CN217183183U - Constant current source device for temperature rise test of alternating current and direct current complete switch cabinet - Google Patents
Constant current source device for temperature rise test of alternating current and direct current complete switch cabinet Download PDFInfo
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- CN217183183U CN217183183U CN202122992704.XU CN202122992704U CN217183183U CN 217183183 U CN217183183 U CN 217183183U CN 202122992704 U CN202122992704 U CN 202122992704U CN 217183183 U CN217183183 U CN 217183183U
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Abstract
The utility model discloses a constant current source device for AC/DC complete switch cabinet temperature rise test, which comprises a slow start circuit, an input isolation transformer, a rectifier, a power electronic power converter, a filtering and AC/DC output switching control unit which are connected in sequence; the constant current source device also comprises a control module, if the control module is configured to be in an alternating current mode, the power electronic power converter is configured to convert direct current into alternating current, and the filtering and alternating current-direct current output switching control unit is configured to filter alternating current signals so as to enable the adaptive output end to be connected with the alternating current complete switch cabinet; if the control module is configured to be in a direct current mode, the power electronic power converter is configured to convert direct current into direct current, and the filtering and alternating current-direct current output switching control unit is configured to filter direct current signals to adapt the output end to be connected with the direct current complete switch cabinet. The utility model discloses a constant current source device can satisfy simultaneously and exchange complete set switchgear and direct current complete set switchgear's test demand.
Description
Technical Field
The utility model relates to a temperature rise test technical field especially relates to a constant current source device for exchanging direct current complete set cubical switchboard temperature rise test.
Background
The temperature rise generated in the running process of the alternating-current complete set of switch equipment and the direct-current complete set of switch equipment has direct influence on the safety and reliability of the switch equipment and a power supply system, so that the temperature rise tests in national standards GB7251-2013 and GB25890 are vital test items of the switch equipment. According to the standard temperature rise test, the whole set of equipment is involved, and the temperature rise of each function, the main bus and the distribution bus is involved.
The existing alternating current heavy current generating device for temperature rise test of the complete set of switch equipment generally adopts a multi-magnetic circuit transformer to convert commercial power into an output power supply of low-voltage heavy current, the output power supply is connected to the input end of the low-voltage complete set of switch equipment, and a variable resistor or a current regulator is connected to each branch feeder of tested equipment to be used as an adjustable load to obtain adjustable test current for temperature rise test.
Because the whole system is large in size, the test current can also change due to the voltage fluctuation of a power grid and the resistance change of related elements in a current-carrying loop, the adjustment intervention of an operator is often required, the adjustment precision of the output current is generally more than 3%, and meanwhile, the problem that the inductive reactive power of an input end is too large is caused, the quality of the power grid is influenced, and the energy waste is caused.
Theoretically, the higher the output current precision and the better the stability of the current generating device for supplying current to the switchgear assembly, the more accurate the test result of the temperature rise test of the switchgear assembly is.
The prior art lacks an ideal high-precision and high-stability current generating device for the temperature rise test of complete set of switch equipment.
SUMMERY OF THE UTILITY MODEL
In order to solve the problem of the prior art, the utility model provides a constant current source device for exchanging direct current complete set cubical switchboard temperature rise test, not only output current precision is high, stability is good, can also dispose the test demand of alternating current mode and direct current mode in order to satisfy the different grade type in a flexible way, technical scheme as follows:
the utility model provides a constant current source device for exchanging direct current complete set cubical switchboard temperature rise test for exchanging complete set cubical switchboard and/or direct current complete set cubical switchboard provide the electric current for the temperature rise test, constant current source device includes that the order is connected:
the input end of the slow starting circuit is electrically connected with an alternating current power supply outside the device through a connector;
the input side of the input isolation transformer is electrically connected with the output side of the slow start circuit so as to convert the input voltage and output the converted voltage, and the input side and the output side of the input isolation transformer are isolated from each other;
the number of the constant current branches is more than three, the input end of each constant current branch is connected with the output side of the input isolation transformer, and the output end of each constant current branch is configured to be connected with the complete switch cabinet; each constant current branch comprises:
a rectifier, an input end of which is connected with an output side of the input isolation transformer, and which is configured to convert the received alternating current into direct current;
a power electronic power converter, an input of which is connected with an output of the rectifier, configured to perform power conversion;
a filtering and AC/DC output switching control unit, the input end of which is connected with the output end of the power electronic power converter, and the filtering and AC/DC output switching control unit is configured to filter the received signals;
the constant current source device further comprises a control module, the control module is electrically connected with the power electronic power converter and the filtering and alternating current/direct current output switching control unit, the control module is configured to control the working states of the power electronic power converter and the filtering and alternating current/direct current output switching control unit, and the control module comprises:
if the control module is configured to be in an alternating current mode, selecting a DC/AC converter access circuit and selecting an alternating current filter access circuit;
if the control module is configured to be in a direct current mode, the DC/DC converter access circuit is selected, and the direct current filter access circuit is selected.
Further, the power electronic power converter includes a power switch device, and the control module is configured to set a target current and perform closed-loop PI control according to a set value of the target current, and includes: calculating and outputting a PWM wave to control the on-off or opening of a power switch device of the power electronic power converter;
the control module is configured to independently control the output current of the output end of each constant current branch, and compared with the set value of the target current, the current error rate of the current output after the filtering and the alternating current-direct current output switching control unit is less than 2%.
Further, the power switch device is an IGBT or a MOSFET, and a current error rate of the current output after the filtering and the filtering of the ac/dc output switching control unit is less than 1% compared with a set value of the target current.
Further, the constant current source device is provided with a key or a man-machine interaction button which is configured to select a DC/AC converter or a DC/DC converter access circuit and select an alternating current filter or a direct current filter access circuit.
Further, when the output end of the constant current branch circuit is connected with an alternating current complete switch cabinet, the control module is configured to select a three-phase output mode or a single-phase output mode;
if the control module selects a three-phase output mode, the output ends of the three constant-current branches are respectively an output end live wire, an output end zero line and an output end ground wire, wherein the output end ground wire is grounded, the output end live wire is connected with one output three-phase live wire phase end of the AC complete switch cabinet, the output end zero line is in short circuit with an input three-phase live wire short contact of the AC complete switch cabinet, or the output ends of the constant-current branches are connected in parallel with one output distribution bus;
if the control module selects a single-phase output mode, the output end of a single constant-current branch circuit is connected with the output end of the AC complete switch cabinet, or the output ends of a plurality of constant-current branch circuits are connected in parallel with the output end of the AC complete switch cabinet.
Further, when the output ends of the constant current branches are connected with a direct current complete set of switch cabinet, the control module is configured in a direct current mode, the output ends of the constant current branches are respectively connected with the output ends of the direct current complete set of switch cabinet, or the output ends of the constant current branches are connected in parallel with the output ends of the direct current complete set of switch cabinet.
Further, a single set of constant current source devices is configured with six or eight or nine constant current branches.
Further, sets of constant current source devices are configured to be operable in parallel to provide output current to a set of switchgear.
Furthermore, the input end of the slow start circuit is connected with an alternating current commercial power, and the power output end of the constant current branch is configured with an output terminal or a copper bar.
Further, the control module comprises a main control unit and a power conversion control interface unit which are electrically connected with each other, wherein,
the power conversion control interface unit is electrically connected with the power electronic power converters of the constant-current branches and is configured to control the working states of the power electronic power converters to convert direct current into alternating current or convert direct current into direct current;
the main control unit is electrically connected with the filtering and alternating current/direct current output switching control unit of each constant current branch, and is configured to control the working state of the filtering and alternating current/direct current output switching control unit to be filtering of alternating current signals or filtering of direct current signals.
Further, the control module further comprises a measurement unit and a human-machine interface, wherein,
the measuring unit is electrically connected with the main control unit and is configured to sample the output current and/or the output voltage of each constant current branch circuit;
the human-computer interface is electrically connected with the main control unit through the communication unit and is configured to display test data of the temperature rise test of the switch cabinet set.
The utility model provides a beneficial effect that technical scheme brought as follows:
a. the testing requirements of alternating current complete set of switch equipment and direct current complete set of switch equipment can be met simultaneously by using a set of alternating current and direct current dual-purpose constant current source device, and the configuration cost of the complete set of switch cabinet testing device is reduced;
b. the constant current source device adopting the power electronic power converter has high output current precision and good stability, and improves the test result precision of the temperature rise test of the complete set of switch equipment.
Drawings
In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments described in the present application, and other drawings can be obtained by those skilled in the art without creative efforts.
Fig. 1 is a schematic circuit structure diagram of a constant current source device for temperature rise test of an ac/dc switchgear assembly according to an exemplary embodiment of the present disclosure.
Detailed Description
In order to make the technical solution of the present invention better understood, the technical solution of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts shall belong to the protection scope of the present invention.
It is noted that the terms "comprises" and "comprising," and any variations thereof, in the description and claims of the present invention, are intended to cover a non-exclusive inclusion, such that a process, method, apparatus, product, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, product, or apparatus.
In the prior art, two different test systems are required to be configured for test occasions of an alternating current complete set of switch equipment and a direct current complete set of switch equipment, and a current generator is configured for each test system. The utility model discloses an one of them design lies in providing a constant current source device that configuration flexibility ratio is high, can satisfy the test demand of exchanging complete set switchgear and direct current complete set switchgear simultaneously, exchanges or the direct current to the complete sets output that is temperature rise test in the occasion that the output accuracy requires height.
The utility model discloses an in an embodiment, provide a constant current source device for exchanging direct current complete set cubical switchboard temperature rise test for exchange complete set cubical switchboard and/or direct current complete set cubical switchboard provide the test of temperature rise and use electric current, the constant current source device of this embodiment can satisfy the test demand of exchanging complete set switchgear and direct current complete set switchgear simultaneously, as shown in FIG. 1, the constant current source device includes the following circuit module of sequential connection:
the input end of the slow start circuit is electrically connected with an alternating current power supply (such as 220V alternating current commercial power) outside the device through a connector, so that the output voltage of the slow start circuit slowly rises when the connector is connected with the external alternating current power supply; the slow start circuit is used to reduce the impact of the impulse current on the circuit, and the common methods include series connection of inductors, series connection of resistors, series connection of NTC resistors, and the like.
The input side of the input isolation transformer is electrically connected with the output side of the slow start circuit so as to convert the input voltage and output the converted voltage, and the input side and the output side of the input isolation transformer are isolated from each other;
the number of the constant current branches is more than three, the input end of each constant current branch is connected with the output side of the input isolation transformer, and the power output end of each constant current branch is configured with an output terminal or a copper bar for connecting a complete set of switch cabinet; each constant current branch comprises:
a rectifier having an input connected to the output side of the input isolation transformer and configured to convert the received AC power to DC power.
A power electronic power converter, an input of which is connected with an output of the rectifier, configured to perform power conversion; in particular, the power electronic power converter comprises power switching devices, such as IGBTs or MOSFETs, and the power electronic power converter comprises a DC/DC converter and a DC/AC converter.
The input end of the filtering and alternating current/direct current output switching control unit is connected with the output end of the power electronic power converter, the filtering and alternating current/direct current output switching control unit is configured to filter received signals, and the output end of the filtering and alternating current/direct current output switching control unit is connected with the tested switch cabinet equipment through an output terminal or a busbar; specifically, the filtering and alternating current/direct current output switching control unit comprises a direct current filter and an alternating current filter.
The above are the main components of the current generator, and when the DC/DC converter and the DC filter access circuit are selected, the DC current generator is formed, and when the DC/AC converter and the AC filter access circuit are selected, the AC current generator is formed.
The constant current source device further comprises a control module, the control module is electrically connected with the power electronic power converter, the filter and the alternating current/direct current output switching control unit, the control module is configured to control the working states of the power electronic power converter, the filter and the alternating current/direct current output switching control unit, a reverse power transmission mode is adopted during testing, namely, the output current of the constant current source is accessed from the power distribution output end of the switch cabinet, the short circuit is realized at the main bus input end of the switch cabinet, and:
if the control module is configured in an alternating current mode, selecting a DC/AC converter access circuit to enable the working state of the converter to convert direct current into alternating current, and selecting an alternating current filter access circuit to enable the working state of the filtering and alternating current/direct current output switching control unit to filter alternating current signals so as to adapt to the output end to be connected with an alternating current complete switch cabinet;
if the control module is configured in a direct current mode, the DC/DC converter access circuit is selected, the working state of the converter is to convert direct current into direct current, and the direct current filter access circuit is selected, so that the working state of the filtering and alternating current/direct current output switching control unit is to filter direct current signals, and the filtering and alternating current/direct current output switching control unit is adapted to the output end to be connected with a direct current complete switch cabinet.
The following description is made for the applicable modes of different types of complete switch cabinets respectively:
when the output end is connected with an alternating-current complete set switch cabinet, the control module is configured to select a three-phase output mode or a single-phase output mode;
if the control module selects a three-phase output mode, the output ends of the three constant-current branches are respectively an output end live wire, an output end zero line and an output end ground wire, wherein the output end ground wire is grounded, the output end live wire is connected with one output three-phase live wire phase end of the alternating-current complete switch cabinet, the output end zero line is in short circuit with an input three-phase live wire short contact of the alternating-current complete switch cabinet, three phases are different by 120 degrees in phase, or the output ends of the constant-current branches are connected in parallel with one output distribution bus;
if the control module selects a single-phase output mode, the output end of a single constant current branch is connected with the output end of the AC complete set switch cabinet, or the output ends of a plurality of constant current branches are connected in parallel with the output end of the AC complete set switch cabinet.
When the output end is connected with a direct current complete set switch cabinet, the control module is configured to be in a direct current mode, the output end of each constant current branch is respectively connected with the output end of the direct current complete set switch cabinet, or the output ends of a plurality of constant current branches are connected in parallel to the output end of the direct current complete set switch cabinet.
The control module is configured to set a target current, and after the mode is set, the control module performs closed-loop PI control according to a set value of the target current, and the control module comprises: calculating and outputting a PWM wave to control the on-off or opening size of a power switch element of the power electronic power converter; the control module is configured to independently control the output current of the output end of each constant current branch, high precision and high stability of the output current of the constant current source device are achieved through closed-loop PI control automatic adjustment, compared with the set value of the target current, the current output after filtering by the filtering and alternating current-direct current output switching control unit has a current error rate smaller than 1% of that of a single-path or a summary main bus, namely the absolute value of the difference between the actual output current and the set value of the target current is smaller than 1% of that of the target current, and the influence caused by mains supply fluctuation, component impedance change in a switch cabinet and wiring form change in the switch cabinet is avoided, so that the flexibility and the high efficiency of the temperature rise test process are enhanced.
In the present embodiment, a power electronic power converter is adopted, the current stabilization precision is high, the dynamic response is fast, and multiple paths of outputs can be flexibly performed, taking the example that the single set of constant current source device illustrated in fig. 1 is configured with six constant current branches, since each constant current branch can be independently controlled, for example, three terminals "output 1" - "output 3" in fig. 1 can be connected to a three-phase ac complete set switch cabinet, and terminals "output 4", "output 5" and "output 6" in fig. 1 can be connected to a single-phase output of the ac complete set switch cabinet in parallel, and can also be configured to be 6-path single-phase output or 2-path three-phase output, which is flexibly configured, and no secondary connection is needed.
When the parallel output current of all constant current branches of one set of constant current source device cannot meet the requirement of one large-capacity switch cabinet, a plurality of sets of constant current source devices can be operated in parallel to provide output current for one set of switch cabinet, the current output capability during testing is further enhanced, and the flexibility of configuration of the testing device is improved.
As shown in fig. 1, the control module includes a main control unit, and a power conversion control interface unit, a measurement unit, and a communication unit electrically connected to the main control unit, where the communication unit is used to connect a human-machine interface, such as an HMI human-machine interface.
The power conversion control interface unit is electrically connected with the converters of the constant current branches and is configured to send instructions to the converters so as to control the working states of the converters to convert direct current into alternating current or convert direct current into direct current;
the main control unit is electrically connected with the filtering and alternating current/direct current output switching control unit of each constant current branch, and is configured to send an instruction to the main control unit so as to control the working state of the filtering and alternating current/direct current output switching control unit to be filtering of alternating current signals or filtering of direct current signals.
The measuring unit is electrically connected with the main control unit and is configured to sample the output current and/or the output voltage of each constant current branch circuit;
the human-computer interface is electrically connected with the main control unit through the communication unit and is configured to display test data of the temperature rise test of the switch cabinet set.
In this embodiment, the control module may set the operating states of the power electronic power converter and the filtering and ac/dc output switching control unit manually, for example, a control button may be set on the device, or a control button may be set on a human-computer interface to set the ac mode or the dc mode manually. For example, the constant current source device is provided with a key or a man-machine interaction button configured to select a DC/AC converter or a DC/DC converter access circuit, and select an AC filter or a DC filter access circuit.
If an alternating current mode key is pressed down or an alternating current mode button is clicked, the power electronic power converter works in a DC/AC working mode, and the alternating current filter is connected to the circuit; and if the direct current mode key is pressed/the direct current mode button is clicked, the power electronic power converter works in a DC/DC working mode, and the direct current filter is connected into the circuit. The method is just like operating the air volume grade button on the electric fan, different output power modes of the motor of the electric fan can be controlled, and the mode control can be realized through a circuit without improving a computer program.
It should be noted that, in this document, terms such as "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
The foregoing is illustrative of the present disclosure and it will be appreciated by those skilled in the art that changes may be made in this embodiment without departing from the principles of the disclosure, the scope of which is defined by the appended claims.
Claims (10)
1. The utility model provides a constant current source device for exchanging direct current complete set cubical switchboard temperature rise test which characterized in that for exchanging complete set cubical switchboard and direct current complete set cubical switchboard provide the test of temperature rise and use electric current, constant current source device includes that the order is connected:
the input end of the slow starting circuit is electrically connected with an alternating current power supply outside the device through a connector;
the input side of the input isolation transformer is electrically connected with the output side of the slow start circuit so as to convert the input voltage and output the converted voltage, and the input side and the output side of the input isolation transformer are isolated from each other;
the number of the constant current branches is more than three, the input end of each constant current branch is connected with the output side of the input isolation transformer, and the output end of each constant current branch is configured to be connected with the complete switch cabinet; each constant current branch comprises:
a rectifier, an input end of which is connected with an output side of the input isolation transformer, and which is configured to convert the received alternating current into direct current;
a power electronic power converter, an input of which is connected with an output of the rectifier, configured to perform power conversion;
a filtering and alternating current-direct current output switching control unit, the input end of which is connected with the output end of the power electronic power converter, and the filtering and alternating current-direct current output switching control unit is configured to filter the received signals;
the constant current source device further comprises a control module, the control module is electrically connected with the power electronic power converter and the filtering and alternating current/direct current output switching control unit, the control module is configured to control the working states of the power electronic power converter and the filtering and alternating current/direct current output switching control unit, and the control module comprises:
if the control module is configured to be in an alternating current mode, selecting a DC/AC converter access circuit and selecting an alternating current filter access circuit;
if the control module is configured to be in a direct current mode, the DC/DC converter access circuit is selected, and the direct current filter access circuit is selected.
2. The constant current source arrangement according to claim 1, wherein the power electronic power converter comprises a power switching device, the power switching device being an IGBT or a MOSFET.
3. The constant current source device according to claim 1, wherein the constant current source device is provided with a button or a man-machine interaction button configured to select a DC/AC converter or a DC/DC converter access circuit and select an AC filter or a DC filter access circuit.
4. The constant current source device according to claim 1, wherein when the output terminal of the constant current branch is connected to an ac switchgear assembly, the control module is configured to select a three-phase output mode or a single-phase output mode;
if the control module selects a three-phase output mode, the output ends of the three constant-current branches are respectively an output end live wire, an output end zero line and an output end ground wire, wherein the output end ground wire is grounded, the output end live wire is connected with one output three-phase live wire phase end of the AC complete switch cabinet, the output end zero line is in short circuit with an input three-phase live wire short contact of the AC complete switch cabinet, or the output ends of the constant-current branches are connected in parallel with one output distribution bus;
if the control module selects a single-phase output mode, the output end of a single constant current branch is connected with the output end of the AC complete set switch cabinet, or the output ends of a plurality of constant current branches are connected in parallel with the output end of the AC complete set switch cabinet.
5. The constant current source device according to claim 1, wherein when the output terminals of the constant current branches are connected to a dc complete set of switch cabinets, the control module is configured to be in a dc mode, and the output terminals of each constant current branch are respectively connected to the output terminals of the dc complete set of switch cabinets, or the output terminals of a plurality of constant current branches are connected in parallel to the output terminals of the dc complete set of switch cabinets.
6. The constant current source device according to claim 1, wherein a single set of constant current source devices is configured with six or eight or nine constant current branches.
7. The constant current source device of claim 1, wherein sets of constant current source devices are configured to be operable in parallel to provide output current to a set of switch cabinets.
8. The constant current source device according to claim 1, wherein an input end of the slow start circuit is connected to an alternating current commercial power, and a power output end of the constant current branch is configured with an output terminal or a copper bar.
9. The constant current source device according to claim 1, wherein the control module comprises a main control unit and a power conversion control interface unit electrically connected to each other,
the power conversion control interface unit is electrically connected with the power electronic power converters of the constant-current branches and is configured to control the working states of the power electronic power converters to convert direct current into alternating current or convert direct current into direct current;
the main control unit is electrically connected with the filtering and alternating current/direct current output switching control unit of each constant current branch, and is configured to control the working state of the filtering and alternating current/direct current output switching control unit to be filtering of alternating current signals or filtering of direct current signals.
10. The constant current source device according to claim 9, wherein the control module further comprises a measurement unit and a human-machine interface, wherein,
the measuring unit is electrically connected with the main control unit and is configured to sample the output current and/or the output voltage of each constant current branch circuit;
the human-computer interface is electrically connected with the main control unit through the communication unit and is configured to display test data of the temperature rise test of the switch cabinet set.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202122992704.XU CN217183183U (en) | 2021-11-30 | 2021-11-30 | Constant current source device for temperature rise test of alternating current and direct current complete switch cabinet |
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| CN202122992704.XU CN217183183U (en) | 2021-11-30 | 2021-11-30 | Constant current source device for temperature rise test of alternating current and direct current complete switch cabinet |
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