CN109578206B - Control device of autonomous side deflection fan - Google Patents
Control device of autonomous side deflection fan Download PDFInfo
- Publication number
- CN109578206B CN109578206B CN201811645499.6A CN201811645499A CN109578206B CN 109578206 B CN109578206 B CN 109578206B CN 201811645499 A CN201811645499 A CN 201811645499A CN 109578206 B CN109578206 B CN 109578206B
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- fan
- circuit
- voltage
- microprocessor
- control
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- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims abstract description 22
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 22
- 239000010703 silicon Substances 0.000 claims abstract description 22
- 238000002955 isolation Methods 0.000 claims description 27
- 238000005070 sampling Methods 0.000 claims description 15
- 238000007493 shaping process Methods 0.000 claims description 5
- 238000005516 engineering process Methods 0.000 abstract description 3
- 230000008034 disappearance Effects 0.000 abstract description 2
- 239000003990 capacitor Substances 0.000 description 2
- 238000011217 control strategy Methods 0.000 description 2
- 238000001514 detection method Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000004146 energy storage Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03D—WIND MOTORS
- F03D7/00—Controlling wind motors
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03D—WIND MOTORS
- F03D17/00—Monitoring or testing of wind motors, e.g. diagnostics
-
- 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
- Y02E10/72—Wind turbines with rotation axis in wind direction
Abstract
The invention relates to a control device of an autonomous side air deflection machine. The invention uses the silicon controlled rectifier technology, changes the traditional diode rectification into diode plus silicon controlled rectifier rectification, and utilizes the characteristic of higher withstand voltage of the silicon controlled rectifier (up to 1600V). When the system detects that the current wind speed exceeds the set wind speed, the control circuit cuts off the controllable silicon for rectification, and at the moment, the voltage in the direct current circuit is controlled within the safety range of components and parts, and the controllable silicon tolerates the high voltage generated by the generator. At the moment, due to the disappearance of the load torque, the autonomous cornering protection of the generator can accelerate, the cornering function of the tail beam assembly of the fan is realized, the wind power absorbed by the wind wheel is reduced, and the rotating speed of the fan is reduced, so that the fan enters a safe operation interval.
Description
Technical Field
The invention relates to an electric control device of a middle-small-sized autonomous lateral deflection fan.
Background
When the wind speed reaches the design yaw protection rotating speed, the wind wheel moment of the fan is larger than the yaw moment, the tail beam component of the fan performs the yaw action, the power absorbed by the fan is reduced, and the rotating speed of the fan is reduced, so that the automatic yaw protection function of the fan is realized.
When the fan realizes the side deflection function, the balance among wind wheel torque, generator torque and load torque is required to be considered; the balance between the wind wheel moment and the side deflection moment has a certain contradiction. In the traditional control strategy, due to the existence of load torque, a part of wind wheel torque can be counteracted, and when the rotating speed of the fan reaches the designed cornering rotating speed, the wind wheel torque cannot be larger than the cornering torque, and the cornering protection cannot be realized. Once the load torque is withdrawn, the generator enters an idle state, the rotating speed of the generator rises, and the direct-current voltage rises, so that components of the control system are damaged.
In the current control technology of small and medium-sized fans, direct current voltage is obtained by directly rectifying fan input through a rectifier bridge, then a subsequent electrolytic capacitor is connected for energy storage, and the subsequent stage is used for converting the direct current voltage into direct current load through a DC/DC module or converting the DC/AC module into alternating current voltage for alternating current load. The withstand voltage of the electrolytic capacitor in the circuit is 450VDC, and the highest voltage of the power device is 600-650 VDC.
The circuit cannot realize the separation between alternating current and direct current. In order to ensure the safety of components in the system, the direct-current voltage must be controlled to be less than 450VDC, and a control strategy requires the utilization of a load torque control mode, so that the safety of the circuit can be ensured without disengaging a load in the circuit.
Disclosure of Invention
The purpose of the invention is that: therefore, when the fan is automatically laterally deflected, the lateral deflection protection reliably acts. Furthermore, the function of protecting the wind driven generator and the control system is realized.
In order to achieve the above purpose, the technical scheme of the invention is to provide a control device of an autonomous side bias fan, which comprises a three-phase rectifying circuit, wherein three-phase alternating voltage output by the fan is converted into direct current bus voltage through the three-phase rectifying circuit, and diodes D1, D2 and D3 are arranged at the lower tube of the three-phase rectifying circuit; the first control signal end of the microprocessor generates first three-way control signals through the first three photoelectric isolation chips, the first three-way control signals are respectively connected with the control ends of the controllable silicon Q1, Q3 and Q5, when the first control signal end gives a 12V voltage signal, the first photoelectric isolation chip is turned on, and when the first control signal end gives a 0V voltage signal, the first photoelectric isolation chip is turned off; the control signal end of the microprocessor respectively generates three paths of control signals II through three photoelectric isolation chips II, the three paths of control signals II are respectively connected with the control ends of the controllable silicon Q2, Q4 and Q6, when the control signal end II gives a 12V voltage signal, the photoelectric isolation chip II is cut off, and when the control signal end II gives a 0V voltage signal, the photoelectric isolation chip II is conducted;
the wind speed measuring device is characterized by further comprising an anemometer for measuring wind speed, the anemometer is connected with an acquisition signal input end of the microprocessor, when the microprocessor detects that the current wind speed exceeds the preset wind speed through the anemometer, a first control signal end of the microprocessor gives a 0V voltage signal, and a first photoelectric isolation chip is cut off, so that the thyristors Q1, Q3 and Q5 are cut off, and the three-phase rectifying circuit is cut off.
Preferably, the microprocessor further comprises an isolation circuit, and the direct current bus voltage supplies power to the microprocessor after passing through the isolation circuit.
Preferably, the direct current bus voltage detection circuit further comprises a differential sampling circuit, wherein the input end of the differential sampling circuit is connected with the direct current bus voltage, and the differential sampling circuit outputs a direct current voltage signal Vdc with reduced equal ratio to the microprocessor.
Preferably, after the microprocessor obtains the dc voltage signal Vdc, if the dc voltage signal Vdc exceeds a set value, the second control signal end gives a 0V voltage signal, the first control signal end gives a 12V voltage signal, and the three-phase rectifying circuit is short-circuited, so as to realize a braking function of the fan.
Preferably, the three-phase rectification circuit further comprises a Hall current device, wherein the Hall current device collects a current signal I_in output by the three-phase rectification circuit and sends the current signal I_in to the microprocessor.
Preferably, the fan speed measuring circuit further comprises a fan speed measuring circuit, the fan speed measuring circuit comprises a sampling resistor for sampling and shaping the U phase and the V phase of the three-phase alternating voltage output by the fan, a shaping circuit connected with the sampling resistor, and an isolating circuit connected with the shaping circuit, and square wave signals FINUV and FINUW generated by the two isolating circuits are sent to the microprocessor.
The invention uses the silicon controlled rectifier technology, changes the traditional diode rectification into diode plus silicon controlled rectifier rectification, and utilizes the characteristic of higher withstand voltage of the silicon controlled rectifier (up to 1600V). When the system detects that the current wind speed exceeds the set wind speed, the control circuit cuts off the controllable silicon for rectification, and at the moment, the voltage in the direct current circuit is controlled within the safety range of components and parts, and the controllable silicon tolerates the high voltage generated by the generator. At the moment, due to the disappearance of the load torque, the autonomous cornering protection of the generator can accelerate, the cornering function of the tail beam assembly of the fan is realized, the wind power absorbed by the wind wheel is reduced, and the rotating speed of the fan is reduced, so that the fan enters a safe operation interval.
Drawings
FIG. 1 is a schematic diagram of the overall circuit of the present invention;
FIG. 2 is a power supply circuit of the present invention;
FIG. 3 is a fan speed measurement circuit;
FIG. 4 is a current sampling circuit;
fig. 5 is a voltage sampling circuit.
Detailed Description
The invention will be further illustrated with reference to specific examples. It is to be understood that these examples are illustrative of the present invention and are not intended to limit the scope of the present invention. Further, it is understood that various changes and modifications may be made by those skilled in the art after reading the teachings of the present invention, and such equivalents are intended to fall within the scope of the claims appended hereto.
As shown in fig. 1, the control device of the autonomous side bias fan comprises a three-phase rectifying circuit, wherein three-phase alternating voltage U, V, W output by the fan is converted into direct-current BUS voltage dc_bus+ and dc_bus-through the three-phase rectifying circuit, diodes D1, D2 and D3 are arranged at the lower tube of the three-phase rectifying circuit, thyristors Q1, Q3 and Q5 are arranged at the upper tube of the three-phase rectifying circuit, and thyristors Q2, Q4 and Q6 are respectively connected in anti-parallel with two ends of the thyristors Q1, Q3 and Q5; a WORK at a control signal end of the microprocessor generates three paths of control signals KA1, KA2 and KA3 through three photoelectric isolation chips U4, U5 and U6 respectively, and the three paths of control signals KA1, KA2 and KA3 are connected with control ends of controllable silicon Q1, Q3 and Q5 respectively. When the control signal end WORK gives a 12V voltage signal, the photoelectric isolation chips U4, U5 and U6 are conducted, and when the zero crossing of the voltages applied to the two ends of the thyristors Q1, Q3 and Q5 is positive, the voltage is negative, the switching is stopped, so that the zero crossing conduction design function is realized. When the control signal end WORK gives a 0V voltage signal, the photoelectric isolation chips U4, U5 and U6 are cut off, the thyristors Q1, Q3 and Q5 are cut off, and the three-phase rectifying circuit is disconnected. The control signal end two SHORT of the microprocessor generates three paths of control signals two KB1, KB2 and KB3 through three photoelectric isolation chips two U1, U2 and U3 respectively, and the three paths of control signals two KB1, KB2 and KB3 are respectively connected with the control ends of controllable silicon Q2, Q4 and Q6. When the control signal terminal II SHORT gives a 12V voltage signal, the photoelectric isolation chips II U1, U2 and U3 are cut off, and the controllable silicon Q2, Q4 and Q6 are cut off. When the control signal terminal II SHORT gives a 0V voltage signal, the photoelectric isolation chips II U1, U2 and U3 are conducted, and the controllable silicon Q2, Q4 and Q6 are conducted. In order to protect the safety of the silicon controlled rectifier, an overvoltage control circuit is designed in the circuit, when the rotating speed of the fan reaches the rotating speed of overvoltage protection action, the lower tube of the three-phase rectifying circuit is controlled to conduct bidirectionally, the output short circuit of the fan is realized, and the speed reduction of the fan is realized by utilizing electromagnetic torque. When the rotating speed of the fan does not meet the requirement of the lateral deviation action, the microprocessor controls the thyristors Q1, Q3 and Q5 to be conducted, the three-phase full-wave rectification function of fan input is achieved, and power is supplied to a rear-stage DC/DC or DC/AC circuit. When the rotating speed of the fan reaches the requirement of the lateral deviation action, the microprocessor controls the thyristors Q1, Q3 and Q5 to be disconnected, and the connection between the fan output and the direct current circuit is cut off. The fan is accelerated to enter a lateral deviation protection state.
The invention also comprises an anemometer for measuring wind speed, wherein the anemometer is connected with the acquisition signal input end of the microprocessor, when the microprocessor detects that the current wind speed exceeds the preset wind speed through the anemometer, the control signal end of the microprocessor gives out a 0V voltage signal, and the photoelectric isolation chips U4, U5 and U6 are cut off, so that the thyristors Q1, Q3 and Q5 are cut off, and the three-phase rectifying circuit is cut off.
The circuit is provided with a special auxiliary power supply circuit, and auxiliary power supply is generated by utilizing electric energy generated by rotation of the fan, and the auxiliary power supply is independent of an external power supply. Specifically, as shown in fig. 2, the three-phase alternating voltage U, V, W output by the fan and the rectified dc_bus+ signal are isolated by a diode, and then +12v voltage is generated by a circuit as shown in the figure, so that the power supply circuit is used. As long as the fan is rotating, there can be a continuous power supply.
The invention can detect signals such as fan rotating speed, direct current bus voltage, direct current bus current and the like. As shown in FIG. 3, the fan rotation speed measuring circuit measures the frequencies of the U and W phases, the signals are sampled through resistors, shaped, isolated to obtain square wave signals FINUV and FINUW, and the square wave signals FINUV and FINUW are sent to the microprocessor for reading and processing.
As shown in fig. 4, the hall current device U7 obtains an dc current signal i_in with an equal ratio reduced, and sends the signal to the microprocessor for reading.
As shown in fig. 5, the DC BUS voltages dc_bus+, dc_bus-are subjected to differential sampling to obtain an DC voltage signal Vdc with reduced equal ratio, and the DC voltage signal Vdc is sent to a microprocessor for reading processing. After the microprocessor obtains the direct-current voltage signal Vdc, if the direct-current voltage signal Vdc exceeds a set value, the control signal end two SHORT gives a 0V voltage signal, the control signal end one WORK gives a 12V voltage signal, and the three-phase rectifying circuit is SHORT-circuited, so that the braking function of the fan is realized.
Claims (6)
1. The control device of the autonomous side deflection fan comprises a three-phase rectifying circuit, wherein three-phase alternating current voltage U, V, W output by the fan is converted into direct current BUS voltage DC_BUS+ and DC_BUS-, and diodes D1, D2 and D3 are arranged at the lower tube of the three-phase rectifying circuit, and the control device is characterized in that upper tubes of the three-phase rectifying circuit are controlled silicon Q1, Q3 and Q5, and controlled silicon Q2, Q4 and Q6 are respectively connected in anti-parallel with two ends of the controlled silicon Q1, Q3 and Q5; the control signal end one WORK of the microprocessor generates three paths of control signals one KA1, KA2 and KA3 through three photoelectric isolation chips one U4, U5 and U6 respectively, the three paths of control signals one KA1, KA2 and KA3 are respectively connected with the control ends of the controllable silicon Q1, Q3 and Q5, when the control signal end one WORK gives a 12V voltage signal, the photoelectric isolation chips one U4, U5 and U6 are conducted, and when the control signal end one WORK gives a 0V voltage signal, the photoelectric isolation chips one U4, U5 and U6 are cut off; the control signal end two SHORT of the microprocessor generates three paths of control signals two KB1, KB2 and KB3 through three photoelectric isolation chips two U1, U2 and U3 respectively, the three paths of control signals two KB1, KB2 and KB3 are respectively connected with the control ends of controllable silicon Q2, Q4 and Q6, when the control signal end two SHORT gives out a 12V voltage signal, the photoelectric isolation chips two U1, U2 and U3 are cut off, and when the control signal end two SHORT gives out a 0V voltage signal, the photoelectric isolation chips two U1, U2 and U3 are conducted;
the wind speed measuring device is characterized by further comprising an anemometer for measuring wind speed, the anemometer is connected with an acquisition signal input end of the microprocessor, when the microprocessor detects that the current wind speed exceeds the preset wind speed through the anemometer, a first WORK at a control signal end of the microprocessor gives out a 0V voltage signal, and a first U4, a first U5 and a second U6 of the photoelectric isolation chip are cut off, so that the thyristors Q1, Q3 and Q5 are cut off, and the three-phase rectifying circuit is cut off.
2. The control device for an autonomous side bias fan according to claim 1, further comprising an isolation circuit, wherein the DC BUS voltage dc_bus+, dc_bus-is provided to power the microprocessor via the isolation circuit.
3. The control device of an autonomous side bias fan according to claim 1, further comprising a differential sampling circuit, wherein an input of the differential sampling circuit is connected to the DC BUS voltage dc_bus+, dc_bus-, and the differential sampling circuit outputs an isostatically reduced DC voltage signal Vdc to the microprocessor.
4. The control device of an autonomous side fan as claimed in claim 3, wherein after the microprocessor obtains the dc voltage signal Vdc, if the dc voltage signal Vdc exceeds a set value, the control signal terminal two SHORT gives a 0V voltage signal, the control signal terminal one WORK gives a 12V voltage signal, and the three-phase rectifying circuit is SHORT-circuited to implement a braking function of the fan.
5. The control device of an autonomous side bias fan according to claim 1, further comprising a hall current device, wherein the hall current device U7 collects a current signal i_in output from the three-phase rectifying circuit and sends the current signal i_in to the microprocessor.
6. The control device of an autonomous side bias fan according to claim 1, further comprising a fan speed measuring circuit, wherein the fan speed measuring circuit comprises a sampling resistor for sampling a U phase and a V phase of the three-phase ac voltage U, V, W output by the fan, a shaping circuit connected with the sampling resistor, and an isolation circuit connected with the shaping circuit, and square wave signals FINUV and FINUW generated by the two isolation circuits are sent to the microprocessor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811645499.6A CN109578206B (en) | 2018-12-30 | 2018-12-30 | Control device of autonomous side deflection fan |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811645499.6A CN109578206B (en) | 2018-12-30 | 2018-12-30 | Control device of autonomous side deflection fan |
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| Publication Number | Publication Date |
|---|---|
| CN109578206A CN109578206A (en) | 2019-04-05 |
| CN109578206B true CN109578206B (en) | 2024-01-30 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201811645499.6A Active CN109578206B (en) | 2018-12-30 | 2018-12-30 | Control device of autonomous side deflection fan |
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Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN111082719A (en) * | 2019-12-26 | 2020-04-28 | 上海致远绿色能源股份有限公司 | Combined damping power changing control device |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2006084294A1 (en) * | 2005-02-10 | 2006-08-17 | Fronius International Gmbh | Rectifier system for supply in a 3-phase network and rectifier unit for a 3-phase network |
| CN103016378A (en) * | 2012-11-30 | 2013-04-03 | 杭州顿力电器有限公司 | Driving circuit and driving method of external rotor electronic control type fan adjuster |
| CN103414205A (en) * | 2013-07-12 | 2013-11-27 | 国家电网公司 | Wind farm super capacitor energy storage type unified power quality conditioner |
| CN209743088U (en) * | 2018-12-30 | 2019-12-06 | 上海致远绿色能源股份有限公司 | Control device of autonomous side-bias fan |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7045966B2 (en) * | 2004-07-07 | 2006-05-16 | Osram Sylvania Inc. | Resonant inverter including feed back circuit having phase compensator and controller |
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2018
- 2018-12-30 CN CN201811645499.6A patent/CN109578206B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2006084294A1 (en) * | 2005-02-10 | 2006-08-17 | Fronius International Gmbh | Rectifier system for supply in a 3-phase network and rectifier unit for a 3-phase network |
| CN103016378A (en) * | 2012-11-30 | 2013-04-03 | 杭州顿力电器有限公司 | Driving circuit and driving method of external rotor electronic control type fan adjuster |
| CN103414205A (en) * | 2013-07-12 | 2013-11-27 | 国家电网公司 | Wind farm super capacitor energy storage type unified power quality conditioner |
| CN209743088U (en) * | 2018-12-30 | 2019-12-06 | 上海致远绿色能源股份有限公司 | Control device of autonomous side-bias fan |
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| CN109578206A (en) | 2019-04-05 |
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