JP5950489B1 - Load testing equipment - Google Patents

Abstract

The load test apparatus includes a first input unit connected to a first test target power source, a second input unit connected to a second test target power source having a small rated voltage, a first resistance unit, and a second resistor having a small rated capacity. A unit and a bidirectional transformer that steps down the voltage of power supplied from the first power source to be tested and boosts the voltage of power supplied from the second power source to be tested. In the load test of the first test target power source connected to the first input unit, power is supplied from the first test target power source to the first resistance unit in a state where neither the step-up nor the step-down is performed. In the load test of the second test target power source connected to the second input unit, power is supplied to a part of the resistor group constituting the second resistance unit in the stepped down state, from the second test target power source, Power is supplied to a part of the resistor group constituting the first resistance unit in a state where the voltage is boosted by the bidirectional transformer, and power is supplied to the second resistance unit in a state where the voltage is neither boosted nor lowered.

Description

  The present invention relates to a load test apparatus.

  Conventionally, as disclosed in Patent Document 1, a load test apparatus that performs a load test on a generator includes a transformer.

JP 2011-169702 A

  However, since the voltage of the electric power from the power source to be tested is applied to the resistor in a state where all the voltage is transformed, there is a problem that the transformer becomes large.

  Accordingly, an object of the present invention is to provide a load test apparatus capable of performing a load test on a power supply to be tested with different voltages without increasing the size of the transformer.

  A load test apparatus according to the present invention includes a first input unit connected to a first test target power source, a second input unit connected to a second test target power source having a smaller rated voltage than the first test target power source, A first resistor unit provided with a plurality of resistor groups having the above resistors and a second resistor unit having a plurality of resistor groups having one or more resistors and having a smaller rated capacity than the first resistor unit The voltage of the power supplied from the first test target power supply via the first input unit, and the voltage of the power supplied from the second test target power supply via the second input unit. Load test apparatus used for performing a load test while adjusting the load amount by changing the number of resistor groups to which a voltage is applied among the resistor groups in the first resistor unit and the second resistor unit. The first input unit In the load test of the connected first test target power supply, when applying the maximum load, power is supplied from the first test target power supply to the first resistance unit in a state where neither step-up nor step-down is performed, This is a load test of the second test target power source in which power is supplied to a part or all of the resistor group constituting the second resistor unit in a state where the voltage is stepped down by the bidirectional transformer and connected to the second input unit. When the maximum load is applied, power is supplied from the second test target power source to a part of the resistor group constituting the first resistance unit in a state where the voltage is boosted by the bidirectional transformer. In this state, power is supplied to the second resistance unit.

When performing a high voltage load test, not only the resistor group of the first resistance unit but also a bidirectional transformer for the purpose of step-down and mainly used for a load test of a low voltage second test target power source. Since part or all of the resistor group of the two-resistance unit is used, it is possible to perform a load test with a large load compared to a mode in which the second resistance unit is not used.
When performing a low-voltage load test, not only the resistor group of the second resistor unit but also a bidirectional transformer is used for the purpose of boosting and is mainly used for a load test of a high-voltage first test target power source. Since a part of the resistor group of one resistance unit is also used, it is possible to perform a load test with a large load compared to a configuration in which the first resistance unit is not used.

  In addition, the resistor group (load) that applies the boosted voltage and the resistor group (load) that applies the stepped-down voltage are part of the resistor group that performs the load test, so all the resistor groups Use a transformer with a smaller rated capacity (bidirectional transformer) compared to a mode that applies a voltage that is boosted to a voltage or a mode that applies a voltage that is stepped down to all resistors. It becomes possible to do.

  In addition, since the bidirectional transformer is used as both a step-up transformer and a step-down transformer, a low-voltage resistance unit (second resistance unit) is used during a high-voltage load test. At the time of the test, it becomes possible to minimize the size of the transformer when utilizing the high-voltage resistance unit (first resistance unit).

  Preferably, a first circuit breaker that performs on / off control of power supply from the first power source to be tested to the first resistance unit and the bidirectional transformer through the first input unit, and the second test through the second input unit. A second circuit breaker that performs on / off control of power supply from the target power source to the second resistance unit and the bidirectional transformer, and a first test target power source to the first resistance unit and the bidirectional transformer via the first input unit. When the power supply is performed, the second circuit breaker is turned off, and power is supplied from the second test target power source to the second resistance unit and the bidirectional transformer via the second input unit. And an interlock circuit for turning off the first circuit breaker.

  Even if the power supply to be tested is connected to both the first input section and the second input section due to miswiring or misoperation due to the interlock circuit, the circuit breaker for the first protection circuit and the second protection circuit are disconnected. One of the transformers is turned off to interrupt the current flow and protect the subsequent bidirectional transformer and the like.

  Preferably, the first resistance unit and the second resistance unit are configured when power is supplied from the first test target power source to the first resistance unit and the bidirectional transformer via the first input unit. Regardless of the operation state of the operation switch for selecting the resistor group used for the load test among the resistor groups to be operated, the load test of the first test target power source among the resistor groups constituting the second resistance unit is performed. Even when the maximum load is applied, power supply to unused resistor groups is cut off, and power is supplied from the second test target power source to the second resistance unit and bidirectional transformer via the second input section. Power to the resistor group that is not used even when the maximum load is applied in the load test of the second test target power source among the resistor group constituting the first resistance unit, regardless of the operation state of the operation switch. Shut off supply Further comprising a control device.

  Preferably, the rated voltage of the second test target power supply is 1/5 or less of the rated voltage of the first test target power supply.

  Preferably, the rated capacity of the second resistance unit is 1/3 or less of the rated capacity of the first resistance unit.

  More preferably, the rated capacity of the resistor group constituting the first resistor unit, which is used for the load test of the second test target power supply, is smaller than the rated capacity of the resistor group constituting the second resistor unit. .

  Preferably, among the resistor groups constituting the first resistor unit and the second resistor unit, an operation switch for selecting a resistor group used for a load test and a type of a power source to be tested are selected. An operation unit having a mode switch to be used, and when the mode switch is set to a first use mode for performing a load test of the first power source to be tested via the first input unit, Regardless of the operation state, the power supply to the resistor group that is not used in the first use mode is cut off from the resistor group constituting the second resistor unit, and the mode switch is connected to the second input unit via the second input unit. 2 When the second use mode for performing a load test of the power source to be tested is set, the resistor group constituting the first resistor unit is not used in the second use mode regardless of the operation state of the operation switch. Further comprising a control device for interrupting the power supply to the resistor group.

  Preferably, in the resistor group constituting the second resistance unit, the rated capacity of one used for the load test of the first test target power supply is three quarters or less of the capacity of the first test target power supply. .

  As described above, according to the present invention, it is possible to provide a load test apparatus capable of performing a load test on a test target power supply having a different voltage without increasing the size of the transformer.

It is a schematic diagram which shows the structure of the load test apparatus in this embodiment. It is a schematic diagram which shows the connection state of a 1st resistance unit and an operation part. It is a schematic diagram which shows the connection state of a 2nd resistance unit and an operation part. It is a figure which shows the switch of an operation part. It is a figure which shows the flow of the electric current at the time of 1st test mode. It is a figure which shows the flow of the electric current at the time of a 2nd test mode. It is a figure which shows the flow of the electric current at the time of a 3rd test mode. It is a schematic diagram of the load test apparatus in the case of performing control which interrupts | blocks the electric power supply to a one part resistor group from a circuit breaker. It is a schematic diagram which shows the connection state of the 1st resistance unit of a load test apparatus, an operation part, etc. in the case of performing control which interrupts | blocks the electric power supply to a one part resistor group from a circuit breaker. It is a schematic diagram which shows the connection state of the 2nd resistance unit of a load test apparatus, an operation part, etc. in the case of performing control which interrupts | blocks the electric power supply to a one part resistor group from a circuit breaker.

Hereinafter, the present embodiment will be described with reference to the drawings. The load test apparatus 1 in this embodiment includes a first input unit 10a, a second input unit 10b, a first protection circuit 20a, a second protection circuit 20b, an interlock circuit 30, a bidirectional transformer 40, and a first resistance unit 50a. The second resistance unit 50b and the operation unit 60 are provided.
The load test apparatus 1 is used to perform a load test while changing the number of resistor groups (of the first resistor unit 50a and the second resistor unit 50b) to which the test target power supply applies voltage, thereby adjusting the load amount. Is done.

The first input unit 10a is an input terminal for connecting a high-voltage test target power source (first test target power source, rated voltage: 6.6 kV).
The second input unit 10b has a lower rated voltage than the first test target power source (for example, 1/5 or less), a low voltage test target power source (second test target power source, rated voltage: 400V, third test target power source, rated voltage). : 200V).

The first protection circuit 20a includes a zero-phase-sequence current transformer (ZCT), a ground fault relay (Ground Relay (GR)), a power meter (Wattmeter (WM)), an overcurrent relay (Over Current relay (OCR), instrument transformer (Voltage Transformer (VT)), vacuum circuit breaker (Vacuum Circuit Breaker (VCB), first circuit breaker), instrument current transformer (Current Transformer (CT)) Then, the amount of power from the high-voltage test target power source connected to the first input unit 10a is measured, or the power from the test target power source connected to the first input unit 10a when a ground fault or overcurrent occurs. Or shut off the supply.
The vacuum circuit breaker of the first protection circuit 20a performs on / off control of power supply from the first test target power source to the first resistance unit 50a and the bidirectional transformer 40 via the first input unit 10a.

The second protection circuit 20b is composed of an instrument transformer (Voltage Transformer (VT)), a wattmeter (Wattmeter (WM)), a circuit breaker (Molded Case Circuit Breaker (MCCB)), an instrument transformer. The second input unit has a current transformer (CT) and measures the amount of power from the low-voltage test target power source connected to the second input unit 10b, or when a ground fault or overcurrent occurs. The power supply from the power source to be tested connected to 10b is cut off.
The circuit breaker for wiring of the second protection circuit 20b is configured to turn on / off the power supply from the second test target power source or the third test target power source to the second resistance unit 50b or the bidirectional transformer 40 via the second input unit 10b. Take control.

  The interlock circuit 30 is connected between the vacuum circuit breaker of the first protection circuit 20a and the wiring circuit breaker of the second protection circuit 20b.

  The interlock circuit 30 is connected to the second protection circuit 20b when power is supplied from the first test target power source to the first resistance unit 50a and the bidirectional transformer 40 via the first input unit 10a. The first protection is provided when the circuit breaker is turned off and power is supplied from the second test target power source to the second resistance unit 50b or the bidirectional transformer 40 via the second input unit 10b. The vacuum circuit breaker of the circuit 20a is turned off.

  Even when the power supply to be tested is connected to both the first input unit 10a and the second input unit 10b due to erroneous wiring or operation by the interlock circuit 30, the vacuum circuit breaker and the second protection circuit of the first protection circuit 20a One of the wiring breakers 20b is turned off to cut off the current flow and protect the subsequent bidirectional transformer 40 and the like.

  The bidirectional transformer 40 is a transformer capable of both stepping up and stepping down, and steps down the voltage of the power supplied from the first test target power source via the first input unit 10a, and the second input unit 10b. Then, the voltage of the power supplied from the second test target power supply is boosted.

  In the present embodiment, the bidirectional transformer 40 reduces the voltage applied from the first test target power source connected to the first input unit 10a from 6600V to 400V, and the second test connected to the second input unit 10b. An example in which the voltage applied from the target power supply is raised from 400V to 6600V is shown.

The first resistance unit 50a has a plurality of sets of resistor groups and relays provided with one or more resistors.
From the first test target power source connected to the first input unit 10a, a voltage that is neither boosted nor reduced is applied to the resistor group constituting the first resistance unit 50a, and the second input unit 10b is applied with a voltage. From the connected second test target power source, a boosted voltage is applied to a part of the resistor group constituting the first resistance unit 50a via the bidirectional transformer 40.

In the present embodiment, an example in which 24 sets of resistor groups and relays having a rated capacity of 100 kW are provided (first high-voltage relay SH ₀₁ to 24th high-voltage relay SH ₂₄ , first high-voltage resistor group) RH ₀₁ to 24th high voltage resistor group RH ₂₄ , see FIG. 2).

The first resistance unit 50a is mainly used for performing a load test of the first test target power source of high voltage (6600V) connected to the first input unit 10a. The resistor group RH ₂₁ to the 24th high voltage resistor group RH ₂₄ ) are also used for performing a load test of the low voltage (400V) second test target power source connected to the second input unit 10b ( (See FIG. 6).

  Among the resistor groups constituting the first resistance unit 50a, the rated capacity of the resistors used for the load test of the second test target power source (the above-mentioned part of the resistor group) constitutes the second resistor unit 50b. It is smaller than the rated capacity of the resistor group.

The second resistance unit 50b has a plurality of sets of resistor groups and relays provided with a plurality of resistors, and has a smaller rated capacity (for example, 1/3 or less) than the first resistance unit 50a.
From the first test target power source connected to the first input unit 10a, a part or all of the resistor group constituting the second resistance unit 50b is stepped down via the bidirectional transformer 40. A voltage to which the voltage is applied and the test target power supply connected to the second input unit 10b is not boosted or lowered is applied to the resistor group constituting the second resistance unit 50b.

In this embodiment, four sets of resistor groups and relays with a rated capacity of 100 kW, four sets of resistor groups and relays with a rated capacity of 50 kW, and a set of resistors and relays with a rated capacity of 20 kW are set. 3 sets, an example in which two sets of resistor groups and relays with a rated capacity of 10 kW and two sets of resistor groups and relay sets with a rated capacity of 5 kW are provided (first low-voltage relay SL ₀₁ to No. 1 15 low-voltage relay SL ₁₅ , first low-voltage resistor group RL ₀₁ to 15th low-voltage resistor group RL ₁₅ , see FIG.

The second resistance unit 50b is mainly used to perform a load test of the second test target power source and the third test target power source of low voltage (400V or 200V) connected to the second input unit 10b. Alternatively, all of the resistor groups (a part of the twelfth low-voltage resistor group RL ₁₂ to the fifteenth low-voltage resistor group RL _{15 in the} present embodiment) are high-voltage (6600 V) connected to the first input unit 10a. It is also used to perform a load test of the first test target power source (see FIG. 5).

  When a generator with a relatively low rotational speed, such as a diesel generator, is used as the first test target power source, the second resistance unit is set so that the rated capacity is 3/4 or less of the capacity of the first test target power source. It is desirable to select the resistor group used in the load test at 50b.

  The first resistor unit 50a and the second resistor unit 50b are provided with a cooling fan (not shown) for cooling each resistor group.

  The resistors of the resistor group constituting the first resistor unit 50a and the second resistor unit 50b may be a sheathed heater in which a nichrome wire is covered with a metal sheath (sheath), a storage battery, or a liquid resistor. (In this case, a cooling fan is unnecessary).

The operation unit 60 selects an operation group (first operation switch for high voltage H ₀₁ ) for selecting a group of resistors used in the load test (adjusting the load amount) from among the group of resistors constituting the first resistance unit 50 a. To the 24th high voltage operation switch H ₂₄ ) and the resistor group used for the load test among the resistor groups constituting the second resistance unit 50b (adjustment load amount). 1 low pressure operation switch L ₀₁ to 15th low pressure operation switch L ₁₅ ) and a mode switch 61 (see FIG. 4).

The first high pressure operation switch H ₀₁ to the 24th high pressure operation switch H ₂₄ are slide type (or toggle type or push button type) operation switches, and are relays (first high voltage) of the resistor group of the first resistance unit 50a. a switch for performing on-off control of the use resistor group _{RH 01} ~ 24 high-voltage resistor group _{RH 24} each of the first high-pressure relay _{SH 01} ~ 24 pressure relay _{SH 24).}
When the first high-pressure operation switch H ₀₁ to the ON state, the first high-pressure relay SH ₀₁ of the first high-voltage resistor group RH ₀₁ is in the on state (conducting state), the first high-pressure resistor group RH _{In 01} , the current from the power supply to be tested connected to the first input unit 10a or the second input unit 10b can be made to flow (see FIG. 4).
The second high-pressure operating switches _{H 02} ~ 24 for high pressure operation switch _{H 24} is also similar, when turned on, the second high-pressure relay _{SH 02} ~ 24 pressure relay _{SH 24} of the corresponding resistor group on The state (conducting state) is set, and a current from the power supply to be tested connected to the first input unit 10a or the second input unit 10b can flow through the resistor group.

The first low pressure operation switch L ₀₁ to the fifteenth low pressure operation switch L ₂₄ are slide type (or toggle type or push button type) operation switches, and relays (first low pressure) of the resistor group of the second resistance unit 50b. The resistor group RL ₀₁ to the fifteenth low voltage resistor group RL ₁₅ are switches for performing on / off control of the first low voltage relay SL ₀₁ to the fifteenth low voltage relay SL ₁₅ ).
When the first low-pressure operation switch L ₀₁ to the ON state, the first low-pressure relay SL ₀₁ of the first low-pressure resistor group RL ₀₁ is in the on state (conducting state), the first low-pressure resistor group RL _{In 01} , the current from the power source to be tested connected to the first input unit 10a or the second input unit 10b can be made to flow.
Similarly, the second low-pressure operation switch L ₀₂ to the fifteenth low-pressure operation switch L ₁₅ are turned on, and the second low-pressure relay SL ₀₂ to the fifteenth low-pressure relay SL _{15 of} the corresponding resistor group are turned on. The state (conducting state) is set, and a current from the power supply to be tested connected to the first input unit 10a or the second input unit 10b can flow through the resistor group.

The mode switch 61 is used to turn on / off the load test apparatus 1 and to select the type of power source to be tested (mode switching), and has a first rotation position P1 to a fourth rotation position P4.
When performing a load test on a three-phase AC generator (first test target power supply) having a rated voltage of 6600 V, the rotational position of the mode switch 61 is adjusted to the first rotational position P1.
When performing a load test of a three-phase AC generator (second test target power supply) with a rated voltage of 400 V, the rotational position of the mode switch 61 is adjusted to the second rotational position P2.
When performing a load test of a three-phase AC generator (third test target power supply) having a rated voltage of 200 V, the rotational position of the mode switch 61 is adjusted to the third rotational position P3.
When turning off the load test apparatus 1, the rotational position of the mode switch 61 is adjusted to the fourth rotational position P4.

When the rotation position of the mode switch 61 is set to the first rotation position P1, that is, when the load test apparatus 1 is set to the first use mode for performing the load test of the first test target power supply, the first protection circuit 20a The vacuum circuit breaker is turned on (a state in which power from the first power source to be tested connected to the first input unit 10a is supplied to the first resistance unit 50a, etc.), and the first resistance unit 50a and the second resistance unit 50b cooling fan is driven, based on the operation state of the first high-pressure operation switch _{H 01} ~ 24 and high pressure operation switch _{H 24} operation 12 for the low pressure switch _{L 12} ~ 15 low-pressure operation switch _{L 15,} the 1st high-voltage resistor group RH ₀₁ to 24th high-voltage resistor group RH _24, each of the first high-voltage relay SH ₀₁ to 24th high-voltage relay SH ₂₄ , and the 12th low-voltage resistor Off control of the group _{RL 12} ~ 15 relay _{SL 12} ~ 15 low relay _{SL 15} for 12 low-pressure resistor group _{RL 15} of each lower pressure is carried out (see FIG. 5).
FIG. 5 shows, in bold lines, power lines from the first power source to be tested to the resistor group that can be supplied with power.

In this case, the first test target power supply is used so that the first test target power supply is not erroneously supplied to the first low voltage resistor group RL ₀₁ to the eleventh low voltage resistor group RL ₁₁ not used in the load test. It is desirable to provide a first control device (relay, etc.) 71 that cuts off power supply from the first low-voltage resistor group RL ₀₁ to the eleventh low-voltage resistor group RL ₁₁ .
The first control device 71, if the combined rotational position of the mode switch 61 to the first rotational position P1, regardless of the operating state of the first low-pressure operation switch L _{01 ~} 11 low-pressure operation switch H _11, the The first low voltage relay SL ₀₁ to the eleventh low voltage relay SL ₁₁ are turned off.
The first control device 71 may be provided in the vicinity of the operation unit 60, or may be incorporated in the operation unit 60, or may be provided in another part.

When the rotation position of the mode switch 61 is set to the second rotation position P2, that is, when the load test apparatus 1 is set to the second use mode in which the load test of the second test target power source is performed, the second protection circuit 20b The circuit breaker for wiring is turned on (a state in which power from the second test target power source connected to the second input unit 10b is supplied to the second resistance unit 50b and the like), and the first resistance unit 50a and the second resistance cooling fan unit 50b is driven, based on the operation state of the 21 high-pressure operating switches _{H 21} ~ 24 and high pressure operation switch _{H 24} operation for the first low-pressure switch _{L 01} ~ 15 low-pressure operation switch _{L 15,} 21 high-voltage resistor group _{RH 21} ~ 24 high-voltage resistor group _{RH 24} of each of the first 21 pressure relay _{SH 21} ~ 24 pressure relay _{SH 24,} and the first low-pressure resistance On / off control of the first low-voltage relay SL ₀₁ to the fifteenth low-voltage relay SL ₁₅ of each of the resistor group RL ₀₁ to the fifteenth low-voltage resistor group RL ₁₅ is performed (see FIG. 6).
FIG. 6 shows, in bold lines, power lines from the second test target power supply to the resistor group that can be supplied with power.

In this case, the second test target power supply is used so that the first test high-voltage resistor group RH ₀₁ to the twentieth high-voltage resistor group RH ₂₀ not used in the load test are not erroneously supplied with power from the second test target power supply. It is desirable that a second control device (relay, etc.) 72 for cutting off the power supply from the first high voltage resistor group RH ₀₁ to the twentieth high voltage resistor group RH ₂₀ is provided.
The second control device 72, if the combined rotational position of the mode switch 61 to the second rotational position P2, regardless the operation state of the first high-pressure operation switch H _{01 ~} # 20 high-pressure operating switch H _20, the The first high voltage relay SH ₀₁ to the twentieth high voltage relay SH ₂₀ are turned off.
The second control device 72 may be provided in the vicinity of the operation unit 60 or incorporated in the operation unit 60, or may be provided in another part.

When the rotation position of the mode switch 61 is set to the third rotation position P3, that is, when the load test apparatus 1 is set to the third use mode for performing the load test of the third test target power source, the second protection circuit 20b The circuit breaker for wiring is turned on (a state in which power from the third test target power source connected to the second input unit 10b is supplied to the second resistance unit 50b), and the cooling fan of the second resistance unit 50b is driven. Based on the operating state of the first low pressure operation switch L ₀₁ to the fifteenth low pressure operation switch L ₁₅ , the first low pressure resistor group RL ₀₁ to the fifteenth low pressure resistor group RL ₁₅ respectively. The on / off control of the relay SL ₀₁ to the 15th low pressure relay SL ₁₅ is performed (see FIG. 7).
FIG. 7 shows a power line from the third test target power source to the resistor group that can be powered by a bold line.

The second control device 72, if the combined rotational position of the mode switch 61 to the third rotational position P3, regardless of the operating state of the first high-pressure operation switch H _{01 ~} 24 for high pressure operation switch H _24, the It is desirable to turn off the first high-voltage relay SH ₀₁ to the 24th high-voltage relay SH ₂₄ .

  Therefore, in the load test of the first test target power source connected to the first input unit 10a, when applying the maximum load, the first resistor is not boosted or stepped down from the first test target power source. Power is supplied to the resistor group constituting the unit 50a, and power is supplied to a part or all of the resistor group constituting the second resistor unit 50b in a state where the voltage is stepped down by the bidirectional transformer 40.

  Further, in the load test of the second test target power source connected to the second input unit 10b, when applying the maximum load, the second test target power source is boosted by the bidirectional transformer 40 in the second boosted state. Electric power is supplied to a part of the resistor group constituting the one resistance unit 50a, and electric power is supplied to the resistor group constituting the second resistance unit 50b in a state where neither boosting nor stepping down is performed.

  Further, in the load test of the third test target power source connected to the second input unit 10b, when the maximum load is applied, the second resistance is set from the second test target power source without being stepped up or stepped down. Power is supplied to the resistor group constituting the unit 50b.

  When the rotational position of the mode switch 61 is set to the fourth rotational position P4, the vacuum circuit breaker of the first protection circuit 20a and the wiring circuit breaker of the second protection circuit 20b are turned off.

When performing a high-voltage load test, not only the resistor group of the first resistor unit 50a but also the bidirectional transformer 40 is used for the purpose of step-down, and the low-voltage second and third test target power supplies are mainly used. Since a part or all of the resistor group of the second resistance unit 50b for use in the load test is used, it is possible to perform a load test with a large load compared to a configuration in which the second resistance unit 50b is not used. Become.
When performing a low-voltage load test, not only the resistor group of the second resistance unit 50b but also the bidirectional transformer 40 is used for boosting purposes, and is mainly used for the load test of the high-voltage first test target power source. Since a part of the resistor group of the first resistor unit 50a is also used, it is possible to perform a load test with a large load compared to a configuration in which the first resistor unit 50a is not used.

  In addition, the resistor group (load) that applies the boosted voltage and the resistor group (load) that applies the stepped-down voltage are part of the resistor group that performs the load test, so all the resistor groups Compared with a mode in which a voltage in a boosted state is applied to a voltage and a mode in which a voltage in a voltage-down state is applied to all resistor groups, a transformer having a smaller rated capacity (bidirectional transformer 40) is used. It becomes possible to use.

  In addition, since the bidirectional transformer 40 serves as both a step-up transformer and a step-down transformer, the low-voltage resistance unit (second output) is used during a high-voltage load test (in the first test mode). The resistance unit 50b) is used to minimize the size of the transformer when using the high voltage resistance unit (first resistance unit 50a) during the low voltage load test (in the second test mode). It becomes possible to do.

  Further, a part of the resistor group of the resistance unit (first resistance unit 50a) mainly used for the load test of the high-voltage test target power source is used as the load test resistor group of the low-voltage test target power source. A part or all of the resistor group of the resistor unit (second resistor unit 50b) used for the load test of the test target power source is used as the load test resistor group of the high voltage test target power source, and at least a part of the resistor group is used. Since the load test resistor group of the high-voltage test target power supply and the low-voltage test target power supply is shared, the material cost of the shared resistor group can be reduced.

  Since the material cost of the shared resistor group can be reduced, even if it is considered that the material cost has increased due to the addition of the bidirectional transformer 40, at least a part of the resistor group is not shared. Compared to the case where the load test device used for the load test of the power supply to be tested and the load test device used for the load test of the low-voltage test power supply are configured separately, the material cost of the load test device as a whole can be reduced. become.

The second control device 72 detects that the wiring breaker of the second protection circuit 20b is turned on, or detects power supply from the wiring breaker to the second resistance unit 50b (for example, Resistor group (first high voltage resistor group RH ₀₁ to 20th high voltage resistor) that is not used even when the maximum load is applied in the load test of the second test target power source or the third test target power source when the voltage is detected. Switches (first high-voltage disconnecting relay X ₀₁ to 20th high-voltage disconnecting relay X ₂₀ ) for turning off the first high-voltage relay SH ₀₁ to the 20th high-voltage relay SH ₂₀ corresponding to the instrument group RH ₂₀ ). The form provided in 1 resistance unit 50a etc. may be sufficient (refer FIG. 8, FIG. 9).

Further, as the first control device 71, it is detected that the vacuum circuit breaker of the first protection circuit 20a is turned on, or power supply detection from the vacuum circuit breaker to the first resistance unit 50a (for example, voltage detection) ) Corresponds to a resistor group (first low-voltage resistor group RL ₀₁ to eleventh low-voltage resistor group RL ₁₁ ) that is not used even when a maximum load is applied in the load test of the first test target power source. Switches (first low-voltage cutoff relay Y ₀₁ to eleventh low-voltage cutoff relay Y ₁₁ ) that turn off the first low-voltage relay SL ₀₁ to the eleventh low-voltage relay SL ₁₁ are provided in the second resistance unit 50 b and the like. A form may be sufficient (refer FIG. 8, FIG. 10).

  The rated capacity of the resistor group, the rated voltage of the power source to be tested, the number of resistor groups, the number of resistor groups used in the low-voltage load test in the first resistor unit 50a, and the high-voltage load test in the second resistor unit 50b The number of resistor groups used in is an example, and other numerical values may be used.

DESCRIPTION OF SYMBOLS 1 Load test apparatus 10a 1st input part 10b 2nd input part 20a 1st protection circuit 20b 2nd protection circuit 30 Interlock circuit 40 Bidirectional transformer 50a 1st resistance unit 50b 2nd resistance unit 60 Operation part 61 Mode switch 71 First control device 72 Second control device H _{01 to} H ₂₄ First high pressure operation switch to 24th high pressure operation switch L _{10 to} L ₁₅ First low pressure operation switch to 15th low pressure operation switch RH _{01 to} RH ₂₄ First high voltage resistor group to 24th high voltage resistor group RL _{01 to} RL ₁₅ First low voltage resistor group to 15th low voltage resistor group SH _{01 to} SH ₂₄ First high voltage relay to 24th high voltage relay SL ₀₁ to SL ₁₅ first low pressure relay to 15th low relay X ₀₁ to X ₂₀ first high-pressure shut-off relay to 20th high-pressure shut-off relay ₀₁ to Y ₁₁ first low-pressure cut-off relay to 11 low-pressure shut-off relay

Claims (8)

A first input unit connected to a first test target power supply;
A second input unit connected to a second test target power source having a smaller rated voltage than the first test target power source;
A first resistance unit provided with a plurality of resistor groups each having one or more resistors;
A plurality of resistor groups having one or more resistors, a second resistor unit having a smaller rated capacity than the first resistor unit;
Both the voltage of the power supplied from the first test target power supply is stepped down via the first input unit, and the voltage of the power supplied from the second test target power supply is boosted via the second input unit. And is used to perform a load test while adjusting the load amount by changing the number of resistor groups to which voltage is applied among the resistor groups in the first resistor unit and the second resistor unit. A load testing device,
In the load test of the first test target power source connected to the first input unit, when applying the maximum load, the first test target power source is not boosted or stepped down. Power is supplied to the resistance unit, and power is supplied to a part or all of the resistor group constituting the second resistance unit in a state where the voltage is stepped down by the bidirectional transformer,
In the load test of the second test target power source connected to the second input unit, when applying the maximum load, the second test target power source is boosted by the bidirectional transformer, A load testing apparatus, wherein power is supplied to a part of the resistor group constituting the first resistance unit, and power is supplied to the second resistance unit in a state where neither boosting nor stepping down is performed. A first circuit breaker that performs on / off control of power supply from the first power source to be tested to the first resistance unit and the bidirectional transformer via the first input unit;
A second circuit breaker that performs on / off control of power supply from the second test target power source to the second resistance unit and the bidirectional transformer via the second input unit;
When power is being supplied from the first test target power source to the first resistance unit and the bidirectional transformer via the first input unit, the second circuit breaker is turned off,
An interlock that turns off the first circuit breaker when power is supplied from the second test target power source to the second resistance unit and the bidirectional transformer via the second input unit. The load test apparatus according to claim 1, further comprising a circuit.   When power is supplied from the first power source to be tested to the first resistance unit and the bidirectional transformer via the first input unit, the first resistance unit and the second resistance unit are connected to each other. Regardless of the operation state of the operation switch for selecting a resistor group to be used for the load test from among the resistor groups to be configured, among the resistor groups that constitute the second resistor unit, Even when a maximum load is applied in the load test, the power supply to the resistor group that is not used is cut off, and from the second test target power source to the second resistance unit or the bidirectional transformer via the second input unit. When the power supply is performed, regardless of the operation state of the operation switch, the maximum load is applied in the load test of the second test target power source among the resistor groups constituting the first resistance unit. In case Load test apparatus according to claim 1, further comprising a control device for interrupting the power supply to not use resistor group.   2. The load test apparatus according to claim 1, wherein a rated voltage of the second test target power source is 1/5 or less of a rated voltage of the first test target power source.   2. The load test apparatus according to claim 1, wherein a rated capacity of the second resistance unit is 1/3 or less of a rated capacity of the first resistance unit.   Among the resistor groups that constitute the first resistor unit, the rated capacity of the resistor group that constitutes the second resistor unit is smaller than the rated capacity of the resistor group that constitutes the second resistor unit. The load test apparatus according to claim 5. Used to select the operation switch for selecting the resistor group used for the load test from among the resistor groups constituting the first resistor unit and the second resistor unit, and the type of the power source to be tested. An operation unit having a mode switch;
When the mode switch is set to a first use mode for performing a load test of the first power source to be tested via the first input unit, the second resistance is set regardless of an operation state of the operation switch. The power supply to the resistor group not used in the first use mode among the resistor groups constituting the unit is cut off, and the mode switch is connected to the second test target power supply via the second input unit. Resistor group not used in the second usage mode among the resistor groups constituting the first resistance unit regardless of the operation state of the operation switch when set to the second usage mode for performing a load test The load test apparatus according to claim 1, further comprising a control device that cuts off power supply to the power supply. Of the resistor group constituting the second resistance unit, the rated capacity of the first test target power supply used for the load test is not more than three-quarters of the capacity of the first test target power supply. The load test apparatus according to claim 1, wherein

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