CN111865102A - Electronic type analog load system - Google Patents
Electronic type analog load system Download PDFInfo
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- CN111865102A CN111865102A CN202010742172.1A CN202010742172A CN111865102A CN 111865102 A CN111865102 A CN 111865102A CN 202010742172 A CN202010742172 A CN 202010742172A CN 111865102 A CN111865102 A CN 111865102A
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- 238000004088 simulation Methods 0.000 claims abstract description 15
- 239000003990 capacitor Substances 0.000 claims description 54
- 230000000087 stabilizing effect Effects 0.000 claims description 7
- 238000001514 detection method Methods 0.000 claims description 3
- 230000003068 static effect Effects 0.000 abstract description 3
- 229910000831 Steel Inorganic materials 0.000 abstract description 2
- 238000012545 processing Methods 0.000 abstract description 2
- 239000010959 steel Substances 0.000 abstract description 2
- 230000006698 induction Effects 0.000 abstract 1
- 238000012360 testing method Methods 0.000 description 4
- 238000002474 experimental method Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 230000004044 response Effects 0.000 description 2
- 230000008859 change Effects 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 230000017525 heat dissipation Effects 0.000 description 1
- 230000001939 inductive effect Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M5/00—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases
- H02M5/40—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc
- H02M5/42—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters
- H02M5/44—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters using discharge tubes or semiconductor devices to convert the intermediate dc into ac
- H02M5/453—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters using discharge tubes or semiconductor devices to convert the intermediate dc into ac using devices of a triode or transistor type requiring continuous application of a control signal
- H02M5/458—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters using discharge tubes or semiconductor devices to convert the intermediate dc into ac using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only
- H02M5/4585—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters using discharge tubes or semiconductor devices to convert the intermediate dc into ac using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only having a rectifier with controlled elements
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Abstract
The invention discloses an electronic load simulation system which comprises two three-phase pulse width modulation current converter systems, wherein each three-phase pulse width modulation current converter system comprises an inversion or induction unit component, a sensor component, a power unit component, a control unit component, a filter unit component, a transformer unit component, an alternating current port component and a direct current port component; the two devices operate back to back, can simulate electronic loads, can simulate common load models in a low-voltage power grid, such as steel industrial loads, food industrial loads, rural processing loads and municipal and domestic electric loads, operate according to active power daily load curves of the load models, can simulate comprehensive load characteristics of a power system, and can simulate static voltage characteristics of various industrial loads.
Description
Technical Field
The invention relates to the field of electronic loads, in particular to an electronic load simulation system.
Background
The electronic load is characterized in that the rectifier reflects the load characteristic by adjusting the phase lead or lag of voltage and current through a fully-controlled device, the electronic load can be flexibly used as an inductive load or a capacitive load, and the phase size can be adjusted through a touch screen.
The other end of the electronic load is provided with an inverter which can feed the energy of the rectifier back to the power grid.
The electronic load is a novel load adopting power electronic technology, and can output equivalent impedance value and phase angle between voltage and current and simulate resistance, reactance and capacitance volt-ampere characteristics by controlling the conduction flux (duty ratio) of an internal power device (IGBT or MOSFET or SCR) according to the given value. Debugging detection of a general high-power supply is indispensable. However, the traditional loads such as the resistor and the capacitor are all nonadjustable with fixed parameters, in order to meet the test requirements, different resistors and capacitors are usually connected in series and in parallel or combined by adopting adjustable resistors, reactors and capacitors, and the two modes can not flexibly realize the setting of related parameters, even the recombination of the capacitor and the resistor needs to be adjusted by manual wiring in case of power failure. Secondly, the two modes lead to the fact that loads such as resistors consume a large amount of electric energy, increase the electricity consumption cost and increase resistor heat dissipation equipment and fields.
The power supply product experiment needs to be tested under a plurality of different operation states, a plurality of load models can be selected urgently, the power supply product experiment can be operated according to an active power daily load curve of the model, or the comprehensive load characteristic of a power system can be simulated, the static voltage characteristic of a plurality of industrial loads can be simulated, remote control intelligent loads can be realized through communication, the traditional RLC load parameter range is small, the adjustment is inflexible, the energy consumption is large, and the experiment requirements are difficult to meet.
Disclosure of Invention
The invention aims to provide an electronic load simulation system, which is used for solving at least one problem in the prior art, so that electronic load equipment is controllable, the actual loss electric energy is reduced, and a multi-scene load mode can be simulated.
In order to achieve the purpose, the invention provides the following scheme: the invention provides an electronic load simulation system, comprising: a first three-phase pulse width modulation converter system and a second three-phase pulse width modulation converter system;
a three-phase pulse width modulated inverter system comprising: the device comprises an inversion or rectification unit component, a sensor unit component, a power unit component, a control unit component, a filter unit component, a transformer unit component, a direct current port component and an alternating current port component;
the inversion or rectification unit component is connected with the sensor unit component and the controller unit component;
the sensor unit component is connected with the inversion or rectification unit component, the filter unit component and the alternating current port component;
the power unit component is connected with the control unit component and the inversion or rectification unit component;
the control unit assembly is connected with the power unit assembly and the direct current port assembly;
the filter unit component is connected with the inversion or rectification unit component and the transformer unit component;
the transformer unit assembly is connected with the sensor assembly and the alternating current port assembly;
preferably, the inversion or rectification unit component comprises an IGBT group, a first inversion or rectification filter capacitor, a second inversion or rectification filter capacitor and a direct-current voltage-stabilizing capacitor;
preferably, the IGBT group is connected to the first inverter or rectifier filter capacitor, the first inverter or rectifier filter capacitor is connected to the dc voltage stabilizing capacitor, the dc voltage stabilizing capacitor is connected to the second inverter or rectifier filter capacitor, the second inverter or rectifier filter capacitor is connected to the IGBT group, and the IGBT group is connected to the dc power input port;
preferably, the sensor unit assembly comprises a current sensor element, a voltage sensor element and an intelligent three-phase electric parameter meter;
preferably, the current sensor unit element is connected with the inversion or rectification unit component and the digital display ammeter;
preferably, the voltage sensor is connected with the filter unit assembly and the digital display voltmeter;
preferably, the intelligent three-phase electric parameter meter is connected with the current sensor element and the alternating current port assembly;
preferably, the power unit element is a DSP controller, and the DPS controller includes a first DSP chip, a second DSP chip, a third DSP chip, and a fourth DSP chip;
preferably, the control unit assembly comprises a switch unit and a current transformer unit, and is used for signal output and control of the circuit operation condition;
preferably, the current transformer unit is connected with the alternating current output port;
preferably, the control unit assembly further comprises an RLC load unit for performance detection of the electronic analogue load system.
Preferably, the filter unit component comprises a filter capacitor and a reactor;
preferably, the filter capacitance comprises: a first filter capacitor, a second filter capacitor, a third filter capacitor;
preferably, the reactor includes: a first reactor, a second reactor and a third reactor;
preferably, the power supply further comprises a pre-charging module, the pre-charging module pre-charges the dc voltage-stabilizing capacitor C, the main contactor is in an off state, the main circuit is closed and then the main contactor is closed after 3 seconds, so as to bypass the pre-charging resistor, and prevent the power supply from generating a large impact current at the moment of power-on to damage the device;
preferably, the first three-phase pulse width modulation converter system and the second three-phase pulse width modulation converter system are connected through a direct current port;
preferably, the first three-phase pulse width modulation converter system is in a rectification operating mode; the second three-phase pulse width modulation converter system is in an inversion working mode;
the invention discloses the following technical effects:
1. the fully-controlled IGBT power module is adopted, the switching frequency is 10kHz, the size of the filter reactor can be reduced by 50%, the loss is reduced by 10%, the response speed is improved to within 1ms, the output precision reaches 0.5%, and the volt-ampere characteristic and the 24-hour operation curve of the load can be set at will;
2. the device can simulate common load models in a low-voltage power grid, such as steel industrial load, food industrial load, rural processing load and municipal and domestic power load, and operates according to the daily load curve of active power of the load models, and can simulate the comprehensive load characteristic of a power system and simulate the static voltage characteristic of various industrial loads.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without inventive exercise.
FIG. 1 is a diagram of an electronic load system;
FIG. 2 is a circuit diagram of a three-phase pulse width modulated inverter system;
wherein, 1 is the contravariant unit subassembly, 2 is the power unit subassembly, 3 is the control unit subassembly, 4 is the sensor subassembly, 5 is the filter unit subassembly, 6 is the transformer subassembly.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.
The present invention provides an electronic load simulation system, as shown in fig. 1, including: two three-phase pulse width modulation transverter systems, the direct current port of two three-phase pulse width modulation transverter systems links to each other, and two three-phase pulse width modulation transverter systems operate rectification mode and contravariant mode respectively, specific control flow: after a test power supply (test article) is connected with an electronic load, the load size, the phase and the change curve are set, the test power supply is started, input alternating current is rectified by a rectifier of the electronic load to output direct current voltage of 500V, the alternating current is inverted into three-phase alternating current by high frequency of an inverter of the electronic load, and the three-phase alternating current is isolated by LC filtering and a transformer, and energy is fed back to a power grid.
As shown in fig. 2, the three-phase pwm converter system includes an inverter or rectifier unit assembly, a sensor unit assembly, a power unit assembly, a control unit assembly, a filter unit assembly, and a transformer unit assembly;
the inversion or rectification unit component comprises an IGBT group, a first inversion filter capacitor, a second inversion filter capacitor and a direct-current voltage-stabilizing capacitor;
the capacitor in the inversion or rectification unit component is selected from Japanese Hitachi original large-capacity electrolytic capacitors, 2 strings and 4 parallel capacitors are adopted, and the types of the capacitors are as follows: HCGFA-4700MFD-450VDC, the power device adopts German Yingfei IGBT, IGBT + IGBT drive model respectively: FF450R12ME4+2SP0115T2A 0-12;
in the inversion or rectification unit component, an IGBT group is formed by connecting 6 IGBTs and 6 compensation capacitors in parallel, the IGBT group is connected with the first inversion or rectification filter capacitor, the first inversion or rectification filter capacitor is connected with the direct current voltage stabilizing capacitor, the direct current voltage stabilizing capacitor is connected with the second inversion or rectification filter capacitor, the second inversion or rectification filter capacitor is connected with the IGBT group, and the IGBT group is connected with a direct current output port;
by adopting the fully-controlled IGBT power module, the switching frequency is 10kHz, the size of the filter reactor can be reduced by 50%, the loss is reduced by 10%, the response speed is improved to within 1ms, the output precision reaches 0.5%, and the volt-ampere characteristic and the 24-hour operation curve of the load can be set at will.
The sensor unit component comprises a current sensor element, a voltage sensor element and an intelligent three-phase electric parameter meter;
the current sensor is connected with the inversion or rectification unit component and the digital display ammeter;
the voltage sensor is connected with the filter unit assembly and the digital display ammeter;
the sensor unit component is a Lyme sensor, and the model LT108-S of the current, direct voltage and current Lyme sensor is the same as that of the current and direct voltage;
the power unit component 2 is a DSP controller unit component, and 4 TI latest DSP chips with the model of TMS320F28335 are adopted;
the power unit element is connected with the control unit component and the inversion or rectification unit component;
the control unit assembly comprises a switch unit, an RLC load unit and a current transformer unit and is used for outputting and controlling signals of the circuit operation condition; the PLC load unit is Siemens 200 series PLC, model: 6ES 7214-2 AD23-0XB8,
the filter unit component comprises a filter capacitor and a reactor;
the filter capacitor consists of a first filter capacitor CA, a second filter capacitor CB and a third filter capacitor CC;
the reactor consists of a first reactor, a second reactor and a third reactor;
the filter unit component is connected with the inversion or rectification unit component and the transformer unit component;
wherein the model of the main loop direct current breaker is CM 1-160C/3300-160A;
the model of the main loop AC circuit breaker is CM 1-100C/3300-100A;
the AC contactor is _ LC1-D95M7C _95A-220V-50/60Hz _ Schneider;
the rated voltage of the alternating current side is 380V, the rated voltage of the direct current side is 500V, and the direct current voltage stabilizing capacitor is 900V; the meter on the panel displays the direct voltage, direct current, three-phase voltage, three-phase current, active power, reactive power and power factors of the device; the device is provided with a power supply, an operation and fault state display lamp; sudden stop and reset; the PLC is included, and remote control and system expansion can be carried out; the protection contactor comprises a pre-charging circuit, protects a contactor contact and prevents the tripping of the previous stage, comprises phase sequence protection and isolated island protection, and meets the safety requirement.
As shown in figure 2, the invention also designs a pre-charging function, the pre-charging module pre-charges the DC voltage-stabilizing capacitor C, the main contactor is in an off state, the main loop is closed and then the main contactor is closed to bypass the pre-charging resistor after delaying for 3 seconds, thus preventing the device from being damaged due to the large impact current generated at the moment of electrifying the power supply.
The above-described embodiments are merely illustrative of the preferred embodiments of the present invention, and do not limit the scope of the present invention, and various modifications and improvements of the technical solutions of the present invention can be made by those skilled in the art without departing from the spirit of the present invention, and the technical solutions of the present invention are within the scope of the present invention defined by the claims.
Claims (10)
1. An electronic load simulation system is characterized by comprising a three-phase pulse width modulation converter system, wherein the three-phase pulse width modulation converter system comprises a first three-phase pulse width modulation converter system and a second three-phase pulse width modulation converter system;
the three-phase pulse width modulation inverter system comprises: the device comprises an inversion or rectification unit component, a sensor unit component, a power unit component, a control unit component, a filter unit component, a transformer unit component, a direct current port component and an alternating current port component;
the inversion or rectification unit component is connected with the sensor unit component and the controller unit component;
the sensor unit component is connected with the inversion or rectification unit component, the filter unit component and the alternating current port component;
the power unit component is connected with the control unit component and the inversion or rectification unit component;
the control unit assembly is connected with the power unit assembly and the direct current port assembly;
the filter unit component is connected with the inversion or rectification unit component and the transformer unit component;
the transformer unit assembly is connected with the sensor assembly and the alternating current port assembly.
2. The electronic load simulation system of claim 1, wherein:
the inversion or rectification unit component comprises an IGBT group, a first inversion or rectification filter capacitor, a second inversion or rectification filter capacitor and a direct-current voltage-stabilizing capacitor;
the IGBT group is connected with the first inversion or rectification filter capacitor, the first inversion or rectification filter capacitor is connected with the direct current voltage stabilizing capacitor, the direct current voltage stabilizing capacitor is connected with the second inversion or rectification filter capacitor, the second inversion or rectification filter capacitor is connected with the IGBT group, and the IGBT group is connected with the direct current input port.
3. The electronic load simulation system of claim 1, wherein:
the sensor unit component comprises a current sensor element, a voltage sensor element and an intelligent three-phase electric parameter meter;
the current sensor unit element is connected with the inversion or rectification unit component and the digital display ammeter;
the voltage sensor is connected with the filter unit assembly and the digital display voltmeter;
the intelligent three-phase electric parameter meter is connected with the current sensor element and the alternating current port assembly.
4. The electronic load simulation system of claim 1, wherein:
the power unit element is a DSP controller, and the DPS controller comprises a first DSP chip, a second DSP chip, a third DSP chip and a fourth DSP chip.
5. The electronic load simulation system of claim 1, wherein:
the control unit assembly comprises a switch unit and a current transformer unit and is used for outputting and controlling signals of the circuit operation condition;
the current transformer unit is connected with the alternating current output port.
6. The electronic load simulation system of claim 5, wherein:
the control unit assembly further comprises an RLC load unit for performance detection of the electronic analog load system.
7. The electronic load simulation system of claim 1, wherein:
the filter unit component comprises a filter capacitor and a reactor;
the filter capacitor comprises: a first filter capacitor, a second filter capacitor, a third filter capacitor;
the reactor includes: the reactor comprises a first reactor, a second reactor and a third reactor.
8. The electronic load simulation system of claim 1, wherein:
the power supply also comprises a pre-charging module, the pre-charging module pre-charges the direct-current voltage-stabilizing capacitor C, the main contactor is in an off state, the main circuit is switched on and then the main contactor is closed for delaying 3 seconds and then the main contactor is closed to bypass the pre-charging resistor, and the pre-charging module is used for preventing the power supply from generating large impact current at the moment of electrifying and damaging the device.
9. The electronic load simulation system of claim 1, wherein:
the first three-phase pulse width modulation converter system and the second three-phase pulse width modulation converter system are connected through a direct current port.
10. The electronic load simulation system of claim 1, wherein:
the first three-phase pulse width modulation converter system is in a rectification working mode;
the second three-phase pulse width modulation converter system is in an inversion working mode.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010742172.1A CN111865102A (en) | 2020-07-29 | 2020-07-29 | Electronic type analog load system |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010742172.1A CN111865102A (en) | 2020-07-29 | 2020-07-29 | Electronic type analog load system |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112838774A (en) * | 2020-12-30 | 2021-05-25 | 合肥科威尔电源系统股份有限公司 | Control method of high-power RLC alternating current electronic load |
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| CN107064698A (en) * | 2017-06-09 | 2017-08-18 | 广州供电局有限公司 | Voltage dip simulation system and method |
| CN107769247A (en) * | 2017-10-19 | 2018-03-06 | 中国电力科学研究院有限公司 | A kind of RLC load simulation systems and its control method for the detection of anti-isolated island |
| CN111313676A (en) * | 2020-03-18 | 2020-06-19 | 许昌许继风电科技有限公司 | Servo driver soft start system and control method thereof |
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2020
- 2020-07-29 CN CN202010742172.1A patent/CN111865102A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107064698A (en) * | 2017-06-09 | 2017-08-18 | 广州供电局有限公司 | Voltage dip simulation system and method |
| CN107769247A (en) * | 2017-10-19 | 2018-03-06 | 中国电力科学研究院有限公司 | A kind of RLC load simulation systems and its control method for the detection of anti-isolated island |
| CN111313676A (en) * | 2020-03-18 | 2020-06-19 | 许昌许继风电科技有限公司 | Servo driver soft start system and control method thereof |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112838774A (en) * | 2020-12-30 | 2021-05-25 | 合肥科威尔电源系统股份有限公司 | Control method of high-power RLC alternating current electronic load |
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