CN202749820U - H-bridge cascaded SVG power unit circuit - Google Patents
H-bridge cascaded SVG power unit circuit Download PDFInfo
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- CN202749820U CN202749820U CN2012202576892U CN201220257689U CN202749820U CN 202749820 U CN202749820 U CN 202749820U CN 2012202576892 U CN2012202576892 U CN 2012202576892U CN 201220257689 U CN201220257689 U CN 201220257689U CN 202749820 U CN202749820 U CN 202749820U
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
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- Y02E40/10—Flexible AC transmission systems [FACTS]
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Abstract
The utility model discloses an H-bridge cascaded SVG power unit circuit, particularly, the utility model provides an H-bridge cascaded SVG power unit circuit applied to middle-high voltage. The H-bridge cascaded SVG power unit circuit of the utility model includes an H-bridge inverter circuit, a power supplying circuit, a discharge circuit, a bypass circuit and a controller which are electrically connected with each other, wherein the H-bridge inverter circuit is used for generating wattless power, the power supplying circuit is used for obtaining electric energy from a bus and providing the electric energy required by the driving of a power tube of the H-bridge inverter circuit and required by the operation of the controller, the discharge circuit is used for adjusting the capacitor voltage of the power unit circuit, the bypass circuit which is electrically connected with an alternating current port of the H-bridge inverter circuit is used for realizing redundancy control of an SVG, and the controller is used for sampling direct current voltage of the power supplying circuit and controlling the H-bridge inverter circuit, the discharge circuit and the bypass circuit.
Description
Technical field
The utility model relates to a kind of based on H bridge cascade connection type SVG power cell circuit.
Background technology
Development along with power electronic technology, traditional dynamic passive compensation (SVC) device is substituted by static reacance generator (SVG) device gradually, because be subjected to the restriction of present electronic power switch device, parallel connection type SVG is usually used in low-voltage power supply system reactive power compensation occasion.For the large capacity reactive compensation occasion of middle high-pressure, parallel connection type SVG main circuit generally needs the series and parallel of switching device, and multiplex and multilevel converter adopt the series and parallel of switching device need to solve the dynamic voltage balancing of device, equal flow problem; The transformer that adopts in the multiple technology has saturability and non-linear, brings the problems such as control is complicated, protection difficulty.Adopting multilevel converter is an important research direction that improves the SVG capacity, and multi-electrical level inverter mainly contains diode-clamped multi-electrical level inverter, striding capacitance type multi-electrical level inverter and H bridge cascade multilevel inverter.H bridge cascade multilevel inverter is compared with striding capacitance type multi-electrical level inverter with the diode-clamped multi-electrical level inverter, and its main circuit is simple, and the restriction owing to without clamping device is easy to realize larger number of levels.The topological structure of H bridge cascade multilevel inverter is applied among the SVG, can significantly improves voltage and the reactive compensation capacity of SVG, have broad application prospects.
Particularly in the high-voltage power electronic device, cascade of power units is the effective ways of raising capacity and electric pressure at power electronic equipment, and SVG adopts cascade of power units to realize high pressure and large capacity.Several problems below mesohigh H bridge cascade connection type SVG exists:
1, the voltage of SVG and capacity increase, and the power cell of cascade also increases, and makes the reliability decrease of SVG device;
2, the dc capacitor of each H bridge unit is separate among the H bridge cascade connection type SVG, and the equilibrium control of each H bridge capacitance voltage becomes a difficult point;
3, in power cell, it is a difficult point that the power supply of the driving power of power tube and power cell controller obtains;
4, the power cell current potential of H bridge cascaded high-voltage SVG is very high, needs the high pressure isolating problem between consideration H bridge power unit and the ground.
The utility model content
For the problems referred to above, the utility model provide a kind of can realize high-order electric capacity get can, the balanced control of Bypass Control and capacitance voltage based on H bridge cascade connection type SVG power cell circuit.
For achieving the above object, the utility model comprises H bridge inverter circuit, power supply circuits, discharge circuit, bypass circuit and the controller of electrical connection based on H bridge cascade connection type SVG power cell circuit, wherein,
Described H bridge inverter circuit is used for generating reactive power;
Described power supply circuits are used for obtaining electric energy from bus, provide described H bridge inverter circuit power tube to drive and the required electric energy of described controller work;
Described discharge circuit is for the capacitance voltage of adjusting described power cell circuit;
Described bypass circuit is electrically connected the interchange port of described H bridge inverter circuit, is used for realizing the Redundant Control of SVG;
Controller for the direct voltage of the described power supply circuits of sampling, is controlled H bridge inverter circuit, described discharge circuit and described bypass circuit.
Further, described H bridge inverter circuit comprises that IGBT pipe T1 and IGBT pipe T2 consist of a brachium pontis of H bridge inverter circuit, IGBT pipe T3 and IGBT pipe T4 consist of another brachium pontis of H bridge inverter circuit, and the buffer capacitor C3 that is in parallel with brachium pontis that IGBT pipe T1 and IGBT pipe T2 consist of, the buffer capacitor C2 that the brachium pontis that consists of with IGBT pipe T3 and IGBT pipe T4 is in parallel.
Further, described power supply circuits, comprise direct voltage Support Capacitor C4, C5, the C6 of three parallel connections and be connected in parallel on respectively grading resistor R2, R3 and the DC/DC power supply at three electric capacity two ends, the equiva lent impedance resistance of wherein said DC/DC power supply equates with the resistance of grading resistor R2 and R3.
In an implementation, described discharge circuit is made of a discharge power switch T5 and a discharge resistance R4 series connection.
Further; described bypass circuit; comprise thyristor Q1, the Q2 of two reverse parallel connections, the buffer circuit that is connected in the thyristor two ends in parallel and BOD protective circuit; wherein thyristor Q1, the Q2 of two reverse parallel connections link to each other with the port that the exchanges H bridge inverter circuit; buffer circuit is made of the capacitor C 1 and the R1 that are connected in series, and the negative electrode of thyristor Q1, Q2 connects the BOD protective circuit.
Preferably, the described DC/DC power supply Switching Power Supply that is constant-impedance.
The utility model is based on H bridge cascade connection type SVG power cell circuit:
1, the self-powered electric capacity of H bridge power unit circuit is got energy;
2, discharge mode is adopted in the balanced control of the direct voltage of H bridge power unit;
3, bypass circuit is realized the Redundant Control mode of SVG device, increases reliability;
4, power cell and master control system adopt optical fiber communication, solve isolating problem and interference problem between the strong and weak electricity;
5, the high pressure of power cell isolation.
Description of drawings
Fig. 1 is that the utility model is based on the block diagram of H bridge cascade connection type SVG power cell circuit embodiments;
Fig. 2 is that the utility model is based on the electrical block diagram of H bridge cascade connection type SVG power cell circuit embodiments;
Fig. 3 is the utility model is got the energy circuit based on the electric capacity of H bridge cascade connection type SVG power cell circuit embodiments structural representation;
Fig. 4 is that the utility model is based on the structural representation of the BOD protective circuit of H bridge cascade connection type SVG power cell circuit embodiments.
Embodiment
Below in conjunction with Figure of description the utility model is further described.
As shown in Figure 1, the utility model comprises H bridge inverter circuit 1, power supply circuits 2, discharge circuit 3, bypass circuit 4 and the controller 5 of electrical connection based on H bridge cascade connection type SVG power cell circuit, wherein,
Described H bridge inverter circuit is used for generating reactive power;
Described power supply circuits are used for obtaining electric energy from bus, provide described H bridge inverter circuit power tube to drive and the required electric energy of described controller work;
Described discharge circuit is for the capacitance voltage of adjusting described power cell circuit;
Described bypass circuit is electrically connected the interchange port of described H bridge inverter circuit, is used for realizing the Redundant Control of SVG;
Controller for the direct voltage of the described power supply circuits of sampling, is controlled H bridge inverter circuit, described discharge circuit and described bypass circuit.
In the H bridge inverter circuit, during when the active shutoff of IGBT pipe and at diode reverse recovery, because di/dt is very high, loop inductance can induce the switch overvoltage in IGBT pipe and diode.This effect is so that turn-off power loss increases, and the voltage stress of power semiconductor also increases thereupon.Therefore, in the current transformer that adopts hard switching, the total inductance of commutation circuit should be as much as possible little, particularly importantly notes keeping the inductance in dc bus loop as much as possible little.In order to reduce the stray inductance value in dc bus loop, adopt the copper bar of layered laminate to connect direct voltage Support Capacitor and power model, this class formation can be reduced to the inductance of copper bar the scope of 25～50nH, but these inductance are still influential to power model, can further reduce by the buffer circuits such as C in parallel, RC or RCD between the DC loop terminal of power model.In most of the cases, a simple C buffer circuit that is made of thin-film capacitor is just enough, and capacitance is between 0.1-2uF.
As shown in Figure 2, the present embodiment by shunt capacitance C2 and C3 as buffer circuit.Described H bridge inverter circuit 1 comprises that IGBT pipe T1 and IGBT pipe T2 consist of a brachium pontis of H bridge inverter circuit, IGBT pipe T3 and IGBT pipe T4 consist of another brachium pontis of H bridge inverter circuit, and the buffer capacitor C3 that is in parallel with brachium pontis that IGBT pipe T1 and IGBT pipe T2 consist of, the buffer capacitor C2 that the brachium pontis that consists of with IGBT pipe T3 and IGBT pipe T4 is in parallel, four IGBT pipes consist of the contribution module of H bridge inverter circuit, the C3 circuit is the absorbing circuit of T1 and T2, and the C2 circuit is the absorbing circuit of T3 and T4.
As shown in Figure 2, described power supply circuits 2, comprise direct voltage Support Capacitor C4, C5, the C6 of three parallel connections and be connected in parallel on respectively grading resistor R2, R3 and the DC/DC power supply at three electric capacity two ends, the equiva lent impedance resistance of wherein said DC/DC power supply equates with the resistance of grading resistor R2 and R3.Described DC/DC power supply is the Switching Power Supply of constant-impedance, and the equiva lent impedance resistance of Switching Power Supply equates with the resistance of grading resistor R2 and R3, and this has guaranteed all pressures of series capacitor C4, C5 and C6.The driving power of each power switch of H bridge inverter circuit and the power supply of controller are to be provided by the DC/DC Switching Power Supply.
Described discharge circuit 3 is made of a discharge power switch T5 and a discharge resistance R4 series connection.It is to be composed in series by IGBT pipe T5 and discharge resistance R4, and discharge circuit and direct voltage Support Capacitor are in parallel.Controller is regulated the equivalent resistance that is parallel to direct voltage Support Capacitor two ends by the turn-on and turn-off of PWM modulation strategy power ratio control switch T5, realizes the equilibrium control to H bridge power unit capacitance voltage.
Shown in Fig. 2-4; described bypass circuit 4; comprise thyristor Q1, the Q2 of two reverse parallel connections, the buffer circuit that is connected in the thyristor two ends in parallel and BOD protective circuit; wherein thyristor Q1, the Q2 of two reverse parallel connections link to each other with the port that the exchanges H bridge inverter circuit; buffer circuit is made of the capacitor C 1 and the R1 that are connected in series, and the negative electrode of thyristor Q1, Q2 connects the BOD protective circuit.When the H bridge inverter circuit breaks down, send instruction and make corresponding shunting device action, the action of controller control bypass circuit, interchange port phase short circuit with the H bridge inverter circuit, output and circuit with the fault power unit disconnects simultaneously, and two unit that will be adjacent with the fault power unit couple together, and effectively the fault power unit are separated from circuit, and then SVG can continue operation.Can realize the Redundant Control of SVG device.
As shown in Figure 2, described controller, the direct voltage of sampling Support Capacitor, and controlled discharge circuit, H bridge inverter circuit and bypass circuit, the power supply of controller is got and can be provided by circuit by electric capacity, and SVG master controller and power cell controller adopt optical fiber to communicate.
As shown in Figure 4; described BOD excess voltage protection, with a pair of anti-parallel thyristor Q1 of BOD element protection, a Q2, BOD is serially connected in the middle of the bridge circuit of D42, D43, D44, D45 composition; no matter the terminal voltage on Q1, the Q2 is positive and negative like this, BOD can work.If the triggered as normal passage of thyristor breaks down in thyristor is opened the stage; in the time of can not producing thyristor triggering impulse; as long as the forward voltage at thyristor two ends is greater than the operating value of excess voltage protection; then excess voltage protection (BOD triggering) is incited somebody to action in support trigger port; send trigger impulse to thyristor, the conducting thyristor.Electric current sealed in the gate pole amplifying circuit of Q1 when diode D47 was used for preventing the BOD action, and electric current sealed in the gate pole amplifying circuit of Q2 when diode D48 was used for preventing the BOD action.Above; it only is preferred embodiment of the present utility model; but protection range of the present utility model is not limited to this; anyly be familiar with those skilled in the art in the technical scope that the utility model discloses; the variation that can expect easily or replacement all should be encompassed within the protection range of the present utility model.Therefore, protection range of the present utility model should be as the criterion with the protection range that claim was defined.
Claims (6)
1. one kind based on H bridge cascade connection type SVG power cell circuit, it is characterized in that: comprise H bridge inverter circuit, power supply circuits, discharge circuit, bypass circuit and the controller of electrical connection, wherein,
Described H bridge inverter circuit is used for generating reactive power;
Described power supply circuits are used for obtaining electric energy from bus, provide described H bridge inverter circuit power tube to drive and the required electric energy of described controller work;
Described discharge circuit is for the capacitance voltage of adjusting described power cell circuit;
Described bypass circuit is electrically connected the interchange port of described H bridge inverter circuit, is used for realizing the Redundant Control of SVG;
Controller for the direct voltage of the described power supply circuits of sampling, is controlled H bridge inverter circuit, described discharge circuit and described bypass circuit.
2. according to claim 1 based on H bridge cascade connection type SVG power cell circuit, it is characterized in that: described H bridge inverter circuit comprises that IGBT pipe T1 and IGBT pipe T2 consist of a brachium pontis of H bridge inverter circuit, IGBT pipe T3 and IGBT pipe T4 consist of another brachium pontis of H bridge inverter circuit, and the buffer capacitor C3 that is in parallel with brachium pontis that IGBT pipe T1 and IGBT pipe T2 consist of, the buffer capacitor C2 that the brachium pontis that consists of with IGBT pipe T3 and IGBT pipe T4 is in parallel.
3. according to claim 1 based on H bridge cascade connection type SVG power cell circuit, it is characterized in that: described power supply circuits, comprise direct voltage Support Capacitor C4, C5, the C6 of three parallel connections and be connected in parallel on respectively grading resistor R2, R3 and the DC/DC power supply at three electric capacity two ends, the equiva lent impedance resistance of wherein said DC/DC power supply equates with the resistance of grading resistor R2 and R3.
4. according to claim 1 based on H bridge cascade connection type SVG power cell circuit, it is characterized in that: described discharge circuit is made of a discharge power switch T5 and a discharge resistance R4 series connection.
5. according to claim 1 based on H bridge cascade connection type SVG power cell circuit; it is characterized in that: described bypass circuit; comprise thyristor Q1, the Q2 of two reverse parallel connections, the buffer circuit that is connected in the thyristor two ends in parallel and BOD protective circuit; wherein thyristor Q1, the Q2 of two reverse parallel connections link to each other with the port that the exchanges H bridge inverter circuit; buffer circuit is made of the capacitor C 1 and the R1 that are connected in series, and the negative electrode of thyristor Q1, Q2 connects the BOD protective circuit.
6. according to claim 3 based on H bridge cascade connection type SVG power cell circuit, it is characterized in that: described DC/DC power supply is the Switching Power Supply of constant-impedance.
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| Application Number | Priority Date | Filing Date | Title |
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| CN2012202576892U CN202749820U (en) | 2012-06-01 | 2012-06-01 | H-bridge cascaded SVG power unit circuit |
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| CN2012202576892U CN202749820U (en) | 2012-06-01 | 2012-06-01 | H-bridge cascaded SVG power unit circuit |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103401253A (en) * | 2013-08-14 | 2013-11-20 | 深圳市英威腾电气股份有限公司 | SVG power unit circuit, chained SVG power unit circuit and static voltage-sharing method |
| CN104049146A (en) * | 2014-06-30 | 2014-09-17 | 北京四方继保自动化股份有限公司 | Method for determining static equalizing resistance value of power module of chained multi-level converter |
| CN104079154A (en) * | 2014-07-15 | 2014-10-01 | 北京利德华福电气技术有限公司 | Current-sharing bypass circuit of power unit of high-voltage inverter |
| CN105337478A (en) * | 2015-11-16 | 2016-02-17 | 北京机械设备研究所 | Anti-parallel thyristor drive circuit for pulse width modulation voltage |
| CN106229996A (en) * | 2016-08-16 | 2016-12-14 | 株洲变流技术国家工程研究中心有限公司 | A kind of system realizing the operation of SVG device multi-machine parallel connection and control method thereof |
| CN106347170A (en) * | 2016-10-19 | 2017-01-25 | 株洲中车时代电气股份有限公司 | Active discharging circuit of motor controller for electric automobile |
| CN107069724A (en) * | 2016-12-19 | 2017-08-18 | 东北电力大学 | H bridge cascade connection types SVG parallel connection harmonic circulating current suppressing methods |
| CN114069694A (en) * | 2021-11-02 | 2022-02-18 | 北京动力源科技股份有限公司 | Method for reducing loop inductance of multi-phase variable frequency/fixed frequency parallel multi-module unit |
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2012
- 2012-06-01 CN CN2012202576892U patent/CN202749820U/en not_active Expired - Fee Related
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103401253A (en) * | 2013-08-14 | 2013-11-20 | 深圳市英威腾电气股份有限公司 | SVG power unit circuit, chained SVG power unit circuit and static voltage-sharing method |
| CN103401253B (en) * | 2013-08-14 | 2016-02-03 | 深圳市英威腾电气股份有限公司 | SVG power cell circuit, chain type SVG power cell circuit and static state voltage equipoise method |
| CN104049146A (en) * | 2014-06-30 | 2014-09-17 | 北京四方继保自动化股份有限公司 | Method for determining static equalizing resistance value of power module of chained multi-level converter |
| CN104079154A (en) * | 2014-07-15 | 2014-10-01 | 北京利德华福电气技术有限公司 | Current-sharing bypass circuit of power unit of high-voltage inverter |
| CN105337478A (en) * | 2015-11-16 | 2016-02-17 | 北京机械设备研究所 | Anti-parallel thyristor drive circuit for pulse width modulation voltage |
| CN106229996A (en) * | 2016-08-16 | 2016-12-14 | 株洲变流技术国家工程研究中心有限公司 | A kind of system realizing the operation of SVG device multi-machine parallel connection and control method thereof |
| CN106229996B (en) * | 2016-08-16 | 2019-01-22 | 株洲变流技术国家工程研究中心有限公司 | A kind of system and its control method for realizing the operation of SVG device multi-machine parallel connection |
| CN106347170A (en) * | 2016-10-19 | 2017-01-25 | 株洲中车时代电气股份有限公司 | Active discharging circuit of motor controller for electric automobile |
| CN107069724A (en) * | 2016-12-19 | 2017-08-18 | 东北电力大学 | H bridge cascade connection types SVG parallel connection harmonic circulating current suppressing methods |
| CN107069724B (en) * | 2016-12-19 | 2020-02-14 | 东北电力大学 | H-bridge cascade SVG parallel harmonic circulating current suppression method |
| CN114069694A (en) * | 2021-11-02 | 2022-02-18 | 北京动力源科技股份有限公司 | Method for reducing loop inductance of multi-phase variable frequency/fixed frequency parallel multi-module unit |
| CN114069694B (en) * | 2021-11-02 | 2024-03-22 | 北京动力源科技股份有限公司 | Method for reducing loop inductance of multiphase variable frequency/fixed frequency parallel multi-module unit |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| EE01 | Entry into force of recordation of patent licensing contract |
Assignee: Nanjing, sky electrical engineering Technology Co., Ltd. of middle smelting China Assignor: Zhongye Huatian Engineering Technology Co., Ltd. Contract record no.: 2015990000111 Denomination of utility model: H-bridge cascaded SVG power unit circuit Granted publication date: 20130220 License type: Exclusive License Record date: 20150318 |
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| LICC | Enforcement, change and cancellation of record of contracts on the licence for exploitation of a patent or utility model | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20130220 Termination date: 20190601 |