WO2021254031A1 - 风力发电机及其功率转换电路的控制方法和装置 - Google Patents

风力发电机及其功率转换电路的控制方法和装置 Download PDF

Info

Publication number
WO2021254031A1
WO2021254031A1 PCT/CN2021/093161 CN2021093161W WO2021254031A1 WO 2021254031 A1 WO2021254031 A1 WO 2021254031A1 CN 2021093161 W CN2021093161 W CN 2021093161W WO 2021254031 A1 WO2021254031 A1 WO 2021254031A1
Authority
WO
WIPO (PCT)
Prior art keywords
bus
power switch
generator
armature
power
Prior art date
Application number
PCT/CN2021/093161
Other languages
English (en)
French (fr)
Inventor
张鲁华
陈晓静
刘嘉明
葛昊祥
方杭杭
Original Assignee
上海电气风电集团股份有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 上海电气风电集团股份有限公司 filed Critical 上海电气风电集团股份有限公司
Publication of WO2021254031A1 publication Critical patent/WO2021254031A1/zh

Links

Images

Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P9/00—Arrangements for controlling electric generators for the purpose of obtaining a desired output
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J3/00—Circuit arrangements for ac mains or ac distribution networks
    • H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
    • H02J3/381—Dispersed generators
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P9/00—Arrangements for controlling electric generators for the purpose of obtaining a desired output
    • H02P9/006—Means for protecting the generator by using control
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J2300/00—Systems for supplying or distributing electric power characterised by decentralized, dispersed, or local generation
    • H02J2300/20—The dispersed energy generation being of renewable origin
    • H02J2300/28—The renewable source being wind energy
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P2101/00—Special adaptation of control arrangements for generators
    • H02P2101/15—Special adaptation of control arrangements for generators for wind-driven turbines

Definitions

  • This application relates to the field of wind power generation, and in particular to a method and device for controlling a wind generator and its power conversion circuit.
  • the wind turbine In the actual application process, the wind turbine is in the grid-connected state, when the voltage of the grid suddenly drops, or the high-voltage recovery and other working conditions, the hardware of the wind turbine is damaged or disconnected, and the operation of the wind turbine is affected. Have an adverse effect.
  • This application provides an improved control method and device for a wind power generator and its power conversion circuit.
  • An embodiment of the application provides a method for controlling a power conversion circuit of a wind power generator.
  • the wind power generator includes a motor connected to the power conversion circuit, and the power conversion circuit includes a generator-side converter connected to the motor.
  • the DC bus connected to the generator-side converter, wherein the control method includes: obtaining the DC bus voltage of the DC bus; if the DC bus voltage is higher than a first preset value, controlling the The power switch of the part of the generator-side converter is turned on, so that the armature resistance of the motor is connected with the DC bus to discharge the electric energy of the DC bus; if the voltage of the DC bus is lower than the second preset Value, the power switch of the part of the generator-side converter is controlled to be turned off, so as to disconnect the armature resistance of the motor and the DC bus to end the discharge; the second preset value is lower than The first preset value.
  • the motor includes the three-phase armature resistors connected in a star shape; if the DC bus voltage is higher than the first preset value, the power of the part of the generator-side converter is controlled Switching on includes: controlling the power switch connecting the first end of the DC bus and the armature resistance of one of the phases, and connecting the second end of the DC bus to at least one of the other two phases. The power switch of the armature resistance is turned on.
  • control the power switch connecting the first end of the DC bus and the armature resistance of one of the phases, and the second end of the DC bus and the armature of at least one of the other two phases includes: if the DC bus voltage is higher than the first preset value, controlling the power switch connecting the first end of the DC bus and one of the phases of the armature resistor, and connecting The second end of the DC bus bar is turned on with the power switch of the armature resistor of the other phase, so that the two-phase armature resistors are connected in series with the DC bus bar, and the electric energy of the DC bus bar is discharged.
  • control the power switch connecting the first end of the DC bus and the armature resistance of one of the phases, and the second end of the DC bus and the armature of at least one of the other two phases includes: if the DC bus voltage is higher than the first preset value, controlling the power switch connecting the first end of the DC bus and one of the phases of the armature resistor, and connecting The power switches of the second end of the DC bus and the other two phases of the armature resistors are turned on, so that the other two phases of the armature resistors connected to the second end of the DC bus are connected in parallel with the DC bus.
  • One of the armature resistors of the first end of the phase is connected in series with the DC bus, and discharges the electric energy of the DC bus.
  • the first terminal of the DC bus is a positive terminal
  • the second terminal of the DC bus is a negative terminal
  • a power switch connecting the first terminal of the DC bus and a part of the armature resistance is controlled, and The power switch connecting the second end of the DC bus and the armature resistance of at least one other phase is turned on, including: if the DC bus voltage is higher than the first preset value, controlling the power switch connected to the DC bus
  • the power switch connecting the positive terminal and the armature resistance of one phase, and the power switch connecting the negative terminal of the DC bus and the other two phases of the armature resistance are turned on, so that the other power switches connected to the negative terminal of the DC bus
  • the two-phase armature resistors are connected in series with the armature resistor of one of the phases connected to the positive end of the DC bus, and are connected with the DC bus to discharge the electric energy of the DC bus.
  • the first terminal of the DC bus is a negative terminal
  • the second terminal of the DC bus is a positive terminal
  • a power switch connecting the first terminal of the DC bus and a part of the armature resistance is controlled, and The power switch connecting the second end of the DC bus and the armature resistance of at least one other phase is turned on, including: if the DC bus voltage is higher than the first preset value, controlling the power switch connected to the DC bus
  • the power switch of the negative terminal and the armature resistance of one phase, and the power switch connecting the positive terminal of the DC bus and the other two phases of the armature resistance are turned on, so that the other power switches connected to the positive terminal of the DC bus
  • the two-phase armature resistors are connected in series with one of the armature resistors connected to the negative end of the DC bus, and connected with the DC bus to discharge the electric energy of the DC bus.
  • the wind power generator further includes a braking unit connected between the positive terminal and the negative terminal of the DC bus, and the braking unit includes a braking resistor and a braking unit connected in series with the braking resistor.
  • the control method includes: if the DC bus voltage is higher than the first preset value, controlling the brake switch to be turned on, so that the braking resistor is connected to the DC bus, and the DC bus is discharged The electric energy of the bus; if the DC bus voltage is lower than the second preset value, the brake switch is controlled to be turned off to disconnect the braking resistor and the DC bus to end the discharge; the second The preset value is lower than the first preset value.
  • An embodiment of the present application provides a computer-readable storage medium on which a computer program is stored, where the program is executed by a processor to implement the method for controlling a power conversion circuit of a wind turbine as described in any one of the above.
  • An embodiment of the present application provides a control device for a power conversion circuit of a wind power generator, which includes one or more processors for implementing the control method of the power conversion circuit of a wind power generator as described in any one of the above.
  • the embodiment of the application provides a wind power generator, which includes: a motor; a power conversion circuit connected to the motor and used for converting the electric energy output by the motor; the power conversion circuit includes a generator-side converter, a direct current A bus and a grid-side converter, the generator-side converter is electrically connected to the motor, the DC bus is electrically connected to the generator-side converter, and the grid-side converter is electrically connected to the DC bus; and In the above-mentioned control device of the power conversion circuit of the wind power generator, the control device is electrically connected to the generator-side converter.
  • the power switch of the part that controls the machine-side converter is turned on, so that the armature resistance of the motor is connected to the DC bus as a bleeder resistance, and the electric energy of the DC bus is discharged in the DC bus.
  • the DC bus voltage is controlled within the voltage tolerance range to ensure the normal grid-connected operation of the motor, thereby protecting the motor, the DC bus and the wind generator from damage.
  • Figure 1 is a schematic diagram of a related art wind power generator
  • FIG. 2 is a schematic diagram of another related art wind power generator
  • Fig. 3 is a schematic diagram of the structure of the wind power generator of the application.
  • Fig. 4 is a schematic circuit diagram of the wind generator shown in Fig. 3;
  • Fig. 5 is a schematic diagram of a partial circuit of an embodiment of the wind generator shown in Fig. 4;
  • Fig. 6 is a flow chart of the control method of the power conversion circuit of the wind generator shown in Fig. 5;
  • Fig. 7 is a flowchart of an embodiment of step S2 of the method for controlling the power conversion circuit of the wind turbine shown in Fig. 6;
  • Fig. 8 is a flowchart of an embodiment of step S20 of the method for controlling the power conversion circuit of the wind turbine shown in Fig. 7;
  • Figure 9 is a waveform diagram of the discharge voltage of the DC bus and the discharge current of the armature resistance
  • Fig. 10 is a flowchart of another embodiment of step S20 of the method for controlling the power conversion circuit of the wind turbine shown in Fig. 7;
  • FIG. 11 is a flowchart of an embodiment of step S201 of the method for controlling the power conversion circuit of the wind turbine shown in FIG. 10;
  • FIG. 12 is a flowchart of another embodiment of step S201 of the method for controlling the power conversion circuit of the wind turbine shown in FIG. 10;
  • Fig. 13 is a schematic partial circuit diagram of another embodiment of the wind power generator shown in Fig. 4;
  • Fig. 14 is a flowchart of a control method of the power conversion circuit of the wind generator shown in Fig. 13;
  • Figure 15 is a waveform diagram of the discharge voltage of the DC bus, the discharge current of the armature resistance, and the discharge current of the braking resistor;
  • Fig. 16 is a schematic diagram of an embodiment of a control device for a power conversion circuit of a wind generator according to the present application
  • Fig. 17 is a schematic diagram of an embodiment of the wind power generator of this application.
  • Fig. 1 is a schematic diagram of a wind power generator 100 in the related art.
  • the wind generator 100 includes a motor 101, a generator-side converter 102, a DC bus 103, and a grid-side converter 104.
  • the wind generator 100 is electrically connected to the grid 105, and the generator-side converter 102 is electrically connected.
  • the motor 101, the grid-side converter 104 are electrically connected to the grid 105, and the DC bus 103 is connected between the generator-side converter 102 and the grid-side converter 104.
  • the generator-side converter 102 and the grid-side converter 104 are coupled through a DC bus 103.
  • Fig. 2 is a schematic diagram of another related art wind power generator 200.
  • the related technology shown in FIG. 2 is similar to the related technology shown in FIG. 1. In the related technology shown in FIG. Between them, they are connected in parallel with the DC bus 206.
  • the bleeder device 201 includes a bleeder resistor 202 and a bleeder switch 203 connected to the bleeder resistor 202.
  • the electric energy of the DC bus 206 is discharged by adding a discharge device 201.
  • the bleeder switch 203 When the DC bus voltage of the DC bus 206 rises to or exceeds the first preset value of the DC bus 206, the bleeder switch 203 is controlled to turn on, so that the bleeder resistor 202 is connected to the DC bus to discharge the DC bus.
  • the sharply increased power when the DC bus voltage of the DC bus drops to or below the second preset value of the DC bus, the bleed switch 203 is controlled to be turned off, so that the bleed resistance 202 is cut out, thereby reducing the voltage of the DC bus.
  • the DC bus voltage is controlled within the voltage tolerance range.
  • a high-power bleeder resistor 202 needs to be configured.
  • two bleeder resistors 202 with a volume of 500mm*450mm*100mm need to be used.
  • the bleeder resistor 202 results in a larger size of the bleeder 201, which occupies more space in the cabinet.
  • the bleeder resistor 202 discharges, it will also generate a lot of heat, and there is a certain fire hazard.
  • a special heat sink is required. For example, it is necessary to install a cooling fan or add a corresponding cooling water circuit, which also increases the cost of the wind turbine.
  • the embodiments of the present application provide an improved method and device for controlling a wind generator and its power conversion circuit.
  • FIG. 3 is a schematic diagram of the structure of the wind power generator 300 of this application.
  • the wind generator 300 includes a tower 302 extending from a supporting surface 301, a nacelle 303 installed on the tower 302, and a rotor 304 assembled to the nacelle 303.
  • the rotor 304 includes a rotatable hub 3040 and at least one rotor blade 3041, and the rotor blade 3041 is connected to the hub 3040 and extends outward from the hub 3040.
  • the rotor 304 includes three rotor blades 3041.
  • the rotor 304 may include more or fewer rotor blades.
  • a plurality of rotor blades 3041 may be spaced around the hub 3040 to facilitate rotation of the rotor 304 so that wind energy can be converted into usable mechanical energy, and then into electrical energy.
  • a motor (not shown) is provided in the nacelle 303, and the motor (not shown) can be connected to the rotor 304 for generating electrical power from the mechanical energy generated by the rotor 304.
  • a control device (not shown) is also provided in the nacelle 20, and the control device (not shown) is communicably connected to the electrical components of the wind turbine 300 to control the operation of such components.
  • the control device may also be provided in any other component of the wind generator 300 or at a location outside the wind generator 300.
  • the control device (not shown) may include a computer or other processing unit.
  • control device may include appropriate computer-readable instructions, and the computer-readable instructions configure the control device (not shown) when executed to perform various functions, for example, Receive, transmit and/or execute the control signal of the wind power generator 300.
  • control device may be configured to control various operation modes of the wind generator 300 (for example, a start or stop sequence) and/or control various components of the wind generator 300.
  • FIG. 4 is a schematic circuit diagram of the wind power generator 300 shown in FIG. 3.
  • the wind power generator 300 includes a motor 305 and a power conversion circuit 306 connected to the motor 305.
  • the motor 305 may include an asynchronous motor or a synchronous motor.
  • the motor 305 is a three-phase motor, and includes three-phase windings 311, 312, and 313.
  • the three-phase windings 311, 312, and 313 are connected in a star shape, with a difference of 120 ° in electrical angle in space.
  • the three-phase windings 311, 312, and 313 are connected in delta.
  • the motor 305 may be a multi-phase motor, such as a six-phase motor.
  • the power conversion circuit 306 can receive the electrical signal output by the motor 305, and convert the electrical signal to output.
  • the power conversion circuit 306 can convert the alternating current signal into a direct current signal, and then into a power frequency alternating current output.
  • the power conversion circuit 306 is connected to the three-phase windings 311, 312, and 313, and is used to receive the electrical signals output by the three-phase windings 311, 312, and 313, and convert the electrical signals to output.
  • the wind power generator 300 includes a control device 307 connected to the power conversion circuit 306 for controlling the power conversion circuit 306 to convert the electrical signal output by the motor 305.
  • the wind power generator 300 includes a transformer 308 connected to the power conversion circuit 306, and the transformer 308 is electrically connected to the power grid 309.
  • the converted electrical signal output by the power conversion circuit 306 can be boosted by the transformer 308 and then transmitted to the power grid 309.
  • the transformer 308 may include a three-winding transformer, and the three-winding transformer is connected to the power conversion circuit 306.
  • the voltage rating of the three-winding transformer is 66kV/690V/690V
  • the grid rating of the power grid 309 is 66kV.
  • the power conversion circuit 306 includes a generator-side converter 314, a grid-side converter 315, and a DC bus 316 connected between the generator-side converter 314 and the grid-side converter 315.
  • the generator-side converter 314 is connected to the motor 305
  • the grid-side converter 315 is connected to the transformer 308, and the generator-side converter 314 is connected to the grid-side converter 315.
  • the generator-side converter 314 includes a rectifier
  • the grid-side converter 315 includes an inverter.
  • the electrical signal output by the motor 305 is an alternating current signal
  • the machine-side converter 314 is used to convert the electrical signal output by the motor 305 into a direct current signal
  • the grid-side converter 315 is used to convert the direct current signal into a converted output electrical signal
  • the converted output electrical signal is output to the transformer 308.
  • the converted output electric signal is an alternating current signal with a frequency different from that of the electric signal.
  • the electrical signal is a low-frequency alternating current signal
  • the converted output electrical signal is a power frequency alternating current signal that meets the requirements of the power grid.
  • the control device 307 may include a machine-side control device 317 and a grid-side control device 318.
  • the machine-side control device 317 is connected to the machine-side converter 314 for controlling the machine-side converter 314 to convert the electrical signal output by the motor 305 into a direct current signal.
  • the grid-side control device 318 is connected to the grid-side converter 315 for controlling the grid-side converter 315 to convert the direct current signal into a converted output electrical signal.
  • the machine-side control device 317 can control the voltage and/or power of the converted DC electrical signal
  • the grid-side control device 318 can control the voltage and/or power of the converted output electrical signal.
  • the machine-side control device 317 and the network-side control device 318 may include any suitable programmable circuits or devices, such as digital signal processors (Digital Signal Processor, DSP), Field Programmable Gate Array (Field Programmable Gate Array, FPGA), Programmable Logic Controller (PLC) and Application Specific Integrated Circuit (ASIC), etc.
  • DSP Digital Signal Processor
  • FPGA Field Programmable Gate Array
  • PLC Programmable Logic Controller
  • ASIC Application Specific Integrated Circuit
  • FIG. 5 is a schematic partial circuit diagram of an embodiment of the wind power generator 300 shown in FIG. 4.
  • the motor 305 includes a three-phase armature resistor connected in a star shape, and the three-phase armature resistor includes a first armature resistor 320, a second armature resistor 321, and a third armature resistor 322.
  • the first armature resistor 320, the second armature resistor 321, and the third armature resistor 322 may be connected in other ways, such as delta connection.
  • the resistance value of the three-phase armature resistance may be the DC resistance value of the three-phase winding of the motor 305 itself.
  • the DC resistance value can be said to be the DC resistance of the three-phase winding wire, and the DC parameter of the three-phase winding, which can be measured with a multimeter.
  • the generator-side converter 314 includes a first power switch 323, a second power switch 324, a third power switch 325, a fourth power switch 326, a fifth power switch 327, and a sixth power switch.
  • Switch 328, the first armature resistor 320 is connected to the positive terminal 3160 of the DC bus 316 through the first power switch 323, and is connected to the negative terminal 3161 of the DC bus 316 through the second power switch 324, and the second armature resistor 321 is connected to the negative terminal 3161 of the DC bus 316 through the first power switch 323.
  • the three-power switch 325 is connected to the positive terminal 3160 of the DC bus 316, and is connected to the negative terminal 3161 of the DC bus 316 through the fourth power switch 326, and the third armature resistor 322 is connected to the positive terminal of the DC bus 316 through the fifth power switch 327.
  • the terminal 3160 is connected to the negative terminal 3161 of the DC bus 316 through the sixth power switch 328.
  • the first power switch 323, the second power switch 324, the third power switch 325, the fourth power switch 326, the fifth power switch 327, and the sixth power switch 328 are all IGBTs (Insulated Gate Bipolar Transistor, Insulated gate bipolar transistor) switch, IGBT switch can be turned on and off in a very short time, with high sensitivity and fast switching speed.
  • IGBT switch Insulated Gate Bipolar Transistor, Insulated gate bipolar transistor
  • the first power switch 323, the second power switch 324, the third power switch 325, the fourth power switch 326, the fifth power switch 327, and the sixth power switch 328 may also adopt other power switches. It is not limited in this application.
  • the collector of the first power switch 323 is connected to the positive terminal 3160 of the DC bus 316, and the emitter of the first power switch 323 is connected to the first armature resistor 320.
  • the collector of the second power switch 324 is connected to the first armature resistor 320, and the emitter of the second power switch 324 is connected to the negative terminal 3161 of the DC bus 316.
  • the collector of the third power switch 325 is connected to the positive terminal 3160 of the DC bus 316, and the emitter of the third power switch 325 is connected to the second armature resistor 321.
  • the collector of the fourth power switch 326 is connected to the second armature resistor 321, and the emitter of the fourth power switch 326 is connected to the negative terminal 3161 of the DC bus 316.
  • the collector of the fifth power switch 327 is connected to the positive terminal 3160 of the DC bus 316, and the emitter of the fifth power switch 327 is connected to the third armature resistor 322.
  • the collector of the sixth power switch 328 is connected to the third armature resistor 322, and the emitter of the sixth power switch 328 is connected to the negative terminal 3161 of the DC bus 316.
  • the gates of the first power switch 323, the second power switch 324, the third power switch 325, the fourth power switch 326, the fifth power switch 327, and the sixth power switch 328 are used as the control terminals of the switches. It can be connected to different control ports of the machine-side control device 317, and the different control ports independently control the power switch. In some embodiments, different control ports can synchronously control corresponding power switches.
  • the working principle and connection mode of the machine-side control device 317 provided by the power conversion circuit 306 can refer to the working mode and connection mode of the machine-side control device 317 shown in FIG. 4, which will not be repeated here.
  • the control method of the power conversion circuit 306 of the wind generator 300 needs to be adjusted to make the wind generator 300 In the grid-connected state, the active power transmitted by the generator-side converter 314 to the DC bus 316 side and the active power output by the grid-side converter 315 to the grid 309 are balanced.
  • FIG. 6 is a flowchart of a control method of the power conversion circuit 306 of the wind power generator 300 shown in FIG. 5. As shown in Fig. 6, the control method of the power conversion circuit 401 of the wind power generator 300 includes steps S1-S3.
  • step S1 the DC bus voltage of the DC bus is obtained.
  • the DC bus voltage detection circuit of the DC bus 316 is provided inside the machine-side control device 317, and the DC bus voltage of the DC bus 316 can be obtained.
  • the machine-side control device 317 may be a processor, and the DC bus voltage detection circuit may be integrated in the processor, which simplifies the circuit structure and saves costs.
  • the DC bus voltage detection circuit can detect the DC bus voltage of the DC bus 316 in the form of a combination of software and hardware.
  • step S2 if the DC bus voltage is higher than the first preset value, the part of the power switch that controls the machine-side converter 314 is turned on, so that the armature resistance of the motor 305 is connected to the DC bus 316, and the DC bus is discharged 316 electric energy.
  • the DC bus voltage of the DC bus 316 normally works around 1100V.
  • the first preset value may be 1180V. In some other embodiments, the first preset value can also be set to other values.
  • the generator-side control device 317 controls the generator-side converter 314 to stop modulation, and then controls the part of the power switch of the generator-side converter 314 to turn on. In order to make the armature resistance of the motor 305 communicate with the DC bus 316, the electric energy of the DC bus 316 is discharged. In some embodiments, the generator-side control device 317 controls part of the power switch of the generator-side converter 314 to turn on, and at the same time controls other power switches to turn off, so that the electric energy of the DC bus 316 is stably discharged.
  • the modulation means that the generator-side converter 314 adopts SVPWM (Space Vector Pulse Width Modulation) or SPWM (Sinusoidal Pulse Width Modulation, sinusoidal pulse width modulation) modulation methods by controlling the power switch according to The logic set by the program is turned on or off.
  • the bleeder means that the power switch of the conducting part establishes a bleeder path between the DC bus 316 and the motor resistance.
  • the grid-side control device 318 can still control the grid-side converter 315 to maintain the modulation state. First, it can ensure that the motor 305 does not run off the grid, and then the DC bus 316 The power transmission provides a power transmission channel to transmit the power of the DC bus 316 to the grid-side converter 315.
  • step S3 if the DC bus voltage is lower than the second preset value, the part of the power switch that controls the machine-side converter 314 is turned off to disconnect the armature resistance of the motor 305 and the DC bus 316, and the discharge ends.
  • the second preset value is lower than the first preset value.
  • the DC bus voltage of the DC bus 316 normally works around 1100V.
  • the second preset value may be 1120V. In some other embodiments, the second preset value can also be set to other values.
  • the machine-side control device 317 controls the power switch of the machine-side converter 314 to turn off to disconnect the armature resistance of the motor 305 from the DC bus 316 , The discharge ends, and then the control engine-side converter 314 starts to modulate.
  • the DC bus voltage between the first preset value and the second preset value may be the bleeder voltage connected between the armature resistance of the motor 305 and the DC bus 316, and when the DC bus voltage changes from the first preset value During the process of reducing the set value to the second preset value, the wind generator 300 can be connected to the grid without interruption and support the restoration of the power grid 309 until the power grid 309 returns to normal.
  • the DC bus voltage of the DC bus 316 is controlled within the voltage tolerance range, the normal grid-connected operation of the motor 305 is ensured, thereby protecting the motor 305, the DC bus 316 and the wind generator 300 from damage.
  • there is no need to add a bleeder device which can save space in the wind generator 300 and does not need to add a heat dissipation device, thereby reducing the cost of the wind generator 300.
  • the working voltage at which the DC bus voltage of the DC bus 316 normally works is not limited in this application.
  • the safe voltage range value of the DC bus voltage of the DC bus 316 and the upper limit value or the lower limit value of the safe voltage range value can be set to other values, which are not limited in this application.
  • FIG. 7 is a flowchart of an embodiment of step S2 of the method for controlling the power conversion circuit 306 of the wind turbine 300 shown in FIG. 6. As shown in FIG. 7, step S2 of the method for controlling the power conversion circuit 306 of the wind turbine 300 includes step S20. in,
  • Step S20 Control the power switch connecting the first end of the DC bus 316 with one phase armature resistance, and the power switch connecting the second end of the DC bus 316 with at least one phase armature resistance of the other two phases to be turned on.
  • the first end of the DC bus 316 is in communication with the armature resistance of one of the phases through the corresponding conductive power switch, and the second end of the DC bus 316 is in communication with the armature resistance of at least one of the other two phases through the corresponding conductive power switch. Therefore, the electric energy of the DC bus 316 is transmitted to the armature resistance through the turned-on power switch, and is discharged.
  • the first end of the DC bus 316 may be the positive end 3160.
  • the second end of the DC bus 316 may be the negative end 3161.
  • the motor 305 when the DC bus voltage of the DC bus 316 is higher than the first preset value, and the machine-side control device 317 controls the machine-side converter 314 to stop modulation, the motor 305 will not generate useful work.
  • the active power transmitted by the side converter 102 to the DC bus 103 is converted into the kinetic energy of the rotor of the motor 305, and the three-phase armature resistance of the motor 305 can be used as a bleeder resistor to bleed the electric energy accumulated on the DC bus 316 ,
  • the speed of the motor 305 will be accelerated, but the function of the motor 305 itself will not be affected.
  • the control of the power switch has nothing to do with the resistance of the armature resistance.
  • the resistance of the armature resistance affects the discharge speed of the DC bus voltage of the DC bus 316, thereby affecting the DC bus voltage of the DC bus 316. Bleeding time.
  • the smaller the resistance of the bleeder resistor composed of multiple armature resistors the greater the bleeder current, the greater the active power generated, the faster the bleeder speed, and the shorter the bleed time .
  • FIG. 8 is a flowchart of an embodiment of step S20 of the method for controlling the power conversion circuit 306 of the wind turbine 300 shown in FIG. 7. As shown in FIG. 8, step S20 of the method for controlling the power conversion circuit 306 of the wind power generator 300 includes step S200. in,
  • Step S200 if the DC bus voltage is higher than the first preset value, control the power switch connecting the first end of the DC bus 316 and one of the phase armature resistances, and the second end of the DC bus 316 and the other phase armature
  • the power switch of the resistor is turned on, so that the two-phase armature resistors are connected in series with the DC bus 316, and the electric energy of the DC bus 316 is discharged.
  • the other power switches of the controller-side converter 314 are turned off.
  • the DC bus voltage of the DC bus 316 normally works around 1100V.
  • the first preset value may be 1180V, and the second preset value may be 1120V. In some other embodiments, the first preset value and the second preset value may also be set to other values.
  • the first terminal of the DC bus 316 may be the positive terminal 3160, and the second terminal of the DC bus 316 may be the negative terminal 3161. Combining the embodiments shown in FIG. 5 and FIG. 8, the first end of the DC bus 316 is the positive terminal 3160, and the second end of the DC bus 316 is the negative terminal 3161.
  • the generator-side control device 317 controls the generator-side converter 314 to stop modulation, and can control the first power switch 323 and the fourth power switch 326 to conduct.
  • the first armature resistor 320 and the second armature resistor 321 are connected in series with the DC bus 316 to discharge the electric energy of the DC bus 316.
  • the second power switch 324, the third power switch 325, the fifth power switch 327, and the sixth power switch 328 are controlled to be turned off.
  • the machine-side control device 317 controls the first power switch 323 and the fourth power switch 326 of the machine-side converter 314 to turn off, so as to turn off the first power switch.
  • the armature resistance 320, the second armature resistance 321, and the DC bus 316 terminate the discharge.
  • the generator-side control device 317 controls the generator-side converter 314 to stop modulation, and can control the third power switch 325 and the second power switch 324 to conduct , So that the second armature resistor 321 and the first armature resistor 320 are connected in series with the DC bus 316 to discharge the electric energy of the DC bus 316.
  • the first power switch 323, the fourth power switch 326, the fifth power switch 327, and the sixth power switch 328 are controlled to be turned off.
  • the generator-side control device 317 controls the second power switch 324 and the third power switch 325 of the generator-side converter 314 to turn off, so as to turn off the first
  • the armature resistance 320, the second armature resistance 321, and the DC bus 316 terminate the discharge.
  • the generator-side control device 317 controls the generator-side converter 314 to stop modulation, and can control the first power switch 323 and the sixth power switch 328 to conduct , So that the first armature resistor 320 and the third armature resistor 322 are connected in series with the DC bus 316 to discharge the electric energy of the DC bus 316.
  • the second power switch 324, the third power switch 325, the fourth power switch 326, and the fifth power switch 327 are controlled to be turned off.
  • the generator-side control device 317 controls the first power switch 323 and the sixth power switch 328 of the generator-side converter 314 to turn off, so as to turn off the first power switch.
  • the armature resistance 320, the third armature resistance 322 and the DC bus 316 terminate the discharge.
  • the generator-side control device 317 controls the generator-side converter 314 to stop modulation, and can control the fifth power switch 327 and the second power switch 324 to conduct , So that the third armature resistor 322 and the first armature resistor 320 are connected in series with the DC bus 316 to discharge the electric energy of the DC bus 316.
  • the first power switch 323, the third power switch 325, the fourth power switch 326, and the sixth power switch 328 are controlled to be turned off.
  • the generator-side control device 317 controls the second power switch 324 and the fifth power switch 327 of the generator-side converter 314 to turn off to turn off the first
  • the armature resistance 320, the third armature resistance 322 and the DC bus 316 terminate the discharge.
  • the generator-side control device 317 controls the generator-side converter 314 to stop modulation, and can control the third power switch 325 and the sixth power switch 328 to conduct , So that the second armature resistor 321 and the third armature resistor 322 are connected in series with the DC bus 316 to discharge the electric energy of the DC bus 316.
  • the first power switch 323, the second power switch 324, the fourth power switch 326, and the fifth power switch 327 are controlled to be turned off.
  • the generator-side control device 317 controls the third power switch 325 and the sixth power switch 328 of the generator-side converter 314 to turn off, so as to turn off the second
  • the armature resistance 321, the third armature resistance 322 and the DC bus 316 terminate the discharge.
  • the generator-side control device 317 controls the generator-side converter 314 to stop modulation, and can control the fifth power switch 327 and the fourth power switch 326 to be turned on , So that the third armature resistor 322 and the second armature resistor 321 are connected in series with the DC bus 316 to discharge the electric energy of the DC bus 316.
  • the first power switch 323, the second power switch 324, the third power switch 325, and the sixth power switch 328 are controlled to be turned off.
  • the generator-side control device 317 controls the fourth power switch 326 and the fifth power switch 327 of the generator-side converter 314 to turn off to turn off the second
  • the armature resistance 321, the third armature resistance 322 and the DC bus 316 terminate the discharge.
  • the resistance value of the first armature resistor 320, the second armature resistor 321, and the third armature resistor 322 is R
  • the two resistors connected to the DC bus 316 are
  • the resistance value of the bleeder circuit composed of armature resistors in series is 2R
  • the armature resistance of the motor 305 is used as a bleeder resistor to connect with the DC bus 316 to discharge the electric energy of the DC bus 316 to control the DC bus voltage of the DC bus 316
  • the normal grid-connected operation of the motor 305 is ensured, thereby protecting the motor 305, the DC bus 316 and the wind generator 300 from damage.
  • there is no need to add a bleeder device which can save space in the wind generator 300 and does not need to add a heat dissipation device, thereby reducing the cost of the wind generator 300.
  • FIG. 9 is a waveform diagram of the discharge voltage of the DC bus 316 and the discharge current of the armature resistance.
  • the active power of the turbine-side converter 314 is 3000kW, and when the active power transmitted by the turbine-side converter 314 is greater than
  • the active power transmitted by the grid-side converter 315 causes the DC bus voltage to rise to the first preset value of 1180V, any of the above-mentioned embodiments shown in FIG.
  • the armature resistance of the motor 305 is used as a bleeder
  • the resistor is connected to the DC bus 316, and the DC bus voltage is pulled down to the second preset value of 1120V to discharge the electric energy of the DC bus 316.
  • the DC bus voltage of the DC bus 316 can be controlled within the voltage tolerance range and the motor 305 can be guaranteed
  • the normal grid-connected operation of the inverter protects the motor 305 and the wind generator 300 from damage.
  • the waveform 700 is the waveform diagram of the discharge voltage of the DC bus 316, the abscissa is time, the ordinate is the voltage, and the waveform 701 is the waveform diagram of the bleeder current of the armature resistance, the abscissa is time, and the ordinate is Is the current, as shown in Figure 9, the peak value of the bleeder current of the bleeder resistor is about 2500A.
  • the peak value of the bleeder current of the bleeder resistor is measured by an oscilloscope.
  • FIG. 10 is a flowchart of another embodiment of step S20 of the method for controlling the power conversion circuit 306 of the wind turbine 300 shown in FIG. 7. As shown in FIG. 10, step S20 of the method for controlling the power conversion circuit 306 of the wind power generator 300 includes step S201. in,
  • Step S201 If the DC bus voltage is higher than the first preset value, control the power switch connecting the first end of the DC bus 316 and one of the armature resistances, and the second end of the DC bus 316 and the other two-phase armatures.
  • the power switch of the resistor is turned on, so that the other two-phase armature resistors connected to the second end of the DC bus 316 are connected in series with one of the phase armature resistors connected to the first end of the DC bus 316, and are connected to the DC bus 316 to leak Discharge the electric energy of the DC bus 316.
  • the other power switches of the controller-side converter 314 are turned off.
  • the DC bus voltage of the DC bus 316 normally works around 1100V.
  • the first preset value may be 1180V, and the second preset value may be 1120V.
  • the first preset value and the second preset value may also be set to other values, and the second preset value is lower than the first preset value.
  • the first end of the DC bus 316 may be the positive terminal 3160, and the second end of the DC bus 316 may be the negative terminal 3161. In other embodiments, the first end of the DC bus 316 may be the negative terminal 3161, and the second end of the DC bus 316 may be the positive terminal 3160.
  • FIG. 11 is a flowchart of an embodiment of step S201 of the method for controlling the power conversion circuit 306 of the wind turbine 300 shown in FIG. 10. As shown in FIG. 11, step S201 of the method for controlling the power conversion circuit 306 of the wind turbine 300 includes step S2010.
  • Step S2010 if the DC bus voltage is higher than the first preset value, control the power switch connecting the positive terminal 3160 of the DC bus 316 and one of the armature resistances, and the negative terminal 3161 of the DC bus 316 and the other two-phase armatures.
  • the power switch of the resistor is turned on, so that the other two-phase armature resistors connected to the negative end 3161 of the DC bus 316 are connected in series with one of the phase armature resistors connected to the positive end 3160 of the DC bus 316, and communicate with the DC bus 316, The electric energy of the DC bus 316 is discharged.
  • the other power switches of the controller-side converter 314 are turned off.
  • the first end of the DC bus 316 is the positive terminal 3160, and the second end of the DC bus 316 is the negative terminal 3161.
  • the generator-side control device 317 controls the generator-side converter 314 to stop modulation, and can control the first power switch 323, the fourth power switch 326, and the sixth power switch.
  • the power switch 328 is turned on, so that the second armature resistor 321 is connected in parallel with the third armature resistor 322 and then connected in series with the first armature resistor 320, connected with the DC bus 316, and discharges the electric energy of the DC bus 316.
  • the second power switch 324, the third power switch 325, and the fifth power switch 327 are controlled to be turned off.
  • the machine-side control device 317 controls the first power switch 323, the fourth power switch 326, and the sixth power switch 328 of the machine-side converter 314 to turn off , To disconnect the first armature resistor 320, the second armature resistor 321, the third armature resistor 322 and the DC bus 316 to end the discharge.
  • the generator-side control device 317 controls the generator-side converter 314 to stop modulation, and can control the third power switch 325, the second power switch 324, and the second power switch 324.
  • the six-power switch 328 is turned on, so that the first armature resistor 320 is connected in parallel with the third armature resistor 322 and then connected in series with the second armature resistor 321, connected to the DC bus 316, and discharges the electric energy of the DC bus 316.
  • the first power switch 323, the fourth power switch 326, and the fifth power switch 327 are controlled to be turned off.
  • the generator-side control device 317 controls the second power switch 324, the third power switch 325, and the sixth power switch 328 of the generator-side converter 314 to turn off , To disconnect the first armature resistor 320, the second armature resistor 321, the third armature resistor 322 and the DC bus 316 to end the discharge.
  • the generator-side control device 317 controls the generator-side converter 314 to stop modulation, and can control the fifth power switch 327, the second power switch 324, and the second power switch 324.
  • the four-power switch 326 is turned on, so that the first armature resistor 320 is connected in parallel with the second armature resistor 321 and then connected in series with the third armature resistor 322, connected with the DC bus 316, and discharges the electric energy of the DC bus 316.
  • the first power switch 323, the third power switch 325, and the sixth power switch 328 are controlled to be turned off.
  • the generator-side control device 317 controls the second power switch 324, the fourth power switch 326, and the fifth power switch 327 of the generator-side converter 314 to turn off , To disconnect the first armature resistor 320, the second armature resistor 321, the third armature resistor 322 and the DC bus 316 to end the discharge.
  • the resistance value of the first armature resistance 320, the second armature resistance 321, and the third armature resistance 322 is R, so the armature resistance connected to the DC bus 316 is The resistance value is 1.5R.
  • the embodiment shown in Fig. 8 has a fast discharge speed and a short discharge time.
  • the embodiment shown in FIG. 11 has a smaller resistance value of the armature resistance connected to the DC bus 316. In any of the embodiments shown in FIG.
  • the two-phase armature resistance of the motor 305 is used in parallel and then connected in series with the other one-phase armature resistance as a bleeder resistor to communicate with the DC bus 316 to discharge the electric energy of the DC bus 316,
  • the DC bus voltage of the DC bus 316 can be controlled within the voltage tolerance range, and the normal grid-connected operation of the motor 305 can be ensured, thereby protecting the motor 305, the DC bus 316 and the wind generator 300 from damage.
  • there is no need to add a braking device which can save space in the wind power generator 300, and does not need to add a heat dissipation device, thereby reducing the cost of the wind power generator 300.
  • Fig. 12 is a flowchart of another embodiment of step S201 of the method for controlling the power conversion circuit of the wind turbine shown in Fig. 10. As shown in FIG. 12, step S201 of the method for controlling the power conversion circuit 306 of the wind power generator 300 includes step S2011.
  • Step S2011 if the DC bus voltage is higher than the first preset value, control the power switch connecting the negative terminal 3161 of the DC bus 316 and one of the armature resistances, and the positive terminal 3160 of the DC bus 316 and the other two-phase armatures.
  • the power switch of the resistor is turned on, so that the other two-phase armature resistors connected to the positive end 3160 of the DC bus 316 are connected in series with one of the phase armature resistors connected to the negative end 3161 of the DC bus 316, and communicate with the DC bus 316, The electric energy of the DC bus 316 is discharged.
  • the other power switches of the controller-side converter 314 are turned off.
  • the first terminal of the DC bus 316 is the negative terminal 3161, and the second terminal of the DC bus 316 is the positive terminal 3160.
  • the generator-side control device 317 controls the generator-side converter 314 to stop modulation, and can control the first power switch 323, the third power switch 325, and the sixth power switch 323.
  • the power switch 328 is turned on, so that the first armature resistor 320 is connected in parallel with the second armature resistor 321 and then connected in series with the third armature resistor 322, connected with the DC bus 316, and discharges the electric energy of the DC bus 316.
  • the second power switch 324, the fourth power switch 326, and the fifth power switch 327 are controlled to be turned off.
  • the generator-side control device 317 controls the first power switch 323, the third power switch 325, and the sixth power switch 328 of the generator-side converter 314 to turn off , To disconnect the first armature resistor 320, the second armature resistor 321, the third armature resistor 322 and the DC bus 316 to end the discharge.
  • the generator-side control device 317 controls the generator-side converter 314 to stop modulation, and can control the first power switch 323, the fifth power switch 327, and the first power switch 327.
  • the four-power switch 326 is turned on, so that the first armature resistor 320 is connected in parallel with the third armature resistor 322 and then connected in series with the second armature resistor 321, connected with the DC bus 316, and discharges the electric energy of the DC bus 316.
  • the second power switch 324, the third power switch 325, and the sixth power switch 328 are controlled to be turned off.
  • the generator-side control device 317 controls the first power switch 323, the fourth power switch 326 and the fifth power switch 327 of the generator-side converter 314 to turn off , To disconnect the first armature resistor 320, the second armature resistor 321, the third armature resistor 322 and the DC bus 316 to end the discharge.
  • the generator-side control device 317 controls the generator-side converter 314 to stop modulation, and can control the third power switch 325, the fifth power switch 327, and the third power switch 327.
  • a power switch 4013 is turned on, the second armature resistor 321 is connected in parallel with the third armature resistor 322 and then connected in series with the first armature resistor 320, connected with the DC bus 316, and discharges the electric energy of the DC bus 316.
  • the second power switch 324, the fourth power switch 326, and the sixth power switch 328 are controlled to be turned off.
  • the generator-side control device 317 controls the first power switch 323, the third power switch 325, and the fifth power switch 327 of the generator-side converter 314 to turn off , To disconnect the first armature resistor 320, the second armature resistor 321, the third armature resistor 322 and the DC bus 316 to end the discharge.
  • the resistance value of the first armature resistance 320, the second armature resistance 321, and the third armature resistance 322 is R
  • the armature resistance connected to the DC bus 316 is The resistance value is 1.5R.
  • the embodiment shown in FIG. 8 has a fast discharge speed and a short discharge time.
  • the embodiment shown in FIG. 12 has a smaller resistance value of the armature resistance connected with the DC bus 316.
  • the embodiment shown in FIG. 12 has the same resistance value of the armature resistor connected to the DC bus 316, and the discharge speed and the discharge time are the same.
  • the two-phase armature resistance of the motor 305 is connected in series with the other one-phase armature resistance as a bleeder resistor to connect with the DC bus 316 to discharge the electric energy of the DC bus 316.
  • the DC bus voltage of the DC bus 316 is controlled within the voltage tolerance range to ensure the normal grid-connected operation of the motor 305, thereby protecting the motor 305, the DC bus 316 and the wind generator 300 from damage.
  • there is no need to add a braking device which can save space in the wind turbine 300 and does not need to add a heat dissipation device, thereby reducing the cost of the wind turbine 300.
  • FIG. 13 is a schematic partial circuit diagram of another embodiment of the wind power generator 400 of the present application shown in FIG. 4.
  • the wind generator 400 shown in FIG. 13 is similar to the wind generator 300 shown in FIG. 5.
  • a braking device 401 is added to the wind power generator 400, where the braking device 401 includes a braking resistor 402 and a braking switch 403 connected in series with the braking resistor 402.
  • One end of the braking device 401 is connected to the positive end 4110 of the DC bus 411, and the other end of the braking device 401 is connected to the negative end 4111 of the DC bus 411.
  • the wind power generator 400 includes a motor 404 and a power conversion circuit 405.
  • the motor 404 includes a three-phase armature resistor.
  • the three-phase armature resistor includes a first armature resistor 407, a second armature resistor 408, and a third armature resistor 409.
  • the power conversion circuit 405 includes a generator-side converter 410 and a DC bus 411 connected to the generator-side converter 410.
  • the DC bus 411 includes a positive terminal 4110 and a negative terminal 4111.
  • the braking device 401 is connected to the positive terminal of the DC bus 411. Between terminal 4110 and negative terminal 4111.
  • the generator-side converter 410 includes a first power switch 412, a second power switch 413, a third power switch 414, a fourth power switch 415, a fifth power switch 416, and a sixth power switch 417.
  • the motor 404 and the power conversion circuit 405 shown in FIG. 13 are similar to the motor 305 and the power conversion circuit 306 shown in FIG.
  • the control terminal of the braking device 401 and the control terminal of the power switch are connected to different control ports of the machine-side control device (not shown), so that the power switch and the brake switch 403 can be turned on synchronously.
  • the power conversion circuit 405 further includes a brake controller (not shown), which is electrically connected to the brake switch 403 of the brake device 401 to control the brake switch 403.
  • the brake controller may include any suitable programmable circuit or device, such as a digital signal processor (Digital Signal Processor, DSP), a Field Programmable Gate Array (Field Programmable Gate Array, FPGA), Programmable Logic Controller (PLC), Application Specific Integrated Circuit (ASIC), etc.
  • the brake controller can realize the control of the brake switch 403 in the form of a combination of software and hardware.
  • the brake controller and the machine-side control device 317 can be controlled synchronously.
  • the braking resistor 402 can be a braking resistor with a small resistance, and the braking resistor 402 can be used as an energy consumption unit connected to the DC bus 411.
  • the DC bus voltage of the DC bus 411 is higher than normal Excess energy is consumed at working voltage.
  • the original need to use two bleeder resistors 202 can be reduced to one, which saves the space in the wind turbine 400, and
  • the heat generated is very small, and there is no need to configure a heat dissipation device, thereby reducing the cost of the wind generator 400.
  • an additional energy storage unit is connected to the DC bus 411, and when it is detected that the DC bus voltage of the DC bus 411 is higher than the normal operating voltage, the excess energy is transferred, and the more stored energy is fed into
  • the power grid for example, the energy storage unit may be a battery or the like.
  • the capacity of the grid-side converter (not shown) can also be increased, for example, adding multiple grid-side converters to work in parallel.
  • FIG. 14 is a flowchart of an embodiment of a control method of the power conversion circuit 405 of the wind generator 400 shown in FIG. 13. Compared with the embodiment shown in FIG. 6, the control method of the power conversion circuit 405 of the wind generator 400 shown in FIG. 14 further includes:
  • the brake switch 403 is controlled to be turned off to disconnect the brake resistor 402 and the DC bus 411 to end the discharge, wherein the second preset value is lower than the first preset value.
  • control method includes steps S1, S4, and S5. in,
  • Step S1 Obtain the DC bus voltage of the DC bus 411. Similar to step S1 of the control method shown in FIG. 6, reference may be made to the embodiment shown in FIG. 6, which will not be repeated here.
  • Step S4 If the DC bus voltage is higher than the first preset value, the power switch of the part that controls the machine-side converter 410 is turned on, and the brake switch 403 is controlled to be turned on, so that the armature resistance and the brake resistance of the motor 404 are turned on. 402 is connected to the DC bus 411, and discharges the electric energy of the DC bus 411.
  • the method for controlling part of the power switch of the machine-side converter 410 to be turned on is similar to the corresponding method shown in FIG. 6, and reference may be made to the embodiment shown in FIG. 6 above.
  • the brake switch 403 when the DC bus voltage is higher than the first preset value, can be controlled to be turned on at the same time when the power switch of the part of the control machine-side converter 410 is turned on.
  • the embodiment shown in FIG. 14 adds a bleeder resistor, not only uses the armature resistor, but also uses the brake resistor 402 as a bleeder resistor to communicate with the DC bus 411 to bleed the electric energy of the DC bus 411 to speed up the discharge speed. , Shortening the release time.
  • Step S5 If the DC bus voltage is lower than the second preset value, the power switch of the part of the control machine-side converter 410 is turned off, and the brake switch 403 is controlled to be turned off to disconnect the armature resistance of the motor 404 and the brake resistance 402
  • the bleeder ends with the DC bus 411, where the second preset value is lower than the first preset value.
  • the method for controlling part of the power switch of the generator-side converter 410 to be turned off is also similar to the corresponding method shown in FIG. 6. You can refer to the embodiment shown in FIG. 6 above. No longer.
  • the brake switch 403 when the DC bus voltage is lower than the second preset value, when the part of the power switch that controls the machine-side converter 410 is turned off, the brake switch 403 can be controlled to be turned off at the same time to disconnect the power of the motor 404. Pivot resistance, brake switch 403, and DC bus, end the discharge.
  • 15 is a waveform diagram of the discharge voltage of the DC bus 411, the discharge current of the armature resistance, and the discharge current of the braking resistor 402.
  • the active power of the turbine-side converter 410 is 3300kW, and when the active power transmitted by the turbine-side converter 410 is greater than
  • the active power transmitted by the grid-side converter causes the DC bus voltage to rise to the first preset value of 1180V
  • the electric The pivot resistor and the braking resistor 402 are connected with the DC bus 411 as a bleeder resistor, and the DC bus voltage is pulled down to a second preset value of 1120V to discharge the electric energy of the DC bus 411, which can reduce the DC bus voltage of the DC bus 411.
  • Controlling within the voltage tolerance range can ensure the normal grid-connected operation of the motor 404, thereby protecting the motor 404, the DC bus 414 and the wind generator 400 from damage.
  • reducing the number of braking devices 401 can save space in the wind turbine 400 without adding a heat dissipation device, thereby reducing the cost of the wind turbine 400.
  • the waveform 702 is the waveform diagram of the bleeder voltage of the DC bus 411, the abscissa is time, the ordinate is voltage, and the waveform 703 is the waveform of the bleeder current of the armature resistance, the abscissa is time, and the ordinate is Is the current, and the waveform 704 is the waveform diagram of the bleeder current of the braking resistor 402, the abscissa is time, and the ordinate is current.
  • the peak value of the bleeder voltage of the braking resistor 402 is about 1700A
  • the peak value of the bleeder current of the armature resistor is about 2900A.
  • the conversion of the grid-side converter (not shown) is operating normally and will not be affected in any way.
  • the peak value of the discharge voltage of the braking resistor 402 and the peak value of the discharge current of the armature resistance can be measured by an oscilloscope.
  • an appropriate one of the foregoing implementation manners is selected.
  • the braking resistor 402 of the additional braking device 401 may not need to be added for venting.
  • an additional braking resistor 402 of the braking device 401 needs to be added for venting.
  • the present application also provides an embodiment of the control device of the power conversion circuit 306 of the wind generator 300.
  • FIG. 16 is a schematic diagram of an embodiment of a control device 500 for a power conversion circuit of a wind generator according to the present application.
  • the control device 500 includes one or more processors 501 for implementing the control method of the power conversion circuit of the wind turbine in any one of the foregoing embodiments of the control method of the power conversion circuit of the wind turbine. .
  • the embodiment of the control device 500 of the power conversion circuit of the wind power generator of the present application can be applied to the wind power generator.
  • the embodiments of the control device 500 can be implemented by software, or can be implemented by hardware or a combination of software and hardware. Taking software implementation as an example, as a device in a logical sense, it is formed by reading the corresponding computer program instructions in the non-volatile memory into the memory through the processor 501 of the wind turbine where it is located. From a hardware perspective, as shown in FIG. 16, a hardware structure diagram of a wind turbine where the control device 500 of this application is located, except for the processor 501, memory, network interface, and non-volatile memory shown in FIG. In addition to the memory, the wind turbine in which the device is located in the embodiment generally may include other hardware according to the actual function of the wind turbine, which will not be repeated here.
  • the processor 501 may be a central processing unit (Central Processing Unit, CPU), and may also be other general-purpose processors, digital signal processors (Digital Signal Processors, DSPs), and application specific integrated circuits (Application Specific Integrated Circuits). , ASIC), Field-Programmable Gate Array (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc.
  • the general-purpose processor may be a microprocessor or the processor 501 may also be any conventional processor or the like. I won't repeat it here.
  • control device 500 shown in FIG. 16 can refer to the control device 307 shown in FIG. 4 above, and details are not described herein again.
  • FIG. 17 is a schematic diagram of an embodiment of the wind power generator 600 of this application. As shown in FIG. 17, the wind power generator 600 includes a power conversion circuit 601, a motor 602, and the control device 500 of the power conversion circuit of the wind power generator shown in FIG. 16 described above.
  • the power conversion circuit 601 is connected to the motor 602 to convert the electric energy output by the motor 602.
  • the power conversion circuit 601 includes a machine-side converter 6010, a DC bus 6011, and a grid-side converter 6012.
  • the motor 6010 is electrically connected to the motor 602
  • the DC bus 6011 is electrically connected to the machine-side converter 6010
  • the grid-side converter 6012 is electrically connected to the DC bus 6011.
  • the control device 600 is electrically connected to the generator-side converter 6010.
  • the control device 500 includes one or more processors 501 for implementing the control of the power conversion circuit of the wind turbine in any one of the foregoing embodiments of the control method for the power conversion circuit of the wind turbine. method.
  • the control device 500 may control a part of the power switch of the machine-side converter 6010 to be turned on, so that the armature resistance of the motor 602 is used as a bleeder resistor to communicate with the DC bus 6011 to discharge the electric energy of the DC bus 6011 When the DC bus voltage rises, the DC bus voltage is controlled within the voltage tolerance range to ensure the normal grid-connected operation of the motor 602, thereby protecting the motor 602, the DC bus 6011 and the wind generator 600 from damage.
  • the power conversion circuit 601, the machine-side converter 6010, and the grid-side converter 6012 shown in FIG. 17 may refer to the power conversion circuit 306, the machine-side converter 314, and the grid-side converter shown in FIG. 4 above.
  • the side converter 315 will not be repeated here.
  • the relevant part can refer to the part of the description of the method embodiment.
  • the device embodiments described above are merely illustrative, where the units described as separate components may or may not be physically separate, and the components displayed as units may or may not be physical units, which can be located in One place, or it can be distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this application. Those of ordinary skill in the art can understand and implement it without creative work.
  • the present application also provides a computer-readable storage medium on which a computer program is stored, and when the program is executed by the processor 501, the wind turbine control method of any one of the first aspect is implemented.
  • the computer-readable storage medium may be the internal storage unit of the wind turbine described in any of the foregoing embodiments, such as a hard disk or a memory.
  • the computer-readable storage medium may also be an external storage device of the wind power generator, such as a plug-in hard disk, a smart media card (SMC), an SD card, a flash memory card (Flash Card), etc., equipped on the device.
  • the computer-readable storage medium may also include both an internal storage unit of the wind turbine and an external storage device.
  • the computer-readable storage medium is used to store the computer program and other programs and data required by the wind power generator, and can also be used to temporarily store data that has been output or will be output.

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Control Of Eletrric Generators (AREA)

Abstract

本申请提供一种风力发电机及其功率转换电路的控制方法和装置。控制方法包括：获取直流母线的直流母线电压；若直流母线电压高于第一预设值，控制机侧变流器的部分的功率开关导通，以使电机的电枢电阻与直流母线连通，泄放直流母线的电能；若直流母线电压低于第二预设值，控制机侧变流器的部分的功率开关截止，以断开电机的电枢电阻与直流母线，结束泄放，第二预设值低于第一预设值。在直流母线电压升高时，将直流母线电压控制在电压承受范围内，保证电机的正常并网运行，从而保护电机、直流母线和风力发电机免受损坏。

Description

风力发电机及其功率转换电路的控制方法和装置 技术领域
本申请涉及风力发电领域，尤其涉及一种风力发电机及其功率转换电路的控制方法和装置。
背景技术
随着风力发电技术的发展，风力发电机逐渐发展为现在的双PWM(Pulse width modulation，脉冲宽度调制)背靠背系统的并联运行控制方式。该种方式系统运行稳定，电路可靠性高，在风力发电机中得到了有效的应用。
在实际应用过程中，风力发电机处于并网状态下，当遇到电网的电压突然跌落，或者高电压恢复等工况时，导致风力发电机硬件损坏或脱网，以及对风力发电机的运行产生不良影响。
发明内容
本申请提供一种改进的风力发电机及其功率转换电路的控制方法和装置。
本申请实施例提供一种风力发电机的功率转换电路的控制方法，所述风力发电机包括与所述功率转换电路连接的电机，所述功率转换电路包括与所述电机连接的机侧变流器及与所述机侧变流器连接的直流母线，其中，所述控制方法包括：获取所述直流母线的直流母线电压；若所述直流母线电压高于第一预设值，控制所述机侧变流器的部分的功率开关导通，以使所述电机的电枢电阻与所述直流母线连通，泄放所述直流母线的电能；若所述直流母线电压低于第二预设值，控制所述机侧变流器的部分的所述功率开关截止，以断开所述电机的所述电枢电阻与所述直流母线，结束泄放；所述第二预设值低于所述第一预设值。
可选的，所述电机包括星型连接的三相所述电枢电阻；若所述直流母线电压高于所述第一预设值，控制所述机侧变流器的部分的所述功率开关导通，包括：控制连接所述直流母线的第一端和其中一相所述电枢电阻的功率开关，和连接所述直流母线的第二端和其他两相中的至少一相所述电枢电阻的功率开关导通。
可选的，控制连接所述直流母线的第一端和其中一相所述电枢电阻的功率开关，和连接所述直流母线的第二端和其他两相中的至少一相所述电枢电阻的功率开关导通，包括：若所述直流母线电压高于所述第一预设值，控制连接所述直流母线的第一端和其中一相所述电枢电阻的功率开关，和连接所述直流母线的第二端和其他一相所述电枢电阻的功率开关导通，以使两相所述电枢电阻串联后与所述直流母线连通，泄放所述直流母线的电能。
可选的，控制连接所述直流母线的第一端和其中一相所述电枢电阻的功率开关，和连接所述直流母线的第二端和其他两相中的至少一相所述电枢电阻的功率开关导通，包括：若所述直流母线电压高于所述第一预设值，控制连接所述直流母线的第一端和其中一相所述电枢电阻的功率开关，和连接所述直流母线的第二端和其他两相所述电枢电阻的功率开关导通，以使连接所述直流母线的第二端的其他两相所述电枢电阻并联后与连接所述直流母线的第一端的其中一相所述电枢电阻串联，与所述直流母线连通，泄放所 述直流母线的电能。
可选的，所述直流母线的第一端为正端，所述直流母线的第二端为负端；控制连接所述直流母线的第一端和部分所述电枢电阻的功率开关，和连接所述直流母线的第二端和其他至少一相所述电枢电阻的功率开关导通，包括：若所述直流母线电压高于所述第一预设值，控制连接所述直流母线的正端和其中一相所述电枢电阻的功率开关，和连接所述直流母线的负端和其他两相所述电枢电阻的功率开关导通，以使连接所述直流母线的负端的其他两相所述电枢电阻并联后与连接所述直流母线的正端的其中一相所述电枢电阻串联，与所述直流母线连通，泄放所述直流母线的电能。
可选的，所述直流母线的第一端为负端，所述直流母线的第二端为正端；控制连接所述直流母线的第一端和部分所述电枢电阻的功率开关，和连接所述直流母线的第二端和其他至少一相所述电枢电阻的功率开关导通，包括：若所述直流母线电压高于所述第一预设值，控制连接所述直流母线的负端和其中一相所述电枢电阻的功率开关，和连接所述直流母线的正端和其他两相所述电枢电阻的功率开关导通，以使连接所述直流母线的正端的其他两相所述电枢电阻并联后与连接所述直流母线的负端的其中一相所述电枢电阻串联，与所述直流母线连通，泄放所述直流母线的电能。
可选的，所述风力发电机还包括连接于所述直流母线的正端与负端之间的制动单元，所述制动单元包括制动电阻以及与所述制动电阻串联的制动开关；控制方法包括：若所述直流母线电压高于所述第一预设值，控制所述制动开关导通，以使所述制动电阻与所述直流母线连通，泄放所述直流母线的电能；若所述直流母线电压低于所述第二预设值，控制所述制动开关截止，以断开所述制动电阻与所述直流母线，结束泄放；所述第二预设值低于所述第一预设值。
本申请实施例提供一种计算机可读存储介质，其上存储有计算机程序，其中，该程序被处理器执行时实现如上述任一项所述的风力发电机的功率转换电路的控制方法。
本申请实施例提供一种风力发电机的功率转换电路的控制装置，其中，包括一个或多个处理器，用于实现如上述任一项所述的风力发电机的功率转换电路的控制方法。
本申请实施例提供一种风力发电机，其中，包括：电机；功率转换电路，与所述电机连接，用于转换所述电机输出的电能，所述功率转换电路包括机侧变流器、直流母线和网侧变换器，所述机侧变流器电连接所述电机，所述直流母线与所述机侧变流器电连接，所述网侧变换器与所述直流母线电连接；以及上述风力发电机的功率转换电路的控制装置，所述控制装置电连接所述机侧变流器。
根据本申请实施例提供的技术方案，控制机侧变流器的部分的功率开关导通，以使电机的电枢电阻作为泄放电阻与直流母线连通，泄放直流母线的电能，在直流母线电压升高时，将直流母线电压控制在电压承受范围内，保证电机的正常并网运行，从而保护电机、直流母线和风力发电机免受损坏。
附图说明
图1为相关技术的风力发电机的原理图；
图2为另一相关技术的风力发电机的原理图；
图3为本申请的风力发电机的结构示意图；
图4为图3所示的风力发电机的电路示意图；
图5为图4所示的风力发电机的一个实施例的部分电路示意图；
图6为图5所示的风力发电机的功率转换电路的控制方法的流程图；
图7为图6所示的风力发电机的功率转换电路的控制方法的步骤S2的一个实施例的流程图；
图8为图7所示的风力发电机的功率转换电路的控制方法的步骤S20的一个实施例的流程图；
图9为直流母线的泄放电压与电枢电阻的泄放电流的波形图；
图10为图7所示的风力发电机的功率转换电路的控制方法的步骤S20的另一个实施例的流程图；
图11为图10所示的风力发电机的功率转换电路的控制方法的步骤S201的一个实施例的流程图；
图12为图10所示的风力发电机的功率转换电路的控制方法的步骤S201的另一个实施例的流程图；
图13为图4所示的风力发电机的另一个实施例的部分电路示意图；
图14为图13所示的风力发电机的功率转换电路的控制方法的流程图；
图15为直流母线的泄放电压、电枢电阻的泄放电流及制动电阻的泄放电流的波形图；
图16为本申请的风力发电机的功率转换电路的控制装置的一个实施例的原理图；
图17为本申请的风力发电机的一个实施例的原理图。
具体实施方式
这里将详细地对示例性实施例进行说明，其示例表示在附图中。下面的描述涉及附图时，除非另有表示，不同附图中的相同数字表示相同或相似的要素。以下示例性实施例中所描述的实施方式并不代表与本申请相一致的所有实施方式。相反，它们仅是与如所附权利要求书中所详述的、本申请的一些方面相一致的装置的例子。
在本申请使用的术语是仅仅出于描述特定实施例的目的，而非旨在限制本申请。除非另作定义，本申请使用的技术术语或者科学术语应当为本申请所属领域内具有一般技能的人士所理解的通常意义。本申请说明书以及权利要求书中使用的“一个”或者“一”等类似词语也不表示数量限制，而是表示存在至少一个。“多个”包括两个，相当于至少两个。“包括”或者“包含”等类似词语意指出现在“包括”或者“包含”前面的元件或者物件涵盖出现在“包括”或者“包含”后面列举的元件或者物件及其等同，并不排除其他元件或者物件。“连接”或者“相连”等类似的词语并非限定于物理的或者机械的连接，而且可包括电性的连接，不管是直接的还是间接的。在本申请说明书和所附权利要求书中所使用的单数形式的“一种”、“所述”和“该”也旨在包括多数形式，除非上下文清楚地表示其他含义。还应当理解，本文中使用的术语“和/或”是指并包含一个或多个相关联的列出项目的任何或所有可能组合。
图1为相关技术中的风力发电机100的原理图。如图1所示，风力发电机100包括电机101、机侧变流器102、直流母线103、网侧变流器104，风力发电机100与电网105电连接，机侧变流器102电连接电机101，网侧变流器104电连接电网105，直流母线 103连接于机侧变流器102与网侧变流器104之间。其中，机侧变流器102和网侧变流器104通过直流母线103耦合。
在实际应用过程中，风力发电机100处于并网状态下，当遇到电网105的电压突然跌落，或者高电压恢复等工况时，机侧变流器102传输到直流母线103侧的有功功率大于网侧变流器104输出到电网105的有功功率，将使直流母线103电压升高，导致风力发电机100硬件损坏或脱网，对电机101的运行产生不良影响。
图2为另一相关技术的风力发电机200的原理图。图2所示的相关技术与图1所示的相关技术相似，图2所示的相关技术中风力发电机200增加泄放装置201，连接于机侧变流器204与网侧变流器205之间，与直流母线206并联连接。其中，泄放装置201包括泄放电阻202及与泄放电阻202连接的泄放开关203。针对上述问题，在图2所示的相关技术中，通过增加泄放装置201泄放直流母线206的电能。当直流母线206的直流母线电压升高至或超过直流母线206的第一预设值时，控制泄放开关203开通，以使泄放电阻202接入与直流母线连通，以泄放直流母线上急剧增加的电能，当直流母线的直流母线电压下降至或低于直流母线的第二预设值时，控制泄放开关203关断，以使泄放电阻202切出，由此将直流母线的直流母线电压控制在电压承受范围内。
在实际应用过程中，对于MW级的风力发电机，故障期间直流母线需要泄放的电能达到MJ级。为确保在短时间内使得直流母线的电能能够安全释放，需配置大功率的泄放电阻202。例如，对于2.5MW全功率的风力发电机需要使用两只体积达500mm*450mm*100mm的泄放电阻202。泄放电阻202导致泄放装置201的尺寸较大，占用较多的柜内空间。并且在泄放电阻202泄流时，其自身也会产生较多的热量，存在一定的火灾隐患，为保证泄放电阻202的正常工作及柜内其他器件的安全，需做专门的散热装置，例如，需要加装散热风扇或者增加相应的散热水路，由此也增加了风力发电机成本。
本申请实施例提供一种改进的风力发电机及其功率转换电路的控制方法和装置。
图3为本申请的风力发电机300的结构示意图。如图3所示，风力发电机300包括从支承表面301延伸的塔架302、安装在塔架302上的机舱303，以及组装至机舱303的转子304。转子304包括可旋转的轮毂3040和至少一个转子叶片3041，转子叶片3041连接至轮毂3040且从轮毂3040向外延伸。在图3所示的实施例中，转子304包括三个转子叶片3041。在一些其他实施例中，转子304可包括更多或更少的转子叶片。多个转子叶片3041可围绕轮毂3040隔开，以促进使转子304旋转，以使风能能够换成可用的机械能，且随后转换成电能。
在一些实施例中，机舱303内设置电机(未图示)，电机(未图示)可连接到转子304，以用于从由转子304生成的机械能生成电功率。在一些实施例中，机舱20内还设置控制装置(未图示)，控制装置(未图示)可通信地连接至风力发电机300的电气部件，以便控制此类部件的运行。在一些实施例中，控制装置(未图示)也可设置于风力发电机300的任何其他部件内，或在风力发电机300外的位置。在一些实施例中，控制装置(未图示)可包括计算机或其他处理单元。在一些其他实施例中，控制装置(未图示)可包括合适的计算机可读指令，计算机可读指令在执行时对控制装置(未图示)进 行配置，以便执行各种不同功能，例如，接收、传输和/或执行风力发电机300的控制信号。在一些实施例中，控制装置(未图示)可配置用于控制风力发电机300的各种运行模式(例如，起动或停机序列)和/或控制风力发电机300的各种部件。
图4为图3所示的风力发电机300的电路示意图。如图4所示，风力发电机300包括电机305和与电机305连接的功率转换电路306。电机305可包括异步电机或同步电机。在本实施例中，电机305为三相电机，包括三相绕组311、312和313。三相绕组311、312和313星型连接，在空间上相差120 °的电角度。在一些实施例中，三相绕组311、312和313三角形连接。在其他一些实施例中，电机305可为多相电机，例如六相电机等。
功率转换电路306可接收电机305输出的电信号，并将该电信号进行转换后输出。功率转换电路306可将交流电信号转换为直流电信号，再转换为工频的交流电输出。在本实施例中，功率转换电路306与三相绕组311、312和313连接，用于接收三相绕组311、312和313输出的电信号，并将该电信号进行转换后输出。
在一些实施例中，风力发电机300包括控制装置307，控制装置307和功率转换电路306连接，用于控制功率转换电路306对电机305输出的电信号进行转换。
在一些实施例中，风力发电机300包括与功率转换电路306连接的变压器308，变压器308电连接电网309。功率转换电路306输出的转换后的电信号可由变压器308升压后输送到电网309。变压器308可包括三绕组变压器，三绕组变压器连接于功率转换电路306。在一些实施例中，三绕组变压器的电压等级为66kV/690V/690V，电网309的电网等级为66kV。
在图4所示的实施例中，功率转换电路306包括机侧变流器314和网侧变流器315以及连接于机侧变流器314与网侧变流器315之间的直流母线316。机侧变流器314连接电机305，网侧变流器315连接变压器308，且机侧变流器314连接网侧变流器315。在一些实施例中，机侧变流器314包括整流器，网侧变流器315包括逆变器。电机305输出的电信号为交流电信号，机侧变流器314用于将电机305输出的电信号转换为直流电信号，网侧变流器315用于将直流电信号转换为转换输出电信号，并将转换输出电信号输出给变压器308。此处，转换输出电信号为频率与电信号的频率不同的交流电信号。电信号为低频交流电信号，转换输出电信号为符合电网要求的工频交流电信号。
控制装置307可包括机侧控制装置317和网侧控制装置318，机侧控制装置317连接机侧变流器314，用于控制机侧变流器314将电机305输出的电信号转换为直流电信号。网侧控制装置318连接网侧变流器315，用于控制网侧变流器315将直流电信号转换为转换输出电信号。此处，机侧控制装置317可控制转换得到的直流电信号的电压和/或功率，网侧控制装置318可控制转换得到的转换输出电信号的电压和/或功率。
机侧控制装置317和网侧控制装置318可包括任何合适的可编程电路或者装置，例如数字信号处理器(Digital Signal Processor，DSP)、现场可编程门阵列(Field Programmable Gate Array，FPGA)、可编程逻辑控制器(Programmable Logic Controller，PLC)以及专用集成电路(Application Specific Integrated Circuit，ASIC)等。机侧控制装置317和网侧控制装置318可通过软硬件结合的形式实现控制。
图5为图4所示的风力发电机300的一个实施例的部分电路示意图。在图5所示的实施例中，电机305包括星型连接的三相电枢电阻，三相电枢电阻包括第一电枢电阻320、第二电枢电阻321与第三电枢电阻322。在一些实施例中，第一电枢电阻320、第二电枢电阻321与第三电枢电阻322可为其他连接方式，例如三角形连接。在一些实施例中，三相电枢电阻的阻值可为电机305的三相绕组自身的直流电阻值。直流电阻值可说是三相绕组导线的直流电阻，是三相绕组的直流参数，可用万用表测得。
在图5所示的实施例中，机侧变流器314包括第一功率开关323、第二功率开关324、第三功率开关325、第四功率开关326、第五功率开关327和第六功率开关328，第一电枢电阻320通过第一功率开关323连接至直流母线316的正端3160，且通过第二功率开关324连接至直流母线316的负端3161，第二电枢电阻321通过第三功率开关325连接至直流母线316的正端3160，且通过第四功率开关326连接至直流母线316的负端3161，第三电枢电阻322通过第五功率开关327连接至直流母线316的正端3160，且通过第六功率开关328连接至直流母线316的负端3161。在一些实施例中，第一功率开关323、第二功率开关324、第三功率开关325、第四功率开关326、第五功率开关327、第六功率开关328均为IGBT(Insulated Gate Bipolar Transistor，绝缘栅双极型晶体管)开关，IGBT开关能够在极短时间内完成通断，灵敏度高且开关速度快。在其他一些实施例中，第一功率开关323、第二功率开关324、第三功率开关325、第四功率开关326、第五功率开关327、第六功率开关328也可采用其他功率开关。在本申请中不作限定。
在图5所示的实施例中，第一功率开关323的集电极连接至直流母线316的正端3160，第一功率开关323的发射极连接所述第一电枢电阻320。第二功率开关324的集电极连接所述第一电枢电阻320，第二功率开关324的发射极连接至直流母线316的负端3161。第三功率开关325的集电极连接至直流母线316的正端3160，第三功率开关325的发射极连接所述第二电枢电阻321。第四功率开关326的集电极连接所述第二电枢电阻321，第四功率开关326的发射极连接至直流母线316的负端3161。第五功率开关327的集电极连接至直流母线316的正端3160，第五功率开关327的发射极连接所述第三电枢电阻322。第六功率开关328的集电极连接所述第三电枢电阻322，第六功率开关328的发射极连接至直流母线316的负端3161。
在一些实施例中，第一功率开关323、第二功率开关324、第三功率开关325、第四功率开关326、第五功率开关327、第六功率开关328的栅极作为开关的控制端，可连接至机侧控制装置317的不同的控制端口，不同的控制端口独立控制功率开关。在一些实施例中，不同的控制端口可同步控制对应的功率开关。在一些实施例中，功率转换电路306设置的机侧控制装置317的工作原理及连接方式可参考图4所示的机侧控制装置317的工作方式及连接方式，在此不再赘述。
在图5所示的实施例中，当直流母线316的直流母线电压高于第一预设值时，需要采用风力发电机300的功率转换电路306的控制方法进行调节，以使风力发电机300处于并网状态下，机侧变流器314传输到直流母线316侧的有功功率与网侧变流器315输出到电网309的有功功率达到平衡。
图6为图5所示的风力发电机300的功率转换电路306的控制方法的流程图。如图 6所示，风力发电机300的功率转换路401的控制方法包括步骤S1-S3。
在步骤S1中，获取直流母线的直流母线电压。
在一些实施例中，机侧控制装置317内部设置有直流母线316的直流母线电压检测电路，可获取直流母线316的直流母线电压。在一些实施例中，机侧控制装置317可为处理器，直流母线电压检测电路可集成于处理器中，简化电路结构，节省成本。在一些实施例中，直流母线电压检测电路可通过软硬件结合的形式实现对直流母线316的直流母线电压进行检测。
在步骤S2中，若直流母线电压高于第一预设值，控制机侧变流器314的部分的功率开关导通，以使电机305的电枢电阻与直流母线316连通，泄放直流母线316的电能。
在一些实施例中，直流母线316的直流母线电压正常工作在1100V左右。在一些实施例中，第一预设值可为1180V。在其他一些实施例中，第一预设值也可设置为其他值。
在一些实施例中，当直流母线316的直流母线电压高于1180V时，机侧控制装置317控制机侧变流器314停止调制，然后控制机侧变流器314的部分的功率开关导通，以使电机305的电枢电阻与直流母线316连通，泄放直流母线316的电能。在一些实施例中，机侧控制装置317控制机侧变流器314的部分的功率开关导通的同时，控制其他功率开关截止，从而使得直流母线316的电能稳定地泄放。这里的调制指的是机侧变流器314采用SVPWM(Space Vector Pulse Width Modulation，空间矢量脉宽调制)或者SPWM(Sinusoidal Pulse Width Modulation，正弦脉宽脉宽调制)等调制方式通过控制功率开关按照程序设定的逻辑导通或关断。这里的泄放指的是导通部分的功率开关建立直流母线316与电机电阻的泄放通路。在一些实施例中，在泄放直流母线316的电能的同时，网侧控制装置318可仍控制网侧变流器315保持调制状态，首先可保证电机305不脱网运行，其次为直流母线316的能量传输提供一个电能传输通道，将直流母线316的电能传输至网侧变流器315。
在图6所示的实施例中，当风力发电机100处于并网状态下，当遇到电网105的电压突然跌落，或者高电压恢复等工况时，将机侧变流器102传输到直流母线103侧的有功功率转换为电机305的转子的动能，利用电机305的电枢电阻作为泄放电阻与直流母线316连通，以泄放直流母线316的电能，将直流母线316的直流母线电压控制在电压承受范围内，保证电机305的正常并网运行，从而保护电机305、直流母线316和风力发电机300免受损坏。与图2所示的相关技术相比，不需要增加泄放装置，能够节省风力发电机300内的空间，且不需要增加散热装置，从而降低风力发电机300的成本。
在步骤S3中，若直流母线电压低于第二预设值，控制机侧变流器314的部分的功率开关截止，以断开电机305的电枢电阻与直流母线316，结束泄放，其中，第二预设值低于第一预设值。
在一些实施例中，直流母线316的直流母线电压正常工作在1100V左右。在一些实施例中，第二预设值可为1120V。在其他一些实施例中，第二预设值也可设置为其他值。在一些实施例中，当直流母线316的直流母线电压低于1120V，机侧控制装置317控制机侧变流器314的部分的功率开关截止，以断开电机305的电枢电阻与直流母线316，结束泄放，然后控制机侧变流器314开始调制。
在一些实施例中，第一预设值与第二预设值之间的直流母线电压可为电机305的电枢电阻与直流母线316连通的泄放电压，且在直流母线电压从第一预设值降低至第二预设值的过程中，风力发电机300能够不间断并网运行，支持电网309恢复，直到电网309恢复正常。当直流母线316的直流母线电压控制在电压承受范围内时，才保证电机305的正常并网运行，从而保护电机305、直流母线316和风力发电机300免受损坏。与图2所示的相关技术相比，不用增加泄放装置，能够节省风力发电机300内的空间，且不需要增加散热装置，从而降低风力发电机300的成本。
在一些实施例中，直流母线316的直流母线电压正常工作的工作电压在本申请中不作限定。在一些实施例中，直流母线316的直流母线电压的安全电压范围值及安全电压范围值的上限值或下限值可设置为其他值，在本申请中不作限定。
图7为图6所示的风力发电机300的功率转换电路306的控制方法的步骤S2的一个实施例的流程图。如图7所示，风力发电机300的功率转换电路306的控制方法的步骤S2包括步骤S20。其中，
步骤S20、控制连接直流母线316的第一端和其中一相电枢电阻的功率开关，和连接直流母线316的第二端和其他两相中的至少一相电枢电阻的功率开关导通。直流母线316的第一端通过相应导通的功率开关与其中一相电枢电阻连通，直流母线316的第二端通过相应导通的功率开关与其他两相中的至少一相电枢电阻连通，从而直流母线316的电能通过导通的功率开关传输至电枢电阻，得到泄放。在一些实施例中，直流母线316的第一端可为正端3160。在一些实施例中，直流母线316的第二端可为负端3161。在一些实施例中，当直流母线316的直流母线电压高于第一预设值，机侧控制装置317控制机侧变流器314停止调制时，电机305不会产生有用功，此时将机侧变流器102传输到直流母线103侧的有功功率转换为电机305的转子的动能消耗掉，可将电机305的三相电枢电阻作为泄放电阻，泄放积聚在直流母线316上的电能，当有泄放电流时会加快电机305的转速，但对电机305本身的功能不会产生影响。
在一些实施例中，功率开关的控制与电枢电阻的阻值无关，电枢电阻的阻值影响的是直流母线316的直流母线电压的泄放速度，从而影响直流母线316的直流母线电压的泄放时间。在一些实施例中，多个电枢电阻组成的泄放电阻的阻值越小，泄放电流越大，产生的有功功率就越大，其泄放的速度越快，泄放的时间越短。
图8为图7所示的风力发电机300的功率转换电路306的控制方法的步骤S20的一个实施例的流程图。如图8所示，风力发电机300的功率转换电路306的控制方法的步骤S20包括步骤S200。其中，
步骤S200、若直流母线电压高于第一预设值，控制连接直流母线316的第一端和其中一相电枢电阻的功率开关，和连接直流母线316的第二端和其他一相电枢电阻的功率开关导通，以使两相电枢电阻串联后与直流母线316连通，泄放直流母线316的电能。此时控制机侧变流器314的其他功率开关截止。
在一些实施例中，直流母线316的直流母线电压正常工作在1100V左右。在一些实施例中，第一预设值可为1180V，第二预设值可为1120V。在其他一些实施例中，第一预设值与第二预设值也可设置为其他值。在一些实施例中，直流母线316的第一端可为 正端3160，直流母线316的第二端可为负端3161。结合图5与图8所示的实施例，直流母线316的第一端是正端3160，直流母线316的第二端是负端3161。
在一些实施例中，当直流母线电压高于第一预设值时，机侧控制装置317控制机侧变流器314停止调制，可控制第一功率开关323与第四功率开关326导通，以使第一电枢电阻320与第二电枢电阻321串联后与直流母线316连通，泄放直流母线316的电能。此时控制第二功率开关324、第三功率开关325、第五功率开关327与第六功率开关328截止。在一些实施例中，当直流母线电压低于第二预设值时，机侧控制装置317控制机侧变流器314的第一功率开关323与第四功率开关326截止，以断开第一电枢电阻320、第二电枢电阻321与直流母线316，结束泄放。
在另一些实施例中，当直流母线电压高于第一预设值时，机侧控制装置317控制机侧变流器314停止调制，可控制第三功率开关325与第二功率开关324导通，以使第二电枢电阻321与第一电枢电阻320串联后与直流母线316连通，泄放直流母线316的电能。此时控制第一功率开关323、第四功率开关326、第五功率开关327与第六功率开关328截止。在一些实施例中，当直流母线电压低于第二预设值时，机侧控制装置317控制机侧变流器314的第二功率开关324与第三功率开关325截止，以断开第一电枢电阻320、第二电枢电阻321与直流母线316，结束泄放。
在另一些实施例中，当直流母线电压高于第一预设值时，机侧控制装置317控制机侧变流器314停止调制，可控制第一功率开关323与第六功率开关328导通，以使第一电枢电阻320与第三电枢电阻322串联后与直流母线316连通，泄放直流母线316的电能。此时控制第二功率开关324、第三功率开关325、第四功率开关326与第五功率开关327截止。在一些实施例中，当直流母线电压低于第二预设值时，机侧控制装置317控制机侧变流器314的第一功率开关323与第六功率开关328截止，以断开第一电枢电阻320、第三电枢电阻322与直流母线316，结束泄放。
在另一些实施例中，当直流母线电压高于第一预设值时，机侧控制装置317控制机侧变流器314停止调制，可控制第五功率开关327与第二功率开关324导通，以使第三电枢电阻322与第一电枢电阻320串联后与直流母线316连通，泄放直流母线316的电能。此时控制第一功率开关323、第三功率开关325、第四功率开关326与第六功率开关328截止。在一些实施例中，当直流母线电压低于第二预设值时，机侧控制装置317控制机侧变流器314的第二功率开关324与第五功率开关327截止，以断开第一电枢电阻320、第三电枢电阻322与直流母线316，结束泄放。
在另一些实施例中，当直流母线电压高于第一预设值时，机侧控制装置317控制机侧变流器314停止调制，可控制第三功率开关325与第六功率开关328导通，以使第二电枢电阻321与第三电枢电阻322串联后与直流母线316连通，泄放直流母线316的电能。此时控制第一功率开关323、第二功率开关324、第四功率开关326与第五功率开关327截止。在一些实施例中，当直流母线电压低于第二预设值时，机侧控制装置317控制机侧变流器314的第三功率开关325与第六功率开关328截止，以断开第二电枢电阻321、第三电枢电阻322与直流母线316，结束泄放。
在另一些实施例中，当直流母线电压高于第一预设值时，机侧控制装置317控制机 侧变流器314停止调制，可控制第五功率开关327与第四功率开关326导通，以使第三电枢电阻322与第二电枢电阻321串联后与直流母线316连通，泄放直流母线316的电能。此时控制第一功率开关323、第二功率开关324、第三功率开关325与第六功率开关328截止。在一些实施例中，当直流母线电压低于第二预设值时，机侧控制装置317控制机侧变流器314的第四功率开关326与第五功率开关327截止，以断开第二电枢电阻321、第三电枢电阻322与直流母线316，结束泄放。
结合图5与图8所示的实施例中，第一电枢电阻320、第二电枢电阻321与第三电枢电阻322的阻值为R，则与直流母线316连通的由两个电枢电阻串联组成的泄放电路的阻值为2R，利用电机305的电枢电阻作为泄放电阻与直流母线316连通，以泄放直流母线316的电能，以将直流母线316的直流母线电压控制在电压承受范围内，保证电机305的正常并网运行，从而保护电机305、直流母线316和风力发电机300免受损坏。与图2所示的相关技术相比，不用增加泄放装置，能够节省风力发电机300内的空间，且不需要增加散热装置，从而降低风力发电机300的成本。
图9为直流母线316的泄放电压与电枢电阻的泄放电流的波形图。以一台全功率为3000kW的风力发电机300为例，在风力发电机300运行在额定功率时，机侧变流器314的有功功率为3000kW，当机侧变流器314传输的有功功率大于网侧变流器315传输的有功功率时，导致直流母线电压升高到第一预设值1180V时，采用上述图8所示的任一种实施方式，利用电机305的电枢电阻作为泄放电阻与直流母线316连通，将直流母线电压被拉低至第二预设值1120V，以泄放直流母线316的电能，能够将直流母线316的直流母线电压控制在电压承受范围内，保证电机305的正常并网运行，从而保护电机305和风力发电机300免受损坏。在图9中，波形700为直流母线316的泄放电压的波形图，横坐标为时间，纵坐标为电压，波形701为电枢电阻的泄放电流的波形图，横坐标为时间，纵坐标为电流，如图9所示，泄放电阻的泄放电流的峰值在2500A左右。在一些实施例中，当直流母线316的电压高于正常工作电压进行泄放时，网侧变流器315的转换正常运行，并不会受到任何影响。在一些实施例中，泄放电阻的泄放电流的峰值通过示波器测量。
图10为图7所示的风力发电机300的功率转换电路306的控制方法的步骤S20的另一个实施例的流程图。如图10所示，风力发电机300的功率转换电路306的控制方法的步骤S20包括步骤S201。其中，
步骤S201、若直流母线电压高于第一预设值，控制连接直流母线316的第一端和其中一相电枢电阻的功率开关，和连接直流母线316的第二端和其他两相电枢电阻的功率开关导通，以使连接直流母线316的第二端的其他两相电枢电阻并联后与连接直流母线316的第一端的其中一相电枢电阻串联，与直流母线316连通，泄放直流母线316的电能。此时控制机侧变流器314的其他功率开关截止。
在一些实施例中，直流母线316的直流母线电压正常工作在1100V左右。在一些实施例中，第一预设值可为1180V，第二预设值可为1120V。在其他一些实施例中，第一预设值与第二预设值也可设置为其他值，第二预设值低于第一预设值。在一些实施例中，直流母线316的第一端可为正端3160，直流母线316的第二端可为负端3161。在另一 些实施例中，直流母线316的第一端可为负端3161，直流母线316的第二端可为正端3160。
图11为图10所示的风力发电机300的功率转换电路306的控制方法的步骤S201的一个实施例的流程图。如图11所示，风力发电机300的功率转换电路306的控制方法的步骤S201包括步骤S2010。
步骤S2010、若直流母线电压高于第一预设值，控制连接直流母线316的正端3160和其中一相电枢电阻的功率开关，和连接直流母线316的负端3161和其他两相电枢电阻的功率开关导通，以使连接直流母线316的负端3161的其他两相电枢电阻并联后与连接直流母线316的正端3160的其中一相电枢电阻串联，与直流母线316连通，泄放直流母线316的电能。此时控制机侧变流器314的其他功率开关截止。
结合图5与图11所示的实施例，直流母线316的第一端是正端3160，直流母线316的第二端是负端3161。
在一些实施例中，当直流母线电压高于第一预设值时，机侧控制装置317控制机侧变流器314停止调制，可控制第一功率开关323和第四功率开关326及第六功率开关328导通，以使第二电枢电阻321与第三电枢电阻322并联后与第一电枢电阻320串联，与直流母线316连通，泄放直流母线316的电能。此时控制第二功率开关324、第三功率开关325与第五功率开关327截止。在一些实施例中，当直流母线电压低于第二预设值时，机侧控制装置317控制机侧变流器314的第一功率开关323、第四功率开关326与第六功率开关328截止，以断开第一电枢电阻320、第二电枢电阻321、第三电枢电阻322与直流母线316，结束泄放。
在另一些实施例中，当直流母线电压高于第一预设值时，机侧控制装置317控制机侧变流器314停止调制，可控制第三功率开关325和第二功率开关324及第六功率开关328导通，以使第一电枢电阻320与第三电枢电阻322并联后与第二电枢电阻321串联，与直流母线316连通，泄放直流母线316的电能。此时控制第一功率开关323、第四功率开关326与第五功率开关327截止。在一些实施例中，当直流母线电压低于第二预设值时，机侧控制装置317控制机侧变流器314的第二功率开关324、第三功率开关325与第六功率开关328截止，以断开第一电枢电阻320、第二电枢电阻321、第三电枢电阻322与直流母线316，结束泄放。
在另一些实施例中，当直流母线电压高于第一预设值时，机侧控制装置317控制机侧变流器314停止调制，可控制第五功率开关327和第二功率开关324及第四功率开关326导通，以使第一电枢电阻320与第二电枢电阻321并联后与第三电枢电阻322串联，与直流母线316连通，泄放直流母线316的电能。此时控制第一功率开关323、第三功率开关325与第六功率开关328截止。在一些实施例中，当直流母线电压低于第二预设值时，机侧控制装置317控制机侧变流器314的第二功率开关324、第四功率开关326与第五功率开关327截止，以断开第一电枢电阻320、第二电枢电阻321、第三电枢电阻322与直流母线316，结束泄放。
结合图5与图11所示的实施例中，第一电枢电阻320、第二电枢电阻321与第三电枢电阻322的阻值为R，则与直流母线316连通的电枢电阻的阻值为1.5R。图8所示的 实施例相对于图11所示的实施例来说，泄放速度快，泄放时间短。图11所示的实施例相对于图8所示的实施例来说，与直流母线316连通的电枢电阻的阻值较小。在图11所示的任一种实施方式，利用电机305的两相电枢电阻并联后与其他一相电枢电阻串联作为泄放电阻与直流母线316连通，以泄放直流母线316的电能，能够将直流母线316的直流母线电压控制在电压承受范围内，保证电机305的正常并网运行，从而保护电机305、直流母线316和风力发电机300免受损坏。与图2所述的相关技术相比，不需要增加制动装置，能够节省风力发电机300内的空间，且不需要增加散热装置，从而降低风力发电机300的成本。
图12为图10所示的风力发电机的功率转换电路的控制方法的步骤S201的另一个实施例的流程图。如图12所示，风力发电机300的功率转换电路306的控制方法的步骤S201包括步骤S2011。
步骤S2011、若直流母线电压高于第一预设值，控制连接直流母线316的负端3161和其中一相电枢电阻的功率开关，和连接直流母线316的正端3160和其他两相电枢电阻的功率开关导通，以使连接直流母线316的正端3160的其他两相电枢电阻并联后与连接直流母线316的负端3161的其中一相电枢电阻串联，与直流母线316连通，泄放直流母线316的电能。此时控制机侧变流器314的其他功率开关截止。
结合图5与图12所示的实施例中，直流母线316的第一端为负端3161，直流母线316的第二端为正端3160。
在一些实施例中，当直流母线电压高于第一预设值时，机侧控制装置317控制机侧变流器314停止调制，可控制第一功率开关323、第三功率开关325与第六功率开关328导通，以使第一电枢电阻320与第二电枢电阻321并联后与第三电枢电阻322串联，与直流母线316连通，泄放直流母线316的电能。此时控制第二功率开关324、第四功率开关326与第五功率开关327截止。在一些实施例中，当直流母线电压低于第二预设值时，机侧控制装置317控制机侧变流器314的第一功率开关323、第三功率开关325与第六功率开关328截止，以断开第一电枢电阻320、第二电枢电阻321、第三电枢电阻322与直流母线316，结束泄放。
在另一些实施例中，当直流母线电压高于第一预设值时，机侧控制装置317控制机侧变流器314停止调制，可控制第一功率开关323、第五功率开关327与第四功率开关326导通，以使第一电枢电阻320与第三电枢电阻322并联后与第二电枢电阻321串联，与直流母线316连通，泄放直流母线316的电能。此时控制第二功率开关324、第三功率开关325与第六功率开关328截止。在一些实施例中，当直流母线电压低于第二预设值时，机侧控制装置317控制机侧变流器314的第一功率开关323、第四功率开关326与第五功率开关327截止，以断开第一电枢电阻320、第二电枢电阻321、第三电枢电阻322与直流母线316，结束泄放。
在另一些实施例中，当直流母线电压高于第一预设值时，机侧控制装置317控制机侧变流器314停止调制，可控制第三功率开关325、第五功率开关327与第一功率开关4013导通，第二电枢电阻321与第三电枢电阻322并联后与第一电枢电阻320串联，与直流母线316连通，泄放直流母线316的电能。此时控制第二功率开关324、第四功率 开关326与第六功率开关328截止。在一些实施例中，当直流母线电压低于第二预设值时，机侧控制装置317控制机侧变流器314的第一功率开关323、第三功率开关325与第五功率开关327截止，以断开第一电枢电阻320、第二电枢电阻321、第三电枢电阻322与直流母线316，结束泄放。
结合图5与图12所示的实施例中，第一电枢电阻320、第二电枢电阻321与第三电枢电阻322的阻值为R，则与直流母线316连通的电枢电阻的阻值为1.5R。图8所示的实施例相对于图12所示的实施例来说，泄放速度快，泄放时间短。图12所示的实施例相对于图8所示的实施例来说，与直流母线316连通的电枢电阻的阻值较小。图12所示的实施例相对于图11所示的实施例来说，与直流母线316连通的电枢电阻的阻值相同，泄放速度与泄放时间相同。图12所示的任一种实施方式，利用电机305的两相电枢电阻并联后与其他一相电枢电阻串联作为泄放电阻与直流母线316连通，以泄放直流母线316的电能，能够将直流母线316的直流母线电压控制在电压承受范围内，保证电机305的正常并网运行，从而保护电机305、直流母线316和风力发电机300免受损坏。并且与图2所示的相关技术相比，不需要增加制动装置，能够节省风力发电机300内的空间，且不需要增加散热装置，从而降低风力发电机300的成本。
图13为图4所示的本申请的风力发电机400的另一个实施例的部分电路示意图。如图13所示的风力发电机400与图5所示的风力发电机300相似。在图13所示的实施例中，风力发电机400增加制动装置401，其中，制动装置401包括制动电阻402以及与制动电阻402串联的制动开关403。制动装置401的一端连接至直流母线411的正端4110，制动装置401的另一端连接至直流母线411的负端4111。风力发电机400包括电机404与功率转换电路405，其中，电机404包括三相电枢电阻，三相电枢电阻包括第一电枢电阻407、第二电枢电阻408与第三电枢电阻409，功率转换电路405包括机侧变流器410以及与机侧变流器410连接的直流母线411，其直流母线411包括正端4110与负端4111，制动装置401连接于直流母线411的正端4110与负端4111之间。在一些实施例中，机侧变流器410包括第一功率开关412、第二功率开关413、第三功率开关414、第四功率开关415、第五功率开关416与第六功率开关417。图13所示的电机404、功率转换电路405与图5所示的电机305、功率转换电路306相似，其工作原理及连接方式可参见图5所示的实施例，在此不再赘述。
在一些实施例中，制动装置401的控制端与功率开关的控制端连接至机侧控制装置(未图示)的不同的控制端口，可实现同步导通功率开关与制动开关403。在其他一些实施例中，功率转换电路405还包括制动控制器(未图示)，电连接制动装置401的制动开关403，控制制动开关403。在一些实施例中，制动控制器(未图示)可包括任何合适的可编程电路或者装置，例如数字信号处理器(Digital Signal Processor，DSP)、现场可编程门阵列(Field Programmable Gate Array，FPGA)、可编程逻辑控制器(Programmable Logic Controller，PLC)以及专用集成电路(Application Specific Integrated Circuit，ASIC)等。在一些实施例中，制动控制器可通过软硬件结合的形式实现对制动开关403的控制。在一些实施例中，制动控制器与机侧控制装置317可同步控制。
在一些实施例中，制动电阻402可为小阻值的制动电阻，制动电阻402可作为连接 在直流母线411上的耗能单元，当检测到直流母线411的直流母线电压高于正常工作电压时消耗掉多余的能量。与图2所示的相关技术相比，对于2.5MW全功率的风力发电机400，可将原来需要使用两只的泄放电阻202减少至一只，节省了风力发电机400内的空间，且对于小功率的制动电阻402产生的热量很小，不需要配置散热装置，从而降低风力发电机400的成本。
在另一些实施例中，在直流母线411上连接额外的储能单元，当检测到直流母线411的直流母线电压高于正常工作电压时转移多余的能量，故障恢复后将多存储的能量馈入电网，例如，储能单元可为电池等。在其他一些实施例中，也可增加网侧变流器(未图示)的容量，例如增加多个网侧变流器并行工作。
图14为图13所示的风力发电机400的功率转换电路405的控制方法一个实施例的流程图。相比较于图6所示的实施例，图14所示的风力发电机400的功率转换路405的控制方法进一步包括：
若直流母线电压高于第一预设值，控制制动开关403导通，以使制动电阻402与直流母线411连通，泄放直流母线411的电能；
若直流母线电压低于第二预设值，控制制动开关403截止，以断开制动电阻402与直流母线411，结束泄放，其中，第二预设值低于第一预设值。
具体地，如图14所示，控制方法包括步骤S1、S4、S5。其中，
步骤S1、获取直流母线411的直流母线电压。与图6所示的控制方法的步骤S1类似，可参考上文图6所示的实施例，在此不再赘述。
步骤S4、若直流母线电压高于第一预设值，控制机侧变流器410的部分的功率开关导通，控制制动开关403导通，以使电机404的电枢电阻、制动电阻402与直流母线411连通，泄放直流母线411的电能。控制机侧变流器410的部分的功率开关导通的方法与图6所示的对应方法类似，可参考上文图6所示的实施例，在此不再赘述。在一些实施例中，在直流母线电压高于第一预设值时，控制机侧变流器410的部分的功率开关导通时，可同时控制制动开关403导通。图14所示的实施例中增加了泄放电阻，不仅利用电枢电阻，还利用制动电阻402作为泄放电阻与直流母线411连通，以泄放直流母线411的电能，加快了泄放速度，缩短了泄放时间。
步骤S5、若直流母线电压低于第二预设值，控制机侧变流器410的部分的功率开关截止，控制制动开关403截止，以断开电机404的电枢电阻、制动电阻402与直流母线411，结束泄放，其中，第二预设值低于第一预设值。在图14所示的实施例中，控制机侧变流器410的部分的功率开关截止的方法与图6所示的对应方法也类似，可参考上文图6所示的实施例，在此不再赘述。在一些实施例中，在直流母线电压低于第二预设值时，控制机侧变流器410的部分的功率开关截止时，可同时控制制动开关403截止，以断开电机404的电枢电阻、制动开关403与直流母线，结束泄放。
图15为直流母线411的泄放电压、电枢电阻的泄放电流及制动电阻402的泄放电流的波形图。以一台全功率的3300kW的风力发电机400为例，在风力发电机400运行在额定功率时，机侧变流器410的有功功率为3300kW，当机侧变流器410传输的有功功率大于网侧变流器(未图示)传输的有功功率导致直流母线电压升高到第一预设值 1180V时，结合图14与图11或图12中任一种实施方式，将电机404的电枢电阻与制动电阻402作为泄放电阻与直流母线411连通，将直流母线电压被拉低至第二预设值1120V，以泄放直流母线411的电能，能够将直流母线411的直流母线电压控制在电压承受范围内，能够保证电机404的正常并网运行，从而保护电机404、直流母线414和风力发电机400免受损坏。与图2所示的相关技术相比，减少制动装置401的数量能够节省风力发电机400内的空间，且不需要增加散热装置，从而降低风力发电机400的成本。在图15中，波形702为直流母线411的泄放电压的波形图，横坐标为时间，纵坐标为电压，波形703为电枢电阻的泄放电流的波形图，横坐标为时间，纵坐标为电流，波形704为制动电阻402的泄放电流的波形图，横坐标为时间，纵坐标为电流。如图15所示，制动电阻402的泄放电压的峰值在1700A左右，电枢电阻的泄放电流的峰值在2900A左右。在一些实施例中，网侧变流器(未图示)的转换正常运行，并不会受到任何影响。在一些实施例中，制动电阻402的泄放电压的峰值与电枢电阻的泄放电流的峰值可采用示波器测量得到。
在一些实施例中，根据直流母线411的容值以及风力发电机400的功率值，选择适当的上述任一种实施方式。在一些实施例中，当电机404的功率小，直流母线411的容值不大时，可不需要增加额外的制动装置401的制动电阻402进行泄放。当电机404的功率很大，直流母线411的容值很大时，则需要增加额外的制动装置401的制动电阻402进行泄放。
与前述种风力发电机300的功率转换电路306的控制方法的实施例相对应，本申请还提供了一种风力发电机300的功率转换电路306的控制装置的实施例。
图16为本申请的风力发电机的功率转换电路的控制装置500的一个实施例的原理图。在一些实施例中，控制装置500包括一个或多个处理器501，用于实现前述风力发电机的功率转换电路的控制方法的实施例中任一项的风力发电机的功率转换电路的控制方法。
本申请的风力发电机的功率转换电路的控制装置500的实施例可应用在风力发电机上。控制装置500的实施例可通过软件实现，也可通过硬件或者软硬件结合的方式实现。以软件实现为例，作为一个逻辑意义上的装置，是通过其所在风力发电机的处理器501将非易失性存储器中对应的计算机程序指令读取到内存中运行形成的。从硬件层面而言，如图16所示，为本申请的控制装置500所在风力发电机的一种硬件结构图，除了图16所示的处理器501、内存、网络接口、以及非易失性存储器之外，实施例中装置所在的风力发电机通常根据该风力发电机的实际功能，还可包括其他硬件，对此不再赘述。
在一些实施例中，处理器501可为中央处理单元(Central Processing Unit，CPU)，还可为其他通用处理器、数字信号处理器(Digital Signal Processor，DSP)、专用集成电路(Application Specific Integrated Circuit，ASIC)、现场可编程门阵列(Field-Programmable Gate Array，FPGA)或者其他可编程逻辑器件、分立门或者晶体管逻辑器件、分立硬件组件等。通用处理器可为微处理器或者该处理器501也可为任何常规的处理器等。在此不再赘述。
在一些实施例中，图16所示的控制装置500可参考上文中图4所示的控制装置307，在此不再赘述。
图17为本申请的风力发电机600的一个实施例的原理图。如图17所示，风力发电机的600包括功率转换电路601、电机602、及上述图16所示的的风力发电机的功率转换电路的控制装置500。
在一些实施例中，功率转换电路601与电机602连接，用于转换电机602输出的电能，功率转换电路601包括机侧变流器6010、直流母线6011和网侧变换器6012，机侧变流器6010电连接电机602，直流母线6011与机侧变流器6010电连接，网侧变换器6012与直流母线6011电连接。在一些实施例中，控制装置600电连接机侧变流器6010。
在一些实施例中，控制装置500包括一个或多个处理器501，用于实现前述种风力发电机的功率转换电路的控制方法的实施例中任一项的风力发电机的功率转换电路的控制方法。在一些实施例中，控制装置500可控制机侧变流器6010的部分的功率开关导通，以使电机602的电枢电阻作为泄放电阻与直流母线6011连通，泄放直流母线6011的电能，在直流母线电压升高时，将直流母线电压控制在电压承受范围内，保证电机602的正常并网运行，从而保护电机602、直流母线6011和风力发电机600免受损坏。
在一些实施例中，图17所示的功率转换电路601、机侧变流器6010、网侧变换器6012可参考上文中图4所示的功率转换电路306、机侧变流器314、网侧变换器315，在此不再赘述。
上述控制装置中各个单元的功能和作用的实现过程具体详见上述方法中对应步骤的实现过程，在此不再赘述。
对于装置实施例而言，由于其基本对应于方法实施例，所以相关之处参见方法实施例的部分说明即可。以上所描述的装置实施例仅仅是示意性的，其中所述作为分离部件说明的单元可为或者也可不是物理上分开的，作为单元显示的部件可为或者也可不是物理单元，即可位于一个地方，或者也可分布到多个网络单元上。可根据实际的需要选择其中的部分或者全部模块来实现本申请方案的目的。本领域普通技术人员在不付出创造性劳动的情况下，即可理解并实施。
本申请还提供一种计算机可读存储介质，其上存储有计算机程序，该程序被处理器501执行时实现第一方面任一项的风力发电机控制方法。在一些实施例中，计算机可读存储介质可为前述任一实施例所述的风力发电机的内部存储单元，例如硬盘或内存。计算机可读存储介质也可为风力发电机的外部存储设备，例如所述设备上配备的插接式硬盘、智能存储卡(Smart Media Card，SMC)、SD卡、闪存卡(Flash Card)等。进一步的，计算机可读存储介质还可既包括风力发电机的内部存储单元也包括外部存储设备。计算机可读存储介质用于存储所述计算机程序以及所述风力发电机所需的其他程序和数据，还可用于暂时地存储已经输出或者将要输出的数据。
以上所述仅为本申请的较佳实施例，并不用以限制本申请，凡在本申请的精神和原则之内，所做的任何修改、等同替换、改进等，均应包含在本申请保护的范围之内。

Claims (10)

  1. 一种风力发电机的功率转换电路的控制方法，所述风力发电机包括与所述功率转换电路连接的电机，所述功率转换电路包括与所述电机连接的机侧变流器及与所述机侧变流器连接的直流母线，其特征在于，所述控制方法包括：
    获取所述直流母线的直流母线电压；
    若所述直流母线电压高于第一预设值，控制所述机侧变流器的部分的功率开关导通，以使所述电机的电枢电阻与所述直流母线连通，泄放所述直流母线的电能；
    若所述直流母线电压低于第二预设值，控制所述机侧变流器的部分的所述功率开关截止，以断开所述电机的所述电枢电阻与所述直流母线，结束泄放；
    所述第二预设值低于所述第一预设值。
  2. 根据权利要求1所述的控制方法，其特征在于，所述电机包括星型连接的三相所述电枢电阻；
    若所述直流母线电压高于所述第一预设值，控制所述机侧变流器的部分的所述功率开关导通，包括：
    控制连接所述直流母线的第一端和其中一相所述电枢电阻的功率开关，和连接所述直流母线的第二端和其他两相中的至少一相所述电枢电阻的功率开关导通。
  3. 根据权利要求2所述的控制方法，其特征在于，控制连接所述直流母线的第一端和其中一相所述电枢电阻的功率开关，和连接所述直流母线的第二端和其他两相中的至少一相所述电枢电阻的功率开关导通，包括：
    若所述直流母线电压高于所述第一预设值，控制连接所述直流母线的第一端和其中一相所述电枢电阻的功率开关，和连接所述直流母线的第二端和其他一相所述电枢电阻的功率开关导通，以使两相所述电枢电阻串联后与所述直流母线连通，泄放所述直流母线的电能。
  4. 根据权利要求2所述的控制方法，其特征在于，控制连接所述直流母线的第一端和其中一相所述电枢电阻的功率开关，和连接所述直流母线的第二端和其他两相中的至少一相所述电枢电阻的功率开关导通，包括：
    若所述直流母线电压高于所述第一预设值，控制连接所述直流母线的第一端和其中一相所述电枢电阻的功率开关，和连接所述直流母线的第二端和其他两相所述电枢电阻的功率开关导通，以使连接所述直流母线的第二端的其他两相所述电枢电阻并联后与连接所述直流母线的第一端的其中一相所述电枢电阻串联，与所述直流母线连通，泄放所述直流母线的电能。
  5. 根据权利要求4所述的控制方法，其特征在于，所述直流母线的第一端为正端，所述直流母线的第二端为负端；
    控制连接所述直流母线的第一端和部分所述电枢电阻的功率开关，和连接所述直流母线的第二端和其他至少一相所述电枢电阻的功率开关导通，包括：
    若所述直流母线电压高于所述第一预设值，控制连接所述直流母线的正端和其中一 相所述电枢电阻的功率开关，和连接所述直流母线的负端和其他两相所述电枢电阻的功率开关导通，以使连接所述直流母线的负端的其他两相所述电枢电阻并联后与连接所述直流母线的正端的其中一相所述电枢电阻串联，与所述直流母线连通，泄放所述直流母线的电能。
  6. 根据权利要求4所述的控制方法，其特征在于，所述直流母线的第一端为负端，所述直流母线的第二端为正端；
    控制连接所述直流母线的第一端和部分所述电枢电阻的功率开关，和连接所述直流母线的第二端和其他至少一相所述电枢电阻的功率开关导通，包括：
    若所述直流母线电压高于所述第一预设值，控制连接所述直流母线的负端和其中一相所述电枢电阻的功率开关，和连接所述直流母线的正端和其他两相所述电枢电阻的功率开关导通，以使连接所述直流母线的正端的其他两相所述电枢电阻并联后与连接所述直流母线的负端的其中一相所述电枢电阻串联，与所述直流母线连通，泄放所述直流母线的电能。
  7. 根据权利要求1至6中任一项所述的控制方法，其特征在于，所述风力发电机还包括连接于所述直流母线的正端与负端之间的制动单元，所述制动单元包括制动电阻以及与所述制动电阻串联的制动开关；控制方法包括：
    若所述直流母线电压高于所述第一预设值，控制所述制动开关导通，以使所述制动电阻与所述直流母线连通，泄放所述直流母线的电能；
    若所述直流母线电压低于所述第二预设值，控制所述制动开关截止，以断开所述制动电阻与所述直流母线，结束泄放；
    所述第二预设值低于所述第一预设值。
  8. 一种计算机可读存储介质，其上存储有计算机程序，其特征在于，该程序被处理器执行时实现权利要求1至7任一项所述的风力发电机的功率转换电路的控制方法。
  9. 一种风力发电机的功率转换电路的控制装置，其特征在于，包括一个或多个处理器，用于实现如权利要求1至7中任一项所述的风力发电机的功率转换电路的控制方法。
  10. 一种风力发电机，其特征在于，包括：
    电机；
    功率转换电路，与所述电机连接，用于转换所述电机输出的电能，所述功率转换电路包括机侧变流器、直流母线和网侧变换器，所述机侧变流器电连接所述电机，所述直流母线与所述机侧变流器电连接，所述网侧变换器与所述直流母线电连接；以及
    权利要求9所述的风力发电机的功率转换电路的控制装置，所述控制装置电连接所述机侧变流器。
PCT/CN2021/093161 2020-06-16 2021-05-11 风力发电机及其功率转换电路的控制方法和装置 WO2021254031A1 (zh)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN202010550631.6 2020-06-16
CN202010550631.6A CN111711389B (zh) 2020-06-16 2020-06-16 风力发电机及其功率转换电路的控制方法和装置

Publications (1)

Publication Number Publication Date
WO2021254031A1 true WO2021254031A1 (zh) 2021-12-23

Family

ID=72540728

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2021/093161 WO2021254031A1 (zh) 2020-06-16 2021-05-11 风力发电机及其功率转换电路的控制方法和装置

Country Status (2)

Country Link
CN (1) CN111711389B (zh)
WO (1) WO2021254031A1 (zh)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111711389B (zh) * 2020-06-16 2022-03-25 上海电气风电集团股份有限公司 风力发电机及其功率转换电路的控制方法和装置

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005042632A (ja) * 2003-07-23 2005-02-17 Daikin Ind Ltd 流体機械
CN201774451U (zh) * 2010-08-26 2011-03-23 哈尔滨九洲电气股份有限公司 双馈风电变流器直流卸荷电路
CN102324754A (zh) * 2011-08-26 2012-01-18 天津理工大学 基于储能装置的双馈型风力发电机低电压穿越控制系统
CN105429358A (zh) * 2015-11-30 2016-03-23 北京赛思亿电气科技有限公司 可作为电动机启动的船舶轴带发电系统及其控制方法
US20200067400A1 (en) * 2018-08-22 2020-02-27 Texas Instruments Incorporated Gate driver controller and associated discharge method
CN111711389A (zh) * 2020-06-16 2020-09-25 上海电气风电集团股份有限公司 风力发电机及其功率转换电路的控制方法和装置

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FI112733B (fi) * 1994-09-30 2003-12-31 Kone Corp Menetelmä ja laitteisto tahtimoottorin jarruttamiseksi
JP2004015892A (ja) * 2002-06-05 2004-01-15 Toshiba Corp インバータの制御装置及び電気自動車
CN101841292B (zh) * 2010-06-07 2012-01-11 苏州能健电气有限公司 风力发电变桨控制系统直流电机驱动器
JP5955414B2 (ja) * 2012-12-13 2016-07-20 三菱電機株式会社 モータ制御装置
CN205141698U (zh) * 2015-09-29 2016-04-06 三一重型能源装备有限公司 双馈风力发电系统

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005042632A (ja) * 2003-07-23 2005-02-17 Daikin Ind Ltd 流体機械
CN201774451U (zh) * 2010-08-26 2011-03-23 哈尔滨九洲电气股份有限公司 双馈风电变流器直流卸荷电路
CN102324754A (zh) * 2011-08-26 2012-01-18 天津理工大学 基于储能装置的双馈型风力发电机低电压穿越控制系统
CN105429358A (zh) * 2015-11-30 2016-03-23 北京赛思亿电气科技有限公司 可作为电动机启动的船舶轴带发电系统及其控制方法
US20200067400A1 (en) * 2018-08-22 2020-02-27 Texas Instruments Incorporated Gate driver controller and associated discharge method
CN111711389A (zh) * 2020-06-16 2020-09-25 上海电气风电集团股份有限公司 风力发电机及其功率转换电路的控制方法和装置

Also Published As

Publication number Publication date
CN111711389B (zh) 2022-03-25
CN111711389A (zh) 2020-09-25

Similar Documents

Publication Publication Date Title
CA2810593C (en) Double fed induction generator (dfig) converter and method for improved grid fault ridethrough
EP2811157B1 (en) Methods for operating wind turbine system having dynamic brake
EP3096005B1 (en) Limit for derating scheme used in wind turbine control
US9231509B2 (en) System and method for operating a power generation system within a power storage/discharge mode or a dynamic brake mode
CN103368187A (zh) 基于改进风力发电机组下的无功协调控制方法
WO2021254031A1 (zh) 风力发电机及其功率转换电路的控制方法和装置
CA2901713C (en) System and method for improving reactive current response time in a wind turbine
EP3629440B1 (en) System and method for controlling uninterruptible power supply of electrical power systems
US8451573B1 (en) Overvoltage protection device for a wind turbine and method
BR112019022448B1 (pt) Sistema de geração de energia e método para melhorar a produção de energia elétrica por um sistema de geração de energia
BR102013010236A2 (pt) Método de proteção contra sobretensão e sistema
CN103630838A (zh) 一种双馈发电机对拖温升试验方法及装置
CN113819000A (zh) 操作连接到串联补偿传输系统的基于逆变器的资源的方法
US20150263508A1 (en) System and method for detecting islanding of electrical machines and protecting same
ES2909344T3 (es) Sistema y método para evitar el colapso de tensión de los sistemas de potencia de turbinas eólicas conectadas a una red eléctrica
EP3651350A1 (en) System and method for wind power generation and transmission in electrical power systems
CN110870156B (zh) 针对风电场停机之后的快速连接的操作风电场的系统和方法
EP3487066B1 (en) System and method for operating a doubly fed induction generator system to reduce harmonics
CN112242705A (zh) 用于在可再生能功率系统中降低振荡的系统和方法
Anggito et al. Novel TSC-based Voltage Controller for a Stand-Alone Induction Generator
Desingu et al. Thermal loading of multi-megawatt medium-voltage power converters serving to variable speed large pumped storage units
von den Hoff et al. Design and Evaluation of a Battery-Supported Electric Drivetrain for Kite-Based High-Altitude Wind Energy Conversion
CN103630771A (zh) 一种风力发电用变频器全功率的测试平台
EP3506489B1 (en) System and method for controlling switching device temperature of electrical power systems
Yan et al. An experimental system for LVRT of direct-drive PMSG wind generation system

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 21826261

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 21826261

Country of ref document: EP

Kind code of ref document: A1

32PN Ep: public notification in the ep bulletin as address of the adressee cannot be established

Free format text: NOTING OF LOSS OF RIGHTS PURSUANT TO RULE 112(1) EPC (EPO FORM 1205A DATED 12/06/2023)

122 Ep: pct application non-entry in european phase

Ref document number: 21826261

Country of ref document: EP

Kind code of ref document: A1