CN103731017A - Short-circuit protection system of energy-storage bidirectional converter - Google Patents
Short-circuit protection system of energy-storage bidirectional converter Download PDFInfo
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- CN103731017A CN103731017A CN201310734002.9A CN201310734002A CN103731017A CN 103731017 A CN103731017 A CN 103731017A CN 201310734002 A CN201310734002 A CN 201310734002A CN 103731017 A CN103731017 A CN 103731017A
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Abstract
Provided is a short-circuit protection system of an energy-storage bidirectional converter. The short-circuit protection system comprises an AC side short-circuit protection module and a DC side short-circuit protection module, the two modules are designed independently and integrated inside a PCS, modular design is adopted by both protection, the AC side short-circuit protection module mainly comprises a diode three-phase full-bridge rectifier module, a high-power thyristor and resistors, and the DC side short-circuit protection module is formed by a high-power thyristor and resistors. The AC side short-circuit protection module is connected with a power conversion unit of the PCS in parallel, a three-phase supply firstly passes through the diode three-phase full-bridge rectifier module, then after the positive pole of a DC voltage output by a common cathode of the diode three-phase full-bridge rectifier module passes through the high-power thyristor, firstly the positive pole of the DC voltage passes through the resistors and finally flows back to a common anode of the diode three-phase full-bridge rectifier module, and a short-circuit protection loop is formed. The DC side short-circuit protection module is connected on a DC bus capacitor in parallel, the positive pole of a DC bus voltage firstly passes through the high-power thyristor, and then flows back to a DC bus negative pole through an absorption resistor, and the short-circuit protection loop is formed.
Description
Technical field
The invention belongs to energy-storage system field, be applicable to various energy accumulation current converters, in order to realize the short-circuit protection design to AC network side and load-side.
Background technology
At present; energy storage two way convertor is relatively many in the application of distribution network system; power distribution network is mainly comprised of overhead transmission line, cable, shaft tower, distribution transformer, isolating switch, reactive compensation capacitor and some affiliated facilities etc.; because the network of power distribution network forms feature and line connection; very easily there is single-phase shorted to earth; the faults such as phase fault are very necessary so energy storage two way convertor possesses the function of short-circuit protection.
The short-circuit protection of energy storage two way convertor routine all utilizes circuit breaker to realize; when the inside of electrical network or PCS is short-circuited fault; after the magnetic element short circuit current flow of circuit breaker inside, can trigger release action; realize short-circuit protection, also have careful current transformer producer to utilize circuit breaker to coordinate the short-circuit protection of realizing PCS together with fuse.But; these short-circuit protections are all mechanical protections; first; magnetic is threaded off and is had certain machine error, and has certain time of delay during mechanical action, and what have even can reach a few tens of milliseconds; before possible circuit breaker tripping; short trouble is eliminated, and PCS recovers normal condition, and this just cannot guarantee the safe and stable operation of PCS completely.
Summary of the invention
The application's goal of the invention: the method for designing of the energy storage two way convertor short circuit protection system that the application proposes; utilize short circuit protection module and circuit breaker to combine the short-circuit protection of realizing PCS; can guarantee the safety of PCS critical power ratio device completely; guarantee the stable operation of energy-storage system, can not cause burning of electrical network, energy-storage travelling wave tube and line load equipment.Short circuit protection module is protected fast as the Microsecond grade of PCS; circuit breaker is protected at a slow speed as the Millisecond of PCS; can solve the shortcoming of carrying out line short protection by circuit breaker merely completely; in the dropout ability while that guarantees circuit breaker; also further improved the response time of PCS cutting-off of short-circuit fault; fault coverage is dwindled, improved fail safe and the useful life of PCS.
Concrete scheme of the present invention is as follows:
A short circuit protection system for energy storage two way convertor, is characterized in that:
The short circuit protection system of described energy storage two way convertor PCS has AC short circuit protection module and DC side protection module, and two kinds of modules design separately, is all integrated in energy storage two way convertor PCS inside.
Wherein AC short circuit protection module is in parallel with the power conversion unit of PCS at AC; described AC short circuit protection module is comprised of diode three phase full bridge rectification module, AC short-circuit protection high-power thyristor and resistance; the ac input end of described three phase full bridge rectification module is connected on the three-phase circuit of power conversion unit AC of PCS, and the DC output end of described three phase full bridge rectification module and AC short-circuit protection high-power thyristor and resistance are connected in series.
Dc-side short-circuit protection module is connected between the DC bus positive pole and negative pole of PCS, and described dc-side short-circuit protection module is composed in series by dc-side short-circuit protection high-power thyristor and resistance.
Two kinds of protection module controls completely independent from one another, are furnished with gate trigger circuit separately.AC short circuit protection module is comprised of diode three phase full bridge rectification module, high-power thyristor and resistance, when there is short trouble in grid side or the situation such as is disturbed, AC short-circuit protection thyristor is with the speed fast conducting of Microsecond grade, PCS is protected fast, for short circuit energy provides bleed-off circuit, guarantee the safety of the inner critical power ratio device of PCS; AC circuit breaker belongs to protection at a slow speed, and after the action of AC short circuit protection module, circuit breaker is threaded off rapidly, thoroughly open failure system.
Dc-side short-circuit protection module is comprised of high-power thyristor and resistance; when there is energy-storage travelling wave tube short circuit or DC bus positive pole, negative pole short circuit; the first trigger action of dc-side short-circuit protection high-power thyristor; the portion of energy of releasing; restriction flows into the short circuit energy of power device or energy-storage travelling wave tube; then DC circuit breaker is threaded off rapidly, completely disengagement failure system.
AC short circuit protection module and dc-side short-circuit protection module also can cooperatively interact and carry out the short-circuit protection function of PCS inside, at PCS, detect after fault-signal, which kind of protection location positioning with fault point preferentially takes, if fault point is at AC, preferentially trigger harmonics module, DC side is protected in support; If, in DC side, can first trigger by DC side protection module fault point, AC is protected in support.So not only can realize main-apparatus protection, but also be equivalent to when short-circuit protection, there be " dual fail-safe ".
The present invention has following technique effect:
Energy storage two way convertor PCS is mainly comprised of power electronic power device, filter reactor, DC support electric capacity etc.; in pcs system; the ability that power electronic device is born short circuit current is the most weak; and operate time of protection is all Microsecond grade; and the short circuit drop-away time representative value of circuit breaker is Millisecond; utilize circuit breaker to realize the short-circuit protection of PCS; cannot really play the effect of protection power device; can only protection reactor, the device such as capacitor, switch, cannot meet the requirement of PCS to protection reliability, accuracy, quick-action at all.
The impact that the short circuit protection system of described energy storage two way convertor PCS can cause short trouble drops to minimum; when PCS power conversion unit seals pulse because of short trouble; the speed of Microsecond grade triggers power electronics earial drainage loop; can solve that circuit breaker short circuit guard time is long, main contacts adhesion cannot rapid-releasing etc. situation; can improve antijamming capability and the protection class of energy storage two way convertor PCS; reduce failure rate and the maintenance times of PCS, guarantee the working life of PCS.
Accompanying drawing explanation
The energy storage two way convertor topological structure schematic diagram of accompanying drawing 1 for comprising short circuit protection module;
Accompanying drawing 2 is AC short circuit protection module topological structure and wiring schematic diagram;
Accompanying drawing 3 is dc-side short-circuit protection module topological structure and wiring schematic diagram.
Embodiment
Below according to Figure of description and in conjunction with specific embodiments to further statement in detail of technical scheme of the present invention.
1) energy storage two way convertor pcs system forms
Contain the energy storage two way convertor PCS topological structure of short circuit protection system as shown in Figure 1, system is mainly comprised of AC circuit breaker Q F1, LCL filter, ac short circuit protection module (shown in accompanying drawing 2), power conversion unit, high-frequency absorption capacitor C 1/C2/C3, DC bus Support Capacitor C_Bus, direct-current short circuit protection module (shown in accompanying drawing 3), DC circuit breaker QF2 and energy-storage travelling wave tube etc.
Three-phase alternating current electrical network first accesses the end of incoming cables of energy storage two way convertor PCS AC QF1 circuit breaker, and the leading-out terminal of QF1 circuit breaker is connected with the carrying out end of L1 reactor, belongs to series relationship; The leading-out terminal of L1 reactor is connected with the end of incoming cables of 3 RC resistance-capacitance circuits and the end of incoming cables of L2 reactor respectively, and 3 RC resistance-capacitance circuits belong to relation in parallel with L2 reactor; The leading-out terminal of 3 RC resistance-capacitance circuits carries out short circuit; The leading-out terminal of L2 reactor is connected with the end of incoming cables of ac short circuit protection module and the end of incoming cables of power conversion unit respectively, and ac short circuit protection module belongs to relation in parallel with power conversion unit; The full-control type device that power conversion unit adopts is that IGBT(contains anti-paralleled diode), power conversion unit is three phase full bridge structure, high-frequency absorption capacitor C 1 in parallel between the direct-flow positive pole of A phase half-bridge, negative pole, high-frequency absorption capacitor C 2 in parallel between the direct-flow positive pole of B phase half-bridge, negative pole, high-frequency absorption capacitor C 3 in parallel between the direct-flow positive pole of C phase half-bridge, negative pole, the direct-flow positive pole parallel connection of three-phase, the parallel connection of direct current negative pole, respectively as the leading-out terminal of power conversion unit direct-flow positive pole bus and direct current negative pole bus; Power conversion unit leading-out terminal is relation in parallel with DC bus Support Capacitor C_Bus, and the positive terminal of C_Bus is connected with the positive electrode bus of power conversion unit, and the negative terminal of C_Bus is connected with the negative pole bus of power conversion unit; Direct-current short circuit protection module is relation in parallel with power conversion unit, and the end of incoming cables of direct-current short circuit protection module is connected with the positive electrode bus of power conversion unit, and the leading-out terminal of direct-current short circuit protection module is connected with the negative pole bus of power conversion unit; Inlet wire positive terminal, the negative terminal of DC circuit breaker QF2 are connected with direct-flow positive pole bus and the direct current negative pole bus of power conversion unit respectively, belong to series relationship, QF2 leading-out terminal and energy-storage travelling wave tube are connected in series, and finally realize the electrical connection of whole energy-storage system.
2) ac short circuit protection module forms and parts selection explanation
As shown in Figure 2, this module is mainly comprised of diode three phase full bridge rectification module, high-power thyristor and resistance the topology of ac short circuit protection module.The end of incoming cables of protection module is exactly the three-phase input terminal of diode rectification module; the common cathode of diode rectification module and the anodic bonding of thyristor; the negative electrode of thyristor is connected with one end of resistance; the common anodic bonding of the other end of resistance and diode; ac short circuit protection module only has end of incoming cables, and the end of incoming cables of end of incoming cables and power conversion unit is connected in parallel.
During PCS normal operation, this module is not worked; When there is short-circuit conditions in external electrical network or PCS inside, the action that is triggered of this module, again because the maximum current that IGBT device can bear is about 4 times of rated value, so when carrying out the parts selection of ac short circuit protection module, the rated operational current of diode and thyristor is at least 4 times of IGBT rated current of devices; Resistance, as the main consumable part of electric energy, should select absorbability strong, the resistor that heat-resistant quality is good.
3) direct-current short circuit protection module forms and parts selection explanation
As shown in Figure 3, this module is mainly comprised of high-power thyristor and resistance the topology of direct-current short circuit protection module.The end of incoming cables of protection module is exactly the anode of thyristor, and the negative electrode of thyristor is connected with one end of resistance, and the other end of resistance is the leading-out terminal of protection module, and this module is connected in parallel between the direct-flow positive pole bus and direct current negative pole bus of power conversion unit.
During PCS normal operation, this module is not worked; When there is short trouble in external electrical network short circuit, energy-storage travelling wave tube short circuit or PCS inside, the action that is triggered of this module, again because after dc-side short-circuit generation, conventionally the rated operational voltage of this thyristor is accompanied by the situation that dc-link capacitance C_Bus voltage occurs that pump rises, so at least should be 2 times of IGBT device rated voltage; Rated working current value should be at least 4 times of IGBT rated current of devices.Resistance, as the main consumable part of electric energy, should select absorbability strong, the resistor that heat-resistant quality is good.
4) course of work of short circuit protection system
The situation that occurs short trouble take grid side or pcs system below, as example, is simply introduced the course of work of short circuit system:
When being short-circuited fault, PCS controller collects after fault-signal, enter into short-circuit protection mode of operation, first stop the triggering signal of power conversion unit, then trigger respectively successively thyristor SCR1, the gate pulse signal of SCR2, part fault current is absorbed by harmonics module resistance R 1, and another part fault current that flows through power model is absorbed by direct current protecting module resistance R 2 simultaneously, guaranteed like this safety of power conversion unit, avoided again dc-link capacitance that overcurrent and superpotential situation can not occur, so far, the short circuit current of grid side is absorbed fast, then AC circuit breaker Q F1 and DC side circuit breaker Q F2 are transmitted tripping, after both sides circuit breaker disconnects completely, the protection module of AC and DC side is owing to not having forward voltage to automatically shut down, PCS normal shutdown.
Short trouble eliminate after, PCS detect external electrical network normal, unfaulty conditions open into, autoboot, enters the running status before fault.
Claims (7)
1. a short circuit protection system for energy storage two way convertor, is characterized in that:
The short circuit protection system of described energy storage two way convertor PCS has AC short circuit protection module and DC side protection module, and two kinds of modules design separately, is all integrated in energy storage two way convertor PCS inside.
2. the short circuit protection system of energy storage two way convertor according to claim 1, is characterized in that:
AC short circuit protection module is in parallel with the power conversion unit of PCS at AC; described AC short circuit protection module is comprised of diode three phase full bridge rectification module, AC short-circuit protection high-power thyristor and resistance; the ac input end of described three phase full bridge rectification module is connected on the three-phase circuit of power conversion unit AC of PCS, and the DC output end of described three phase full bridge rectification module and AC short-circuit protection high-power thyristor and resistance are connected in series.
3. the short circuit protection system of energy storage two way convertor according to claim 1, is characterized in that:
Dc-side short-circuit protection module is connected between the DC bus positive pole and negative pole of PCS, and described dc-side short-circuit protection module is composed in series by dc-side short-circuit protection high-power thyristor and resistance.
4. according to the short circuit protection system of the energy storage two way convertor described in claim 1-3 any one claim, it is characterized in that:
Two kinds of protection module controls completely independent from one another, are furnished with gate trigger circuit separately.
5. according to the short circuit protection system of the energy storage two way convertor described in claim 1-3 any one claim, it is characterized in that:
For AC short circuit protection module, when grid side occurs short trouble or is disturbed, AC short-circuit protection thyristor, with the speed fast conducting of Microsecond grade, is protected fast to PCS, for short circuit energy provides bleed-off circuit, guarantee the safety of the inner critical power ratio device of PCS; AC circuit breaker in PCS belongs to protection at a slow speed, and after the action of AC short circuit protection module, circuit breaker is threaded off rapidly, thoroughly open failure system.
6. according to the short circuit protection system of the energy storage two way convertor described in claim 1-3 any one claim, it is characterized in that:
For dc-side short-circuit protection module; when there is energy-storage travelling wave tube short circuit or DC bus positive pole, negative pole short circuit; the first trigger action of dc-side short-circuit protection high-power thyristor; the portion of energy of releasing; restriction flows into the short circuit energy of power device or energy-storage travelling wave tube; then the DC circuit breaker in PCS is threaded off rapidly, completely disengagement failure system.
7. according to the short circuit protection system of the energy storage two way convertor described in claim 1-6 any one claim, it is characterized in that:
AC short circuit protection module and dc-side short-circuit protection module can cooperatively interact and carry out the short-circuit protection function of PCS inside, at PCS, detect after fault-signal, if harmonics module, at AC, is preferentially triggered in fault point, DC side is protected in support; If, in DC side, can first trigger by DC side protection module fault point, AC is protected in support.
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| CN201310734002.9A CN103731017A (en) | 2013-12-26 | 2013-12-26 | Short-circuit protection system of energy-storage bidirectional converter |
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| CN104767185A (en) * | 2015-03-20 | 2015-07-08 | 浙江大学 | Convertor station having direct current fault clearance capacity and control method of convertor station |
| CN107123993A (en) * | 2017-07-13 | 2017-09-01 | 东莞市阿特为电气有限公司 | Switching circuit |
| CN109193573A (en) * | 2018-10-24 | 2019-01-11 | 西安特锐德智能充电科技有限公司 | Storage medium, the short-circuit protection control method of bidirectional power converter, apparatus and system |
| CN109698496A (en) * | 2017-10-20 | 2019-04-30 | 株洲中车时代电气股份有限公司 | A kind of rail traffic tractive power supply system and control method |
| CN110277764A (en) * | 2019-07-24 | 2019-09-24 | 阳光电源股份有限公司 | A kind of power grid overvoltage crowbar and method |
| CN112952745A (en) * | 2021-04-16 | 2021-06-11 | 阳光电源股份有限公司 | Photovoltaic system, short-circuit protection method and device thereof, and inverter |
| CN112994150A (en) * | 2021-02-05 | 2021-06-18 | 北京四方继保自动化股份有限公司 | Overcurrent and overvoltage fault protection system and method for V2G charging pile |
| CN113644630A (en) * | 2021-09-17 | 2021-11-12 | 锦浪科技股份有限公司 | Method for coping with half-bus short-circuit fault of three-level inverter circuit |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN112994150A (en) * | 2021-02-05 | 2021-06-18 | 北京四方继保自动化股份有限公司 | Overcurrent and overvoltage fault protection system and method for V2G charging pile |
| CN112952745A (en) * | 2021-04-16 | 2021-06-11 | 阳光电源股份有限公司 | Photovoltaic system, short-circuit protection method and device thereof, and inverter |
| CN113644630A (en) * | 2021-09-17 | 2021-11-12 | 锦浪科技股份有限公司 | Method for coping with half-bus short-circuit fault of three-level inverter circuit |
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Application publication date: 20140416 |