CN102299523A - Dynamic voltage restorer for three-phase four-line system power distribution network - Google Patents
Dynamic voltage restorer for three-phase four-line system power distribution network Download PDFInfo
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- CN102299523A CN102299523A CN2011102420827A CN201110242082A CN102299523A CN 102299523 A CN102299523 A CN 102299523A CN 2011102420827 A CN2011102420827 A CN 2011102420827A CN 201110242082 A CN201110242082 A CN 201110242082A CN 102299523 A CN102299523 A CN 102299523A
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Abstract
The invention relates to a dynamic voltage restorer for a three-phase four-line system power distribution network, which comprises a coupling unit, bridge type inverters, a filtering unit, a direct current energy storage unit and a charging unit, wherein the coupling unit is connected in series between an access electric network and the output end of the restorer, the bridge type inverters are connected with the coupling unit, the charging unit is used for charging the direct current energy storage unit, the secondary sides of three single-phase transformers (TA, TB and TC) isolated by the coupling unit are respectively connected in series into a three-phase power supply electric network, and the primary sides of the three single-phase transformers (TA, TB and TC) are respectively connected with the filtering unit at the inverter side, three bidirectional thyristors are respectively connected in parallel with the secondary sides of the three single-phase transformers (TA, TB and TC) to be used as electronic switches. Three contactors are used for respectively carrying out switching control on the three bidirectional thyristors. The input ends of the three single-phase bridge type inverters are connected in parallel and are then connected in parallel with a super energy storage capacitor C1, the super energy storage capacitor C1 is connected with the output end of a three-phase full-bridge rectifying circuit through a charging resistor R, and the input end of the three-phase full-bridge rectifying circuit is connected to the access electric network end Us through the three-phase transformer T.
Description
Technical field
The present invention relates to a kind of dynamic electric voltage recovery device that is used for the three-phase four-wire system power distribution network, belong to electric and electronic technical field.Be that research power application semiconductor switch device is realized the conversion of electric energy and a special kind of skill of control, be called power electronic technology again.
Background technology
Use modern power electronics technology can realize the control of the quality of power supply, for the user provides specific supply of electrical energy, the main at present device that uses has distribution system static compensator, active power filtering, dynamic electric voltage recovery device (DVR) etc.Dynamic electric voltage recovery device (DVR) is the series compensation device that has energy storage device, except that reactive power, the ability of compensation active power is arranged.
When system voltage is interfered, usually cause the load side short time voltage to fall or jump (duration is generally several cycles to tens cycle).This is to cause the sensitive kinds load to have a power failure the main cause of computer equipment, precision equipment and instrument failure.Dynamic electric voltage recovery device (DVR) produces bucking voltage within 1～2 millisecond, the interference that bucking-out system voltage is suffered makes the impression of load side voltage less than disturbance, has guaranteed the safe and reliable operation of sensitive kinds load, computer equipment, precision equipment and instrument.
Dynamic electric voltage recovery device (DVR) governing response speed is fast, can guarantee that the load side voltage waveform is a standard sine, eliminates voltage harmonic, voltage fluctuation and the flickering influence to load.
The voltage unbalanced fault when taking place in three characteristics of the middle term four-wire system power distribution network, unaffected for guaranteeing the load side voltage waveform, zero-sequence component needs compensation, adopted in the past three independently dynamic electric voltage recovery device (DVR) compensate, have investment and the bigger problem of running wastage.
Summary of the invention
The objective of the invention is to propose a kind of dynamic electric voltage recovery device that is used for the three-phase four-wire system power distribution network, with three independently the dc energy storage unit of dynamic electric voltage recovery device (DVR) be merged into a dc energy storage unit, reduced the quantity of energy-storage units, and reduced the charging device that charges to dc energy storage unit, thereby reduced investment; The present invention simultaneously adopts thyristor to make dynamic electric voltage recovery device (DVR) just often be in bypass condition at line voltage, make electrical network pass through the thyristor powering load, substitute the higher switching loss of inverter with lower thyristor on-state loss, reduced operating cost.
Technical scheme of the present invention: the dynamic electric voltage recovery device that is used for the three-phase four-wire system power distribution network of the present invention comprises access electrical network end Us and restorer output Uc, be connected on the coupling unit that inserts between electrical network end Us and the restorer output Uc, the bridge-type inverter that is connected with coupling unit, filter unit, dc energy storage unit and the charhing unit that dc energy storage unit is charged, its coupling unit comprises three single-phase transformer TA that are used to isolate, TB, the secondary of TC seals in the A phase of three phase supply electrical network respectively, the B phase, the C phase, three single-phase transformer TA, TB, the former limit of TC and inverter side filter unit link to each other three bidirectional thyristor SCR_A, SCR_B and SCR_C are connected in parallel on three single-phase transformer TA respectively, TB, the secondary of TC is as electronic switch.
In the contact of inserting the first A.C. contactor KM1 that connects between electrical network end Us and the coupling unit, the 3rd contactor KM3 contact in parallel between electrical network end Us and the restorer output Uc inserted in connect between the secondary of three single-phase transformer TA, TB, TC and the restorer output Uc contact of the second A.C. contactor KM2.
The former limit of described three single-phase transformer TA, TB, TC is connected to the output of three single-phase bridge type inverters respectively by filter unit separately, after the input parallel connection of three single-phase bridge type inverters with super energy storage capacitor C1 and connect, super energy storage capacitor C1 is connected with the output of three-phase bridge rectification circuit by charging resistor R, and the input of three-phase bridge rectification circuit is connected to by three-phase transformer T and inserts electrical network end Us.
Described super energy storage capacitor C1 is in parallel with high-frequency filter capacitor C2, and the capacity of super energy storage capacitor C1 is 7～9 farads.
Beneficial effect of the present invention:
1, when mains supply voltage generation transient state fault, the present invention can inject bucking voltage to electrical network rapidly, and no matter is single-phase voltage fault, three-phase symmetric voltage fault or three-phase asymmetrical voltage fault, all can play compensating action;
2, only adopt a super energy storage capacitor group to carry out energy storage, volume is little, energy storage density is high, and device integral body expends low;
3, just often, the present invention is operated in the thyristor conducting state, and the on-state loss of thyristor is lower than the switching loss of inverter, thereby has reduced the running wastage of device at mains supply voltage;
4, the series coupled unit has adopted isolating transformer, can be applied to the mesohigh system;
Description of drawings
Fig. 1 is an overall circuit logic diagram of the present invention;
Fig. 2 is the circuit theory diagrams that are used for the dynamic electric voltage recovery device of three-phase four-wire system power distribution network of the present invention.
Embodiment
Fig. 1 is an overall circuit logic diagram of the present invention, and Fig. 2 is the circuit theory diagrams that the present invention is used for the dynamic electric voltage recovery device of three-phase four-wire system power distribution network:
The present invention includes and insert electrical network end Us and restorer output Uc, be connected on the coupling unit that inserts between electrical network end Us and the restorer output Uc, the bridge-type inverter that is connected with coupling unit, filter unit, dc energy storage unit and the charhing unit that dc energy storage unit is charged, its coupling unit comprises three single-phase transformer TA that are used to isolate, TB, the secondary of TC seals in the A phase of three phase supply electrical network respectively, the B phase, the C phase, three single-phase transformer TA, TB, the former limit of TC and inverter side filter unit link to each other three bidirectional thyristor SCR_A, SCR_B and SCR_C are connected in parallel on three single-phase transformer TA respectively, TB, the secondary of TC is as electronic switch.
In the contact of inserting the first A.C. contactor KM1 that connects between electrical network end Us and the coupling unit, the 3rd contactor KM3 contact in parallel between electrical network end Us and the restorer output Uc inserted in connect between the secondary of three single-phase transformer TA, TB, TC and the restorer output Uc contact of the second A.C. contactor KM2.
The former limit of described three single-phase transformer TA, TB, TC is connected to the output of three single-phase bridge type inverters respectively by filter unit separately, after the input parallel connection of three single-phase bridge type inverters with super energy storage capacitor C1 and connect, super energy storage capacitor C1 is connected with the output of three-phase bridge rectification circuit by charging resistor R, and the input of three-phase bridge rectification circuit is connected to by three-phase transformer T and inserts electrical network end Us.Described super energy storage capacitor C1 is in parallel with high-frequency filter capacitor C2, and the capacity of super energy storage capacitor C1 is 7～9 farads.
Contactor KM1, KM2 and KM3 are used for carrying out the control of switching, and the mechanical by-pass switch when KM3 is used for the load overcurrent, bidirectional thyristor SCR_A, SCR_B and SCR_C just often are in conducting state as electronic switch at power supply grid voltage, be electric, reduce the loss of DVR device; Isolating transformer TA, TB and TC are used for the injection of bucking voltage when line voltage breaks down.
The element that described filter unit comprises has: three inductance L 1, L2 and L3 and three capacitor C 1, C2 and C3 connect into three single-phase LC filters, the output of three LC filters links to each other with the primary side end mouth of isolating transformer TA, TB and TC respectively, is used for the ripple that the filtering bridge-type inverter is exported the switching frequency that produces on the bucking voltage.
Described bridge-type inverter comprises: the A phase inverter of being made up of GA1～GA4; The B phase inverter of forming by GB1～GB4; The C phase inverter of forming by GC1～GC4.The direct-flow input end of three single-phase full-bridge inverters is parallel to the two ends of super energy storage capacitor C1; Bucking voltage when bridge-type inverter is used to export the line voltage fault.
Described dc energy storage unit comprises super energy storage capacitor C1 and high-frequency filter capacitor C2.The two ends of super energy storage capacitor C1 and the direct-flow input end that is connected to described bridge-type inverter after the two ends of high-frequency filter capacitor C2 are in parallel; Dc energy storage unit be used to the to afford redress energy of line voltage.
Described charhing unit comprises 1 three-phase isolation boosting transformer T, 6 three-phase bridge rectification circuit and charging resistor R that Power Diode Pumped D1～D6 forms.The input of three-phase isolation boosting transformer T gets access to grid, the output of the input termination three-phase isolation boosting transformer T of three-phase bridge rectification circuit, link to each other with the positive port of described super energy storage capacitor C1 behind the cathode series resistance R of the output of three-phase bridge rectification circuit, its negative pole directly links to each other with the negative terminal mouth of super energy storage capacitor C1; Charhing unit is used for charging to dc energy storage unit.
Below introduce operation principle of the present invention in detail:
As Fig. 2: during system initialization, all switching devices of series coupled unit all are in off-state, and at first only closed KM3 makes the present invention be operated in the contactor bypass condition, closed then KM1, KM2 and conducting thyristor SCR_A, SCR_B and SCR_C; Disconnect KM3 afterwards, make the present invention be operated in thyristor conducting power supply state.
When detecting power supply grid voltage and the transient state fault occurs, take the measure cutoff thyristor of quick cutoff thyristor.Then, the bridge-type inverter of three-phase begins super energy storage capacitor C1 energy stored inversion output bucking voltage is injected into electrical network by isolating transformer TA, TB and TC, and the voltage of load-side is remained unchanged.
The present invention has adopted ultracapacitor to carry out energy storage, compares traditional batteries to store energy, and volume is little, the energy storage density height, and can carry out the big electric current charge and discharge of long period, but make both falling of compensation network voltage of the present invention, but also jumping of compensation network voltage.To the charging device that ultracapacitor charges, only adopt three-phase not control rectification serial connection current-limiting resistance and get final product, simple in structure.
The present invention just often adopts thyristor to electric at line voltage, with traditional employing inverter offset zero voltage or directly on all of conducting full-bridge inverter (descending) pipe compare, on-state loss is little.When detecting power supply grid voltage and the transient state fault occurs, by the suitable voltage of bridge-type inverter output the electric current that flows through thyristor is reduced in the time of the 1ms left and right sides and keep below the electric current, make thyristor at utmost point reliable turn-off in the short time.
The series coupled unit adopts three single-phase isolating transformers among the present invention, require its leakage impedance less, on the one hand being less with the voltage-phase deviation of injecting electrical network for the output voltage that guarantees full-bridge inverter, is to keep below the electric current in order can within a short period of time when forcing cutoff thyristor the electric current of thyristor to be dropped on the other hand.
Inverter unit adopts the single-phase full bridge topology of three independent controls among the present invention, and the series coupled unit has adopted isolating transformer, makes the present invention both can be applicable to the compensation of three-phase four-wire system power distribution network, also can promote the use in middle and high voltage transmission system.
The present invention has reduced the quantity of dc energy storage unit and to the charging device that dc energy storage unit charges, has reduced cost consumption; At power supply grid voltage just often, the present invention is operated in the thyristor power supply state, and loss ratio working method in the past is low, and when power supply grid voltage generation transient state fault, cutoff thyristor and inject bucking voltage fast, and proof load voltage remains unchanged.
Claims (4)
1. dynamic electric voltage recovery device that is used for the three-phase four-wire system power distribution network, comprise and insert electrical network end Us and restorer output Uc, be connected on the coupling unit that inserts between electrical network end Us and the restorer output Uc, the bridge-type inverter that is connected with coupling unit, filter unit, dc energy storage unit and the charhing unit that dc energy storage unit is charged, it is characterized in that: coupling unit comprises three single-phase transformer TA that are used to isolate, TB, the secondary of TC seals in the A phase of three phase supply electrical network respectively, the B phase, the C phase, three single-phase transformer TA, TB, the former limit of TC and inverter side filter unit link to each other three bidirectional thyristor SCR_A, SCR_B and SCR_C are connected in parallel on three single-phase transformer TA respectively, TB, the secondary of TC is as electronic switch.
2. the dynamic electric voltage recovery device that is used for the three-phase four-wire system power distribution network according to claim 1, it is characterized in that: in the contact of inserting the first A.C. contactor KM1 that connects between electrical network end Us and the coupling unit, the 3rd contactor KM3 contact in parallel between electrical network end Us and the restorer output Uc inserted in connect between the secondary of three single-phase transformer TA, TB, TC and the restorer output Uc contact of the second A.C. contactor KM2.
3. the dynamic electric voltage recovery device that is used for the three-phase four-wire system power distribution network according to claim 1 and 2, it is characterized in that: the former limit of three single-phase transformer TA, TB, TC is connected to the output of three single-phase bridge type inverters respectively by filter unit separately, after the input parallel connection of three single-phase bridge type inverters with super energy storage capacitor C1 and connect, super energy storage capacitor C1 is connected with the output of three-phase bridge rectification circuit by charging resistor R, and the input of three-phase bridge rectification circuit is connected to by three-phase transformer T and inserts electrical network end Us.
4. the dynamic electric voltage recovery device that is used for the three-phase four-wire system power distribution network according to claim 3 is characterized in that: described super energy storage capacitor C1 is in parallel with high-frequency filter capacitor C2, and the capacity of super energy storage capacitor C1 is 7～9 farads.
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| CN2011102420827A CN102299523A (en) | 2011-08-23 | 2011-08-23 | Dynamic voltage restorer for three-phase four-line system power distribution network |
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| CN2011102420827A CN102299523A (en) | 2011-08-23 | 2011-08-23 | Dynamic voltage restorer for three-phase four-line system power distribution network |
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Cited By (12)
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| CN103457283A (en) * | 2013-09-17 | 2013-12-18 | 无锡力豪科技有限公司 | Super capacitor dynamic voltage recovery system and power supply system |
| CN104201685A (en) * | 2014-09-25 | 2014-12-10 | 武汉大学 | Quick turn-off method and system for by-pass thyristor of medium-voltage dynamic voltage restorer |
| CN104538974A (en) * | 2014-12-17 | 2015-04-22 | 刘文华 | Three-phase three-wire series connection type dynamic voltage compensator |
| CN106972506A (en) * | 2017-05-11 | 2017-07-21 | 成都瑞尔维轨道交通技术有限公司 | Distribution system and power system |
| CN107181262A (en) * | 2017-06-23 | 2017-09-19 | 上海能传电气有限公司 | A kind of dynamic electric voltage recovery device and its method of work for intersecting power taking |
| CN107317339A (en) * | 2017-06-13 | 2017-11-03 | 南京南瑞继保电气有限公司 | A kind of the voltage-source type adjusting means and its control method of multiple redundancy configuration |
| CN107359644A (en) * | 2017-08-17 | 2017-11-17 | 华中科技大学 | A kind of microgrid interface topology apparatus |
| CN107769217A (en) * | 2016-08-23 | 2018-03-06 | 江苏华峰电器控制设备有限公司 | A kind of dynamic electric voltage recovery device |
| CN110011317A (en) * | 2019-03-20 | 2019-07-12 | 浙江大学 | A kind of dynamic electric voltage recovery device based on soft switch circuit |
| CN110729736A (en) * | 2019-10-17 | 2020-01-24 | 深圳市盛弘电气股份有限公司 | Inverter module with bypass fast switching function, dynamic voltage compensation device and method |
| CN112531711A (en) * | 2020-12-03 | 2021-03-19 | 华中科技大学 | Medium-voltage power supply quality comprehensive adjusting system |
| CN113507219A (en) * | 2021-09-03 | 2021-10-15 | 江苏东方四通科技股份有限公司 | Water-cooling high-power medium-high frequency power supply device |
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Cited By (19)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103457283B (en) * | 2013-09-17 | 2016-01-20 | 无锡力豪科技有限公司 | A kind of super capacitor dynamic voltage recovery system and power-supply system |
| CN103457283A (en) * | 2013-09-17 | 2013-12-18 | 无锡力豪科技有限公司 | Super capacitor dynamic voltage recovery system and power supply system |
| CN104201685A (en) * | 2014-09-25 | 2014-12-10 | 武汉大学 | Quick turn-off method and system for by-pass thyristor of medium-voltage dynamic voltage restorer |
| CN104538974A (en) * | 2014-12-17 | 2015-04-22 | 刘文华 | Three-phase three-wire series connection type dynamic voltage compensator |
| CN104538974B (en) * | 2014-12-17 | 2016-09-14 | 刘文华 | A kind of phase three-wire three dynamic voltage compensator in series type |
| CN107769217A (en) * | 2016-08-23 | 2018-03-06 | 江苏华峰电器控制设备有限公司 | A kind of dynamic electric voltage recovery device |
| CN106972506A (en) * | 2017-05-11 | 2017-07-21 | 成都瑞尔维轨道交通技术有限公司 | Distribution system and power system |
| CN106972506B (en) * | 2017-05-11 | 2023-10-13 | 成都交达电气有限公司 | Power distribution system and power system |
| CN107317339A (en) * | 2017-06-13 | 2017-11-03 | 南京南瑞继保电气有限公司 | A kind of the voltage-source type adjusting means and its control method of multiple redundancy configuration |
| CN107181262B (en) * | 2017-06-23 | 2023-06-09 | 上海能传电气有限公司 | Dynamic voltage recovery device for cross power taking and working method thereof |
| CN107181262A (en) * | 2017-06-23 | 2017-09-19 | 上海能传电气有限公司 | A kind of dynamic electric voltage recovery device and its method of work for intersecting power taking |
| CN107359644A (en) * | 2017-08-17 | 2017-11-17 | 华中科技大学 | A kind of microgrid interface topology apparatus |
| CN110011317A (en) * | 2019-03-20 | 2019-07-12 | 浙江大学 | A kind of dynamic electric voltage recovery device based on soft switch circuit |
| CN110729736A (en) * | 2019-10-17 | 2020-01-24 | 深圳市盛弘电气股份有限公司 | Inverter module with bypass fast switching function, dynamic voltage compensation device and method |
| CN110729736B (en) * | 2019-10-17 | 2023-09-08 | 深圳市盛弘电气股份有限公司 | Inverter module with bypass fast-switching function, dynamic voltage compensation device and method |
| CN112531711A (en) * | 2020-12-03 | 2021-03-19 | 华中科技大学 | Medium-voltage power supply quality comprehensive adjusting system |
| CN112531711B (en) * | 2020-12-03 | 2022-09-20 | 华中科技大学 | Medium-voltage power supply quality comprehensive adjusting system |
| CN113507219A (en) * | 2021-09-03 | 2021-10-15 | 江苏东方四通科技股份有限公司 | Water-cooling high-power medium-high frequency power supply device |
| CN113507219B (en) * | 2021-09-03 | 2021-12-03 | 江苏东方四通科技股份有限公司 | Water-cooling high-power medium-high frequency power supply device |
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Application publication date: 20111228 |