set to 40% to 60% of the regular power contract capacity. The method of claim 9, The reserve power contract capacity is set to 50% of the regular power contract capacity real-time power flow based automatic switching device. The method of claim 8, The capacity of the pre-transformer is a real-time power current-based automatic switching device is set to 40% to 60% of the capacity of the permanent transformer. The method of claim 11, The equipment capacity of the pre-transformer is a real-time power algae-based automatic switching device is set to 50% of the capacity of the permanent transformer. The method of claim 8, And the load switching device detects that the switching device is in the state of supplying the reserve power and performs the overload operation algorithm. A plurality of loads; And A water distribution facility comprising a real-time power current-based automatic switching device according to any one of claims 1 to 13 for switching the supply of the regular power and the reserve power to the plurality of loads and to control the supply of the reserve power.

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