CN102324755B - Low-voltage ride through control method and device for doubly-fed wind power generating system - Google Patents

Low-voltage ride through control method and device for doubly-fed wind power generating system Download PDF

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CN102324755B
CN102324755B CN2011103059639A CN201110305963A CN102324755B CN 102324755 B CN102324755 B CN 102324755B CN 2011103059639 A CN2011103059639 A CN 2011103059639A CN 201110305963 A CN201110305963 A CN 201110305963A CN 102324755 B CN102324755 B CN 102324755B
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circuit
electric machine
release
voltage
low
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CN102324755A (en
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张晓�
谭国俊
邓先明
甄文欢
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China Mining Drives & Automation Co ltd
China University of Mining and Technology CUMT
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China Mining Drives & Automation Co ltd
China University of Mining and Technology CUMT
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    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00Energy generation through renewable energy sources
    • Y02E10/70Wind energy
    • Y02E10/76Power conversion electric or electronic aspects

Abstract

The invention discloses a low-voltage ride through control method and a low-voltage ride through control device for a doubly-fed wind power generating system. The device comprises a reversible power converter, a motor controller, a signal detection circuit and a crowbar protection circuit. The crowbar protection circuit consists of a three-phase uncontrolled bridge rectifier, a primary release circuit and a secondary release circuit. When a power grid has a low-voltage failure, the reversible power converter stops working, the primary and secondary release circuits in the crowbar protection circuit are switched on at the same time and work in parallel to rapidly release transient impact current in a rotor winding of a doubly-fed motor; when the current of a rotor attenuated to a rated value, the secondary release circuit stops working, and the primary release circuit is still switched on to release the transient current in the rotor wining; and after the low-voltage failure of the power grid is eliminated to recover the voltage of the power grid, the reversible power converter restarts working, and the crowbar protection circuit completely stops working. By the method and the device, high ride through capability and good effects are ensured, the time of a transient process for low-voltage ride through can be shortened, the voltage recovery of the power grid can be accelerated and secondary over-current can be effectively prevented.

Description

The low voltage traversing control method of dual feedback wind power generation system and device
Technical field
The present invention relates to wind power generation field, especially a kind of low voltage traversing control method of dual feedback wind power generation system and device.
Background technology
In recent years, along with the development of wind generating technology, the installed capacity of wind power generation is risen year by year, electrical network break down cause voltage to fall after, if wind turbine generator all off-the-line will be brought the transient state instability of electric power system, and may cause part even system to be paralysed comprehensively.Therefore electric power system has proposed series of requirements to the operation of wind power plant, comprise the electric network fault ride-through capability, be that blower fan is incorporated into the power networks point voltage when falling, blower fan can keep being incorporated into the power networks, even provide certain reactive power to recover to support line voltage to electrical network, recover normal up to line voltage, thus " passing through " this low-voltage time.
In the double-fed wind-driven power generation system, because the stator of double feedback electric engine directly is connected with electrical network, therefore when falling, line voltage can cause its stator terminal voltage to fall, because stator magnetic linkage can not suddenly change, cause containing in the stator magnetic linkage DC component, asymmetric line voltage falls also negative sequence component can occur.Because the rotating speed that is incorporated into the power networks of the double feedback electric engine in the dual feedback wind power generation system is usually than higher, this high rotational speed is for the flip-flop in the stator magnetic linkage and negative phase-sequence composition, all have bigger revolutional slip, thereby in the double fed electric machine rotor circuit, generate bigger rotor voltage and rotor current.Higher transient current amount and voltage have constituted threat to the safe operation of semiconductor device in the rotor current transformer in the rotor circuit, can cause the action of rotor-side converter protective circuit when serious even burn out current transformer.For during electric network fault, the protection rotor-side converter makes the double-fed wind power generator group have low voltage ride-through capability, and commercial double-fed wind power generator group mostly is equipped with crowbar circuit.
There is defective in the crow bar protective circuit of using in low-voltage is passed through based on IGBT at present: (1) capacity is less can not to adapt to big capacity dual feedback wind power generation system, and (2) cause problems such as DC bus-bar voltage overvoltage and secondary overcurrent easily.
Summary of the invention
Technical problem: the objective of the invention is to overcome the weak point in the prior art, low voltage traversing control method and the device of the dual feedback wind power generation system of provide that a kind of simple in structure, capacity is big, stable performance, control are effective.
Technical scheme: the low voltage traversing control method of dual feedback wind power generation system of the present invention:
When electrical network generation low voltage failure, by signal deteching circuit detected low voltage failure signal is passed to electric machine controller, electric machine controller sends control command after receiving signal, reversible power inverter is quit work, send signal simultaneously and open the crow bar protective circuit, the main release circuit in the crow bar protective circuit and auxiliary release circuit parallel operation discharge the transient state impulse current in the double fed electric machine rotor winding fast;
After signal deteching circuit detected rotor current and decays to rated value, electric machine controller sent signal and auxiliary release circuit in the crow bar protective circuit is turn-offed quit work, and the main circuit that discharges continues conducting and discharges transient current in the double fed electric machine rotor winding;
After low voltage failure of electric network excision voltage recovered, electric machine controller sent control signal, restarts reversible power inverter work, and the while electric machine controller sends control signal quits work the crow bar protective circuit fully.
The low-voltage of the dual feedback wind power generation system of realization said method is passed through control device, comprise three phase network, double fed electric machine rotor winding, reversible power inverter, crow bar protective circuit, signal deteching circuit and electric machine controller, reversible power inverter pusher side three-phase terminal is connected with the three-phase terminal of double fed electric machine rotor winding, and reversible power inverter net side three-phase terminal is connected with three phase network; The crow bar protective circuit is connected between the connecting line of double fed electric machine rotor winding and reversible power inverter; Described reversible power inverter, crow bar protective circuit and signal deteching circuit are connected with electric machine controller respectively, it is characterized in that: described crow bar protective circuit by three-phase not the controlled bridge-type rectifier, main discharge circuit and the auxiliary circuit that discharges is formed, main discharge circuit and auxiliary discharge after the circuit parallel connection with three-phase not the controlled bridge-type rectifier contact; The main circuit that discharges is made of fly-wheel diode, insulated gate bipolar transistor IGBT, resistance and electric capacity respectively with the auxiliary circuit that discharges, the anode of fly-wheel diode is connected with the emitter of insulated gate bipolar transistor IGBT, the negative electrode of fly-wheel diode is connected with the collector electrode of insulated gate bipolar transistor IGBT, insulated gate bipolar transistor IGBT and RCD absorb circuit and form parallel circuits, and this parallel circuits is connected with release resistance.
Beneficial effect: the present invention adopts the crow bar protective circuit to realize the control that low-voltage is passed through, the crow bar protective circuit is discharged circuit and is assisted the release circuit to compose in parallel by main, can discharge very big transient current, this low-voltage traversing device is applicable to big capacity dual feedback wind power generation system, and it is not easy to damage; During low-voltage was passed through, the control equivalence discharged the resistance size of resistance, has protected reversible power inverter well on the one hand, shortens settling time on the other hand and has accelerated the line voltage recovery, has effectively prevented the secondary overcurrent simultaneously.Therefore, the ride-through capability of low-voltage traversing device of the present invention is strong, effective.
Major advantage of the present invention is as follows:
1, comprise the crow bar protective circuit in the low-voltage traversing device of the present invention, main circuit and the auxiliary circuit parallel operation that discharges of discharging in the crow bar protective circuit possesses the ability that discharges big transient current.Therefore, this low-voltage traversing device can be applicable to that the low-voltage of big capacity dual feedback wind power generation system passes through control;
2, pass through the initial stage in low-voltage, main in the crow bar protective circuit discharges circuit and auxiliary to discharge circuit open-minded simultaneously, parallel operation, and it is little that equivalence discharges resistance, the maximum peak voltage of restrict rotor winding well, thus protect reversible power inverter.Pass through the later stage in low-voltage, the auxiliary discharge road in the crow bar protective circuit quits work, and the main circuit that discharges works on, and it is big that equivalence discharges resistance, can shorten settling time, can prevent the secondary overcurrent effectively simultaneously;
3, the absorption circuit in the crow bar protective circuit can suppress well because IGBT is protected in overcurrent and the overvoltage that the IGBT switch causes.
Description of drawings
Fig. 1 passes through control system figure for double-fed generator low-voltage of the present invention.
Fig. 2 is crow bar protective circuit figure of the present invention.
Among the figure: the 1-three phase network; The 2-switch that is incorporated into the power networks; The 3-wind energy conversion system; The 4-double feedback electric engine; 5-double feedback electric engine stator winding; 6-double fed electric machine rotor winding; The reversible power inverter of 7-; The 8-electric machine controller; The 9-signal deteching circuit; 10-crow bar protective circuit; The UR-three-phase is the controlled bridge-type rectifier not; Resistance R 1; Resistance R 2; Resistance R 3; Resistance R 4; Sustained diode 1; Sustained diode 2; Sustained diode 3; Sustained diode 4; Insulated gate bipolar transistor IGBT 1; Insulated gate bipolar transistor IGBT 2; Capacitor C 1; Capacitor C 2.
Embodiment
Below in conjunction with accompanying drawing one embodiment of the present of invention are further described:
As shown in Figure 1; the low voltage traversing control method of dual feedback wind power generation system of the present invention; when electrical network generation low voltage failure; signal deteching circuit 9 passes to electric machine controller 8 with detected low voltage failure signal; electric machine controller 8 receives and sends control command behind this signal reversible power inverter 7 is quit work; sending signal simultaneously opens the main release circuit in the crow bar protective circuit 10 and assists the release circuit; discharge the transient state impulse current in the double fed electric machine rotor winding 6 fast; this moment, the main circuit that discharges discharged the circuit parallel operation with assisting, and the equivalence in the crow bar protective circuit 10 discharges the maximum peak voltage of the less restrict rotor well of resistance winding.Transient current in the rotor winding can be decayed according to index law from bigger amplitude; after signal deteching circuit 9 detects rotor current and decays to rated value; electric machine controller 8 sends signal again quits work the auxiliary release circuit in the crow bar protective circuit 10; the main transient current that discharges in the circuit continuation conducting release double fed electric machine rotor winding 6; it is bigger that equivalence in the crow bar protective circuit 10 at this moment discharges resistance; settling time can be shortened; be conducive to line voltage and recover, can prevent the secondary overcurrent well simultaneously.After low voltage failure of electric network excision voltage recovered, electric machine controller 8 sent control signal and restarts reversible power inverter 7 work, sends control signal simultaneously crow bar protective circuit 10 is quit work fully.
Concrete calculation of parameter:
Model machine parameter such as the following table implemented:
Motor rated capacity (MW) 1.5
Stator rated voltage (V) 690
Rated frequency (Hz) 50
Number of pole-pairs 2
The rotor turn ratio 1:3
Stator rated current (A) 1105
Rotor rated current (A) 453
Rotor resistance (Ω) 0.018
Rotor leakage inductance (H) 0.00013
Release resistance R 1 in the crow bar protective circuit, the calculating of R2:
When release resistance was too small, the rotor transient current can be very big, may damage motor, and therefore, the motor transient current need be less than safe current I Rsafe, the Generally Recognized as safe electric current can be got 2 times rated current.The minimum of crow bar protective circuit discharges resistance calculations:
In the formula E RmaxMaximum induced potential when being low voltage failure in the rotor winding, x R σBe rotor winding leakage reactance, r rIt is the rotor winding resistance.When the electrical network fault that is short-circuited, when double feedback electric engine works in 1.3 times same leg speed, the rotor winding will be responded to maximum electromotive force, be 1.3 times stator rated voltage.
During model machine generation low voltage failure, the maximum electromotive force of rotor winding induction is 518V, and the rotor leakage reactance is 0.053 ohm, and the minimum that can calculate the crow bar protective circuit discharges resistance and is:
Therefore, the release resistance R 1 in the crow bar protective circuit and R2 equate that the minimum that equals 2 times discharges resistance value, that is: R1=R2=1.1 Ω.
Other device parameters: IGBT selects 3300V, 800A; R3=R4=10 Ω; C1=C2=4.7 μ F
The present invention realizes that the low-voltage of the dual feedback wind power generation system of said method passes through control device, comprises three phase network 1, the switch 2 that is incorporated into the power networks, wind energy conversion system 3, double feedback electric engine 4, double feedback electric engine stator winding 5, double fed electric machine rotor winding 6, reversible power inverter 7, electric machine controller 8, signal deteching circuit 9 and crow bar protective circuit 10.Reversible power inverter 7 pusher side three-phase terminals are connected with the three-phase terminal of double fed electric machine rotor winding 6, and reversible power inverter 7 net side three-phase terminals are connected with three phase network 1; Crow bar protective circuit 10 is connected between the connecting line of double fed electric machine rotor winding 6 and reversible power inverter 7; Described reversible power inverter 7, crow bar protective circuit 10 and signal deteching circuit 9 are connected with electric machine controller 8 respectively, by electric machine controller 8 control reversible power inverter 7, crow bar protective circuit 10 and signal deteching circuits 9.Described crow bar protective circuit 10 by three-phase not controlled bridge-type rectifier UR, main discharge circuit and the auxiliary circuit that discharges is formed, main discharge circuit and auxiliary discharge after the circuit parallel connection with three-phase not the controlled bridge-type rectifier contact; The main circuit that discharges is made of fly-wheel diode, insulated gate bipolar transistor IGBT, resistance and electric capacity respectively with the auxiliary circuit that discharges, the anode of fly-wheel diode is connected with the emitter of insulated gate bipolar transistor IGBT, the negative electrode of fly-wheel diode is connected with the collector electrode of insulated gate bipolar transistor IGBT, insulated gate bipolar transistor IGBT and RCD absorb circuit and form parallel circuits, and this parallel circuits is connected with release resistance.Device model and the annexation of main release circuit and auxiliary release circuit are identical.The negative electrode of sustained diode 1 is connected with the collector electrode of insulated gate bipolar transistor IGBT 1, the anode of sustained diode 1 is connected with the emitter of insulated gate bipolar transistor IGBT 1, reverse parallel connection is realized the protection to insulated gate bipolar transistor IGBT 1, connect with capacitor C 1 and constitute RCD absorption circuit in the shunt circuit of resistance R 3, sustained diode 3, insulated gate bipolar transistor IGBT 1 absorbs circuit with this RCD and forms parallel circuits, and this parallel circuits is connected with release resistance R 1 and constituted the main circuit that discharges; The negative electrode of sustained diode 2 is connected with the collector electrode of insulated gate bipolar transistor IGBT 2; the anode of sustained diode 2 is connected with the emitter of insulated gate bipolar transistor IGBT 2; reverse parallel connection is realized the protection to insulated gate bipolar transistor IGBT 2; connect with capacitor C 2 and constitute RCD absorption circuit in the shunt circuit of resistance R 4, sustained diode 4; insulated gate bipolar transistor IGBT 2 absorbs circuit with this RCD and forms parallel circuits, and this parallel circuits is connected with release resistance R 2 and constituted the auxiliary circuit that discharges.

Claims (2)

1. the low voltage traversing control method of a dual feedback wind power generation system is characterized in that:
When electrical network generation low voltage failure, by signal deteching circuit (9) detected low voltage failure signal is passed to electric machine controller (8), electric machine controller (8) sends control command after receiving signal, reversible power inverter (7) is quit work, while electric machine controller (8) sends signal and opens crow bar protective circuit (10), and the main release circuit in the crow bar protective circuit (10) and auxiliary release circuit parallel operation discharge the transient state impulse current in the double fed electric machine rotor winding (6) fast;
After signal deteching circuit (9) detects rotor current and decays to rated value, electric machine controller (8) sends signal makes the auxiliary release circuit shutoff in the crow bar protective circuit (10) quit work the main transient current that discharges in the circuit continuation conducting release double fed electric machine rotor winding (6);
After low voltage failure of electric network excision voltage recovered, electric machine controller (8) sent control signal, restarted reversible power inverter (7) work, and while electric machine controller (8) sends control signal quits work crow bar protective circuit (10) fully.
2, a kind of low-voltage of the dual feedback wind power generation system of the described method of claim 1 that realizes is passed through control device, comprise three phase network (1), double fed electric machine rotor winding (6), reversible power inverter (7), crow bar protective circuit (10), signal deteching circuit (9) and electric machine controller (8), reversible power inverter (7) pusher side three-phase terminal is connected with the three-phase terminal of double fed electric machine rotor winding (6), and reversible power inverter (7) net side three-phase terminal is connected with three phase network (1); Crow bar protective circuit (10) is connected between the connecting line of double fed electric machine rotor winding (6) and reversible power inverter (7); Described reversible power inverter (7), crow bar protective circuit (10) and signal deteching circuit (9) are connected with electric machine controller (8) respectively, it is characterized in that: described crow bar protective circuit (10) by three-phase not controlled bridge-type rectifier (UR), main discharge circuit and the auxiliary circuit that discharges is formed, main discharge after circuit and the parallel connection of auxiliary release circuit with three-phase not the controlled bridge-type rectifier connect; The main circuit that discharges is made of fly-wheel diode, insulated gate bipolar transistor IGBT, resistance and electric capacity respectively with the auxiliary circuit that discharges, the anode of fly-wheel diode is connected with the emitter of insulated gate bipolar transistor IGBT, the negative electrode of fly-wheel diode is connected with the collector electrode of insulated gate bipolar transistor IGBT, insulated gate bipolar transistor IGBT and RCD absorb circuit and form parallel circuits, and this parallel circuits is connected with release resistance.
CN2011103059639A 2011-10-11 2011-10-11 Low-voltage ride through control method and device for doubly-fed wind power generating system Active CN102324755B (en)

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102412597A (en) * 2012-02-07 2012-04-11 徐州中矿大传动与自动化有限公司 Low voltage ride through control method and device for a double-fed wind power generation system
CN105186559B (en) * 2015-08-31 2017-09-29 国网江苏省电力公司盐城供电公司 A kind of double-fed wind power generator group low voltage crossing circuit and its control method
CN108023470B (en) * 2017-12-29 2020-11-10 天津瑞能电气有限公司 Crowbar protection circuit for double-fed power generation system
CN110082613A (en) * 2019-05-27 2019-08-02 上海电气风电集团有限公司 A kind of main circuit of wind power converter connection state detection system and detection method

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Publication number Priority date Publication date Assignee Title
CN101895126A (en) * 2009-05-20 2010-11-24 天津瑞能电气有限公司 Low voltage ride through control circuit of doubly-fed variable-speed constant-frequency wind power generator unit
CN101917156A (en) * 2010-08-30 2010-12-15 南车株洲电力机车研究所有限公司 Method and device for protecting wind generating set during electric network voltage dip in short time

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CN101741100A (en) * 2010-01-11 2010-06-16 华锐风电科技(集团)股份有限公司 Low voltage ride-through control scheme

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101895126A (en) * 2009-05-20 2010-11-24 天津瑞能电气有限公司 Low voltage ride through control circuit of doubly-fed variable-speed constant-frequency wind power generator unit
CN101917156A (en) * 2010-08-30 2010-12-15 南车株洲电力机车研究所有限公司 Method and device for protecting wind generating set during electric network voltage dip in short time

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