CN209072089U - A kind of paddle change system of wind turbines high voltage crossing controller - Google Patents
A kind of paddle change system of wind turbines high voltage crossing controller Download PDFInfo
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- CN209072089U CN209072089U CN201822237623.7U CN201822237623U CN209072089U CN 209072089 U CN209072089 U CN 209072089U CN 201822237623 U CN201822237623 U CN 201822237623U CN 209072089 U CN209072089 U CN 209072089U
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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
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/70—Wind energy
- Y02E10/76—Power conversion electric or electronic aspects
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Abstract
The utility model provides a kind of paddle change system of wind turbines high voltage crossing controller, front end by being located at charging resistor in the rectification circuit of pitch-controlled system power supply module driving power increases thermistor of having connected, and access/fault control is carried out to thermistor by switching relay, and pass through the voltage effective value of the exchange end voltage collector acquisition monitoring externally input three-phase alternating-current supply of pitch-controlled system power supply module driving power, and then switching relay is controlled according to the voltage condition of three-phase alternating-current supply using exchange end voltage comparator, access/Short-circuit Working Condition of thermistor is switched over, combine by driving power in pitch-controlled system, backup power supply and stand-by power source manage the original low-voltage variation function of circuit, realize the high voltage crossing control to Wind turbines pitch motor drive module, technical thought is ingenious, system changes Cause this low with technical difficulty, the high voltage crossing control for pitch motor drive module in Wind turbines provides new technical thought.
Description
Technical field
The utility model relates to Control Technology of Wind Power Generation System field, in particular to a kind of paddle change system of wind turbines is high
Voltage ride-through controller.
Background technique
In Wind turbines, pitch-controlled system power supply module driving power is the important component of pitch-controlled system.Such as Fig. 1 institute
Show, pitch-controlled system power supply module driving power mainly includes rectification circuit, filter-capacitor circuit, backup power supply and standby electricity
Power management circuits, major function are that external three-phase alternating current end 400V alternating voltage is become the straight of pulsation by rectification circuit
Galvanic electricity, then 560V DC power supply is obtained after filtering out the alternating component in Rectified alternating current with filter capacitor, it is loaded into DC bus
On, 560V DC power supply is provided for pitch motor drive module；Meanwhile pitch-controlled system power supply module driving power also passes through standby
Electric power management circuit is responsible for carrying out backup power supply (super capacitor) charging and low-voltage variation management, and backup power supply manages circuit
It is exported according to backup power supply and pitch-controlled system power supply module driving power to the voltage at DC bus end, when backup power supply voltage is low
Stand-by power source manages circuit start charge function when limit value, is filled by pitch-controlled system power supply module driving power to backup power supply
Electricity, when making a clean sweep of the reasons such as electricity because of the exchange of external three phase mains causes driving power to export to DC bus end brownout, after
Stand-by power source manages circuit start boost function, is powered by backup power supply to DC bus end, so that DC bus end is boosted, with
Guarantee that pitch motor drive module operates normally, realizes low-voltage variation function.When opening major loop, bulky capacitor fills in order to prevent
Electricity and cause the excessive damage silicon stack of electric current, therefore be provided in the rectification circuit of pitch-controlled system power supply module driving power charging electricity
Resistance carries out current limliting, the pre-charge process after starting to filter capacitor, while precharge, to the voltage at DC bus end into
Row monitoring, after being precharged to DC bus-bar voltage and reaching 400 VDC, by design control circuit switching so that charging resistor quilt
Short circuit, and terminate the pre-charge process of current-limited startup, into normal operating condition, pitch motor drive module is powered.
As the continuous expansion of wind power plant scale and wind-power electricity generation capacity causes variable pitch system when electric network fault or disturbance
When the voltage of the external input three-phase alternating-current supply of system power supply module driving power increases suddenly, it will lead to DC bus-bar voltage
It is out-of-limit, thus pair and dc-link capacitance constitute a threat to, in some instances it may even be possible to will lead to serious chain reaction, influence pitch motor drive
The normal operation of dynamic model block.It is required based on safe and stable operation and control protection, many countries have formulated new interconnection technology rule
Fixed, in recent years, high voltage crossing is increasingly taken seriously, and China's national standard Wind turbines, which should meet high voltage crossing, to be wanted
Ask, when high voltage cascading failure through fault occurs, it is desirable that the various components of Wind turbines can defined voltage and when
Between should have the ability of not off-grid continuous operation in range, restored so that power can be fast implemented after voltage restores normal.It is right
In the pitch-controlled system of Wind turbines, it should also which design meets high voltage crossing requirement.
Therefore, it is necessary to the related circuit design of the pitch-controlled system power supply module driving power to Wind turbines be transformed it is excellent
Change so that the pitch motor drive module of Wind turbines has certain high voltage crossing ability, make it in electric network fault or
When disturbance causes voltage to increase suddenly, Wind turbines continual can be run, and completed network voltage and be soared to the normal mistake of recovery
The high voltage fail of journey is passed through.
Utility model content
Aiming at the above shortcomings existing in the prior art, the purpose of this utility model is to provide a kind of Wind turbines variable pitches
System high voltage traverse controller, with so that the pitch motor drive module of Wind turbines has high voltage fail and passes through energy
Power.
In order to achieve the above purposes, the technical solution adopted by the utility model is:
A kind of paddle change system of wind turbines high voltage crossing controller drives mould for the pitch motor for Wind turbines
Block executes high voltage crossing control, including pitch-controlled system power supply module driving power, the pitch-controlled system power supply mould group driving electricity
Source includes rectification circuit, filter-capacitor circuit, backup power supply and backup power supply management circuit, is arranged in the rectification circuit
There is charging resistor；It also connects front end in the rectification circuit of the pitch-controlled system power supply module driving power positioned at charging resistor
It is provided with thermistor；It further include exchange end voltage collector, exchange end voltage comparator and switching relay；The exchange end
Voltage collector is used to acquire the voltage effective value of the externally input three-phase alternating-current supply of pitch-controlled system power supply module driving power,
And the output end for exchanging end voltage collector is electrically connected to the comparison signal input terminal of exchange end voltage comparator；The exchange end
The reference voltage value of voltage comparator be high voltage crossing trigger voltage value, exchange end voltage comparator output end with cut
Change the control terminal electrical connection of relay；The switching relay is closed type relay, and the tip side for switching relay is in parallel
The both ends of thermistor in the rectification circuit.
It is preferably, hot in the rectification circuit in above-mentioned paddle change system of wind turbines high voltage crossing controller
Quick resistance is able to bear the DC voltage more than or equal to 170V, and resistance value isolation alternating current is capable of increasing when high voltage arrives
Net and DC bus.
In above-mentioned paddle change system of wind turbines high voltage crossing controller, preferably, the high voltage crossing touching
Send out 1.1 times that voltage value is the externally input three-phase alternating-current supply reference voltage virtual value of pitch-controlled system power supply module driving power
To 1.3 times.
Correspondingly, the utility model additionally provides a kind of paddle change system of wind turbines high voltage crossing control method；For this purpose,
The utility model uses the following technical solution:
Compared with the prior art, the utility model has the following beneficial effects:
The paddle change system of wind turbines high voltage crossing controller of the utility model, major design the improvement is that,
Increase thermistor of having connected positioned at the front end of charging resistor in the rectification circuit of pitch-controlled system power supply module driving power, and logical
It crosses switching relay and access/fault control is carried out to thermistor, and pass through exchange end voltage collector acquisition monitoring variable pitch system
The voltage effective value of the system externally input three-phase alternating-current supply of power supply module driving power, and then utilize exchange end voltage comparator
Switching relay is controlled according to the voltage condition of three-phase alternating-current supply to switch over access/Short-circuit Working Condition of thermistor, is joined
It closes and manages the original low-voltage variation function of circuit by driving power in pitch-controlled system, backup power supply and stand-by power source, realize pair
The high voltage crossing of Wind turbines pitch motor drive module controls, and technical thought is ingenious, system reform cost and technical difficulty
Low, the high voltage crossing control for pitch motor drive module in Wind turbines provides new technical thought.
Detailed description of the invention
Fig. 1 is the interlock circuit structural schematic diagram of pitch-controlled system power supply module driving power in the prior art.
Fig. 2 is a kind of structural schematic diagram of the utility model paddle change system of wind turbines high voltage crossing controller.
Fig. 3 is a kind of principle schematic diagram that stand-by power source manages circuit in pitch-controlled system.
Specific embodiment
As shown in Fig. 2, the utility model provides a kind of paddle change system of wind turbines high voltage crossing controller, for pair
High voltage crossing control is executed in the pitch motor drive module of Wind turbines, pitch-controlled system power supply mould group driving described in the system
Power supply includes rectification circuit, filter-capacitor circuit, backup power supply and backup power supply management circuit, is set in the rectification circuit
It is equipped with charging resistor；In addition, being located in the rectification circuit of the pitch-controlled system power supply module driving power as Curve guide impeller
The front end of charging resistor has also been arranged in series thermistor；Further include exchange end voltage collector, exchange end voltage comparator and
Switch relay；The exchange end voltage collector is for acquiring the externally input three-phase of pitch-controlled system power supply module driving power
The voltage effective value of AC power source, and the output end for exchanging end voltage collector is electrically connected to the comparison of exchange end voltage comparator
Signal input part；The reference voltage value of the exchange end voltage comparator is high voltage crossing trigger voltage value, exchanges end
The output end of voltage comparator is electrically connected with the control terminal of switching relay；The switching relay is closed type relay, and
The tip side of switching relay is connected in parallel on the both ends of thermistor in the rectification circuit.
In the paddle change system of wind turbines high voltage crossing controller of the utility model, the driving of pitch-controlled system power supply mould group
Original circuit, backup power supply and the backup power supply of power supply manage circuit, work all in accordance with the setting operating condition that has of pitch-controlled system
, especially backup power supply and backup power supply manage circuit, wear in the paddle change system of wind turbines high voltage of the utility model
Do not make design change for the two more in controller, it completely can be using existing backup power supply and backup power supply in pitch-controlled system
Manage circuit design.For example, backup power supply can be realized using super capacitor.Backup power supply manages circuit then can be using such as
Backup power supply commonly used in the prior art shown in Fig. 3 manages circuit, and UDC+ and UDC- indicate the positive and negative electrode of DC bus-bar voltage
Terminal；DC bus-bar voltage normal period, in charging control process, stand-by power source manages the upper tube of the IGBT half-bridge in circuit
Work, down tube do not work, and backup power supply Management Controller adjusts charging voltage and electric current by adjusting the duty ratio of pwm signal,
UDC+ is controlled to charge to backup battery (super capacitor)；And when DC bus-bar voltage is too low, stand-by power source manages in circuit
The upper tube of IGBT half-bridge does not work, down tube work, and backup power supply Management Controller is straight by adjusting the duty ratio control of pwm signal
Busbar voltage is flowed, between PWM high period, down tube conducting, external reactor energy storage, between PWM low period, down tube cut-off is external
After the voltage superposition of reactor voltage and battery, the positive terminal of superimposed voltage is connected to directly by the freewheeling diode in upper tube
The end UDC+ for flowing bus, so that DC bus-bar voltage be made to rise.
In the paddle change system of wind turbines high voltage crossing controller of the utility model, major design improvements exist
In the front end for being located at charging resistor in the rectification circuit of pitch-controlled system power supply module driving power increases temperature-sensitive electricity of having connected
Resistance, and access/fault control is carried out to thermistor by switching relay, and pass through exchange end voltage collector acquisition monitoring
The voltage effective value of the externally input three-phase alternating-current supply of pitch-controlled system power supply module driving power, and then utilize exchange end voltage
Comparator controls switching relay according to the voltage condition of three-phase alternating-current supply and cuts to access/Short-circuit Working Condition of thermistor
It changes, to execute the high voltage crossing control to the pitch motor drive module of Wind turbines.Its specific control mode is as follows:
Exchange externally input three intersection of end voltage collector real-time monitoring acquisition pitch-controlled system power supply module driving power
The voltage effective value in galvanic electricity source is transmitted to the comparison signal input terminal of exchange end voltage comparator, is compared by exchanging end voltage
Device is compared the voltage effective value of the three-phase alternating-current supply with high voltage crossing trigger voltage value；Work as three-phase alternating-current supply
Voltage effective value be lower than high voltage crossing trigger voltage value when, exchange end voltage comparator output end without control signal it is defeated
Out, the tip side for switching relay keeps normally off, so as in the rectification circuit of pitch-controlled system power supply module driving power
Two terminal shortcircuit of thermistor, pitch-controlled system power supply module driving power keep work normally, for pitch motor drive module supply
Electricity；And when there is high voltage fail, causing the voltage effective value of the three-phase alternating-current supply to reach is more than that high voltage crossing touches
When sending out voltage value, the output end of exchange end voltage comparator then exports control signal, and the tip side of control switching relay disconnects,
So that the thermistor in the rectification circuit of pitch-controlled system power supply module driving power is connected in series to DC bus, due to bus current
Flow through thermistor, thermistor temp rises rapidly, and resistance value increases rapidly, pitch-controlled system power supply module driving power export to
The voltage at DC bus end reduces, and triggering backup power supply manages circuit start backup power supply and powers to DC bus end, thus will
Ac high-voltage is isolated with DC bus, while also pitch motor drive module being kept to be able to powered operation.
It can be seen that in above-mentioned control process, when the voltage effective value of three-phase alternating-current supply is lower than high voltage crossing
In the state of trigger voltage value, the thermistor in the rectification circuit of pitch-controlled system power supply module driving power is in short-circuit shape
State, i.e., the thermistor is on the work operating condition of rectification circuit without influence, and pitch-controlled system power supply module driving power rectifies at this time
The work operating condition of circuit completely be consistent in the prior art；And lead to the three-phase alternating-current supply when there is high voltage fail
Voltage effective value reached be more than high voltage crossing trigger voltage value when, then can trigger exchange end voltage comparator control switching
The tip side of relay disconnects, so that the thermistor in the rectification circuit of pitch-controlled system power supply module driving power is connected in series to directly
Bus is flowed, and since the electric current for flowing through thermistor is larger, the thermal sensitive effect of thermistor is obvious, therefore thermistor resistance value liter
It is high, so that voltage of the load on thermistor gradually rises, defeated so as to cause pitch-controlled system power supply module driving power
The voltage to DC bus end gradually decreases out, and triggering backup power supply manages circuit start backup power supply and supplies to DC bus end
Electricity keeps pitch motor drive module to be able to powered operation, to realize the height electricity of pitch-controlled system power supply module driving power
It presses to wear more control to require, so that the pitch motor drive module of Wind turbines has high voltage fail ride-through capability.
It can see by the utility model paddle change system of wind turbines high voltage crossing controller and above-mentioned control process,
It is simple only by thermistor, exchange end voltage collector, exchange end voltage comparator, switching relay etc. is additionally arranged
Circuit element, and combine by driving power, backup power supply and the stand-by power source management original low-voltage variation of circuit in pitch-controlled system
Function is achieved that the control of the high voltage crossing of pitch motor drive module, and technical thought is ingenious, system reform cost and skill
Art difficulty is low, and the high voltage crossing control for pitch motor drive module in Wind turbines provides new technical thought.
When particular technique is implemented, in the utility model paddle change system of wind turbines high voltage crossing controller, occurring
When high voltage fail, the thermistor accessed in rectification circuit can be increased due to thermal sensitive effect resistance value, carry most voltage,
Therefore the selection needs of thermistor are selected according to the demand that voltage carries；And preferably, when selecting thermistor,
It should be able to guarantee that thermistor is at least able to bear the DC voltage more than or equal to 170V in rectification circuit, 170V is equivalent to
The difference of the 560V reference dc voltage on 730V voltage and DC bus after 1.3 times of Alternating Current Power Supply rectifications is more advantageous in this way
In the high voltage crossing standard requirements that realization operates normally under 1.3 times of voltage ratings, while the thermistor selected being required to exist
High voltage can increase rapidly resistance value isolation AC network and DC bus when arriving.End voltage collector is exchanged to become for acquiring
The voltage effective value of the externally input three-phase alternating-current supply of oar system power supply module driving power, can acquire three-phase alternating current
The exchange end voltage collector product of voltage effective value has been mature technology product, can pass through commercially available acquisition.Exchange end electricity
Pressure comparator can be realized using comparator circuit, only, when realizing using comparator circuit, need to design one in circuit
A voltage signal circuit for reaching high voltage crossing trigger voltage value is linked into the reference signal input of comparator circuit, high electricity
More trigger voltage value is pressed to wear to be designed as defeated outside pitch-controlled system power supply module driving power generally according to the needs of high voltage crossing
1.1 times to 1.3 times of the three-phase alternating-current supply reference voltage virtual value entered, can make circuit modification to a certain extent in this way
Cost and system power dissipation have a degree of increase；As another technical implementation way, exchanging end voltage comparator can also be with
Voltage value is carried out relatively to be achieved by programming Control using digital signal processor, can be incited somebody to action in this way by Programming
The reference voltage value that digital signal processor carries out voltage comparison is set as high voltage crossing trigger voltage value (such as pitch-controlled system
1.1 times to 1.3 times of the externally input three-phase alternating-current supply reference voltage virtual value of power supply module driving power), it avoids
The cost and circuit power consumption for increasing design high voltage crossing trigger voltage signal circuit are programmed using digital signal processor and are realized
Voltage value comparing function is also electronic technology highly developed in the prior art, and technology realization is more simple, is more favorable to letter
Change system reform work.Switching relay then uses the common closed type switching relay of paddle change system of wind turbines in the prior art
Device product.
Finally, it is stated that above embodiments are merely intended for describing the technical solutions of the present application, but not for limiting the present application, although ginseng
The utility model is described in detail according to embodiment, those skilled in the art should understand that, it can be practical to this
Novel technical solution is modified or replaced equivalently, without departing from the objective and range of technical solutions of the utility model,
It should all cover in the scope of the claims of the utility model.
Claims (3)
1. a kind of paddle change system of wind turbines high voltage crossing controller, for the pitch motor drive module for Wind turbines
Execute high voltage crossing control, including pitch-controlled system power supply module driving power, the pitch-controlled system power supply module driving power
Circuit is managed including rectification circuit, filter-capacitor circuit, backup power supply and backup power supply, is provided in the rectification circuit
Charging resistor；It is characterized in that, positioned at charging resistor in the rectification circuit of the pitch-controlled system power supply module driving power
Front end has also been arranged in series thermistor；It further include exchange end voltage collector, exchange end voltage comparator and switching relay；
The exchange end voltage collector is for acquiring the externally input three-phase alternating-current supply of pitch-controlled system power supply module driving power
Voltage effective value, and the output end for exchanging end voltage collector is electrically connected to the comparison signal input of exchange end voltage comparator
End；The reference voltage value of the exchange end voltage comparator is high voltage crossing trigger voltage value, and exchange end voltage compares
The output end of device is electrically connected with the control terminal of switching relay；The switching relay is closed type relay, and switches relay
The tip side of device is connected in parallel on the both ends of thermistor in the rectification circuit.
2. paddle change system of wind turbines high voltage crossing controller according to claim 1, which is characterized in that the rectified current
Thermistor is able to bear the DC voltage more than or equal to 170V in road, and resistance value isolation is capable of increasing when high voltage arrives
AC network and DC bus.
3. paddle change system of wind turbines high voltage crossing controller according to claim 1, which is characterized in that the high voltage
Passing through trigger voltage value is the externally input three-phase alternating-current supply reference voltage virtual value of pitch-controlled system power supply module driving power
1.1 times to 1.3 times.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201822237623.7U CN209072089U (en) | 2018-12-28 | 2018-12-28 | A kind of paddle change system of wind turbines high voltage crossing controller |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201822237623.7U CN209072089U (en) | 2018-12-28 | 2018-12-28 | A kind of paddle change system of wind turbines high voltage crossing controller |
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| Publication Number | Publication Date |
|---|---|
| CN209072089U true CN209072089U (en) | 2019-07-05 |
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ID=67102415
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201822237623.7U Active CN209072089U (en) | 2018-12-28 | 2018-12-28 | A kind of paddle change system of wind turbines high voltage crossing controller |
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| CN (1) | CN209072089U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109474018A (en) * | 2018-12-28 | 2019-03-15 | 重庆科凯前卫风电设备有限责任公司 | A kind of paddle change system of wind turbines high voltage crossing control system and method |
| CN110635672A (en) * | 2019-09-27 | 2019-12-31 | 杭州电子科技大学 | Frequency converter high voltage ride through method based on direct current side voltage division |
-
2018
- 2018-12-28 CN CN201822237623.7U patent/CN209072089U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109474018A (en) * | 2018-12-28 | 2019-03-15 | 重庆科凯前卫风电设备有限责任公司 | A kind of paddle change system of wind turbines high voltage crossing control system and method |
| CN110635672A (en) * | 2019-09-27 | 2019-12-31 | 杭州电子科技大学 | Frequency converter high voltage ride through method based on direct current side voltage division |
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