Wind power converter device

Abstract

A wind power converter device includes: a plurality of grid-side converters, a plurality of machine-side converters, and a DC bus module. The grid-side converters are arranged under the tower of the wind power system, and each includes a grid-side output port electrically coupled to the power grid and first and second DC input ports, and the second and first DC input ports respectively included in any two adjacent grid-side converters are connected in series. The machine-side converters are arranged on the tower of the wind power system, and each includes a machine-side input port electrically coupled to the generator device and first and second DC output ports, and the second and first DC output ports respectively included in any two adjacent machine-side converters are connected in series. The DC bus module includes a plurality of DC buses electrically coupled between the grid-side converters and the machine-side converters. The plurality of DC buses include a positive DC bus, a negative DC bus, and at least one intermediate DC bus, and the cross-sectional area of the conductor of the intermediate DC bus is less than 30% of the cross-sectional area of the conductor of the positive or negative DC bus.

Description

Technical Field

[0001] The present invention relates to a power technology, and particularly to a wind power converter device. Background Art

[0002] With the continuous development of renewable energy, the wind power converter, as the core part of the wind power generation device, has also been continuously improved by technicians. In the fields of electric drive frequency converters and power generation converters, multiple converters may be used according to the increase in system capacity. However, when using multiple converters, multiple long-distance DC buses are often required for voltage transmission. If the cost of the DC energy transmission part cannot be reduced, the overall efficiency of the converter cannot be improved. In addition, when the motor and the generator are far apart, that is, when the converter on the generator side and the converter on the motor side are far apart, multiple converters are also often used and multiple long-distance DC buses are required for voltage transmission. If the cost of the DC energy transmission part cannot be reduced, the overall efficiency of the converter cannot be improved. Moreover, since the service life of the wind power generation device is usually designed to be relatively long, for example, twenty years, if the reliability of each converter in the wind power generation device cannot be improved, the wind power generation device may often malfunction and need to be shut down for maintenance frequently, resulting in the inability to reduce the power generation production cost. In addition, when the wind power generation device uses multiple converters, if any one of the converters fails, it may lead to insufficient power generation of the wind power generation device, resulting in poor stability of the wind power generation device.

[0003] Therefore, how to design a new wind power converter device to solve the above problems is an urgent problem to be solved in this industry. Summary of the Invention

[0004] Accordingly, one aspect of the present invention is to provide a wind power converter device, comprising: a plurality of grid-side converters, a plurality of machine-side converters, and a DC bus module. The grid-side converters are disposed under the tower of the wind power system, and each includes a plurality of grid-side output ports electrically coupled to the power grid, a first DC input port, and a second DC input port, and the second DC input port of one of any two adjacent grid-side converters is connected in series with the first DC input port of the other. The machine-side converters are disposed on the tower of the wind power system, and each includes a machine-side input port electrically coupled to the generator device, a first DC output port, and a second DC output port, and the second DC output port of one of any two adjacent machine-side converters is connected in series with the first DC output port of the other. The DC bus module includes a plurality of DC buses electrically coupled between the grid-side converters and the machine-side converters. The plurality of DC buses include a positive DC bus, a negative DC bus, and at least one intermediate DC bus between the positive DC bus and the negative DC bus, and the cross-sectional area of the conductor of at least one intermediate DC bus is less than 30% of the cross-sectional area of the conductor of the positive DC bus or the negative DC bus.

[0005] Optionally, the number of the grid-side converters and the number of the machine-side converters are both n, where n≥2; the first DC input port of the first grid-side converter is electrically coupled to the first DC output port of the first machine-side converter through the positive DC bus; the second DC input port of the nth grid-side converter is electrically coupled to the second DC output port of the nth machine-side converter through the negative DC bus; and the second DC input port of the (n - 1)th grid-side converter and the second DC output port of the (n - 1)th machine-side converter are both electrically coupled through the intermediate DC bus.

[0006] Optionally, the number of the grid-side converters is n and the number of the machine-side converters is 2n, and the grid-side converter further includes a first DC midpoint, where n≥1; the first DC input end of the first grid-side converter is electrically coupled to the first DC output end of the first machine-side converter through the positive DC bus; the second DC input port of the nth grid-side converter is electrically coupled to the second DC output port of the 2nth machine-side converter through the negative DC bus; and between the first DC midpoint of the nth grid-side converter and the first DC output port of the 2nth machine-side converter, and between the second DC input port of the (n - 1)th grid-side converter and the first DC output port of the (2n - 1)th machine-side converter are electrically coupled through the intermediate DC bus.

[0007] Optionally, the number of grid-side converters is 2n and the number of machine-side converters is n, and the machine-side converters further include a second DC midpoint, where n≥1; wherein, the first DC input terminal of the first grid-side converter is electrically coupled to the first DC output terminal of the first machine-side converter through a positive DC bus; the second DC input port of the 2nth grid-side converter is electrically coupled to the second DC output port of the nth machine-side converter through a negative DC bus; and between the first DC input port of the 2nth grid-side converter and the second DC midpoint of the nth machine-side converter, and between the first DC input port of the (2n - 1)th grid-side converter and the second DC output port of the nth machine-side converter are both electrically coupled through an intermediate DC bus.

[0008] Another aspect of the present invention is to provide a wind power converter device, including: a plurality of grid-side converters, a plurality of machine-side converters, a DC bus module, and at least one passive circuit protection element. The plurality of grid-side converters are arranged under the tower of the wind power system, and each includes a plurality of grid-side output ports electrically coupled to the power grid, a first DC input terminal, and a second DC input terminal, and the second DC input terminal of any two adjacent grid-side converters is connected in series with the first DC input terminal of the other. The plurality of machine-side converters are arranged on the tower of the wind power system, and each includes a machine-side input port electrically coupled to the generator device, a first DC output terminal, and a second DC output terminal, and the second DC output terminal of any two adjacent machine-side converters is connected in series with the first DC output terminal of the other; the DC bus module includes a plurality of DC buses and is electrically coupled between the grid-side converters and the machine-side converters. The passive circuit protection element is arranged in at least one power transmission path established by the corresponding grid-side converter, the corresponding machine-side converter, and the DC bus module and located between the power grid and the generator device, wherein electric energy is transmitted between the power grid and the generator device through the power transmission path, and the passive circuit protection element has a preset current value. When the current on the power transmission path corresponding to the passive circuit protection element exceeds the preset current value of the passive circuit protection element, the passive circuit protection element is in an open circuit state.

[0009] Optionally, the passive circuit protection element is a fuse.

[0010] Optionally, the passive circuit protection element is arranged on the corresponding DC bus, or on the connection line between at least one grid-side output port of the corresponding grid-side converter and the power grid, or on the connection line between at least one machine-side output port of the corresponding machine-side converter and the generator device.

[0011] Another aspect of the present invention is to provide a wind power converter device, comprising: a plurality of grid-side converters, a plurality of machine-side converters, a DC bus module, at least one active circuit protection element, and at least one detection circuit. The plurality of grid-side converters are arranged under the tower of the wind power system, and each includes a plurality of grid-side output ports electrically coupled to the power grid, a first DC input port, and a second DC input port, and the second DC input port of one of any two adjacent grid-side converters is connected in series with the first DC input port of the other. The plurality of machine-side converters are arranged on the tower of the wind power system, and each includes a machine-side input port electrically coupled to the generator device, a first DC output port, and a second DC output port, and the second DC output port of one of any two adjacent machine-side converters is connected in series with the first DC output port of the other. The DC bus module includes a plurality of DC buses and is electrically coupled between the grid-side converters and the machine-side converters. The active circuit protection element is arranged in at least one power transmission path established by the corresponding grid-side converter, the corresponding machine-side converter, and the DC bus module and located between the power grid and the generator device, wherein electric energy is transmitted between the power grid and the generator device through the power transmission path. The detection circuit is arranged in the corresponding power transmission path. The detection circuit is used to detect whether the electric energy on the corresponding power transmission path is abnormal, and when an abnormality is detected, an abnormal signal corresponding thereto is output, so that the active circuit protection element on the corresponding power transmission path is switched to an open state according to the abnormal signal.

[0012] Optionally, the active circuit protection element is a relay or a switching element, and the detection circuit is a current sensor.

[0013] Optionally, the active circuit protection element is arranged on the corresponding DC bus, or on the connection line between at least one grid-side output port of the corresponding grid-side converter and the power grid, or on the connection line between at least one machine-side output port of the corresponding machine-side converter and the generator device.

[0014] Optionally, the detection circuit is arranged on the corresponding DC bus, or on the connection line between at least one grid-side output port of the corresponding grid-side converter and the power grid, or on the connection line between at least one machine-side output port of the corresponding machine-side converter and the generator device.

[0015] Another aspect of the present invention is to provide a wind power converter device, comprising: a plurality of grid-side converters, a plurality of machine-side converters, and a DC bus module. The plurality of grid-side converters are arranged under the tower of the wind power system, and each includes a plurality of grid-side output ports electrically coupled to the power grid, a first DC input port, and a second DC input port, and the second DC input port of one of any two adjacent grid-side converters is connected in series with the first DC input port of the other; the plurality of machine-side converters are arranged on the tower of the wind power system, and each includes a machine-side input port electrically coupled to the generator device, a first DC output port, and a second DC output port, and the second DC output port of one of any two adjacent machine-side converters is connected in series with the first DC output port of the other. The DC bus module includes a plurality of DC buses, electrically coupled between the grid-side converters and the machine-side converters. And a plurality of machine-side control modules, which communicate with each other and respectively control the operation of the corresponding machine-side converters. Each machine-side control module is preset with a protection condition. When the operating conditions of the machine-side converter corresponding to the machine-side control module and / or the grid-side converter electrically coupled to the corresponding machine-side converter reach the protection condition, the machine-side control module stops outputting the three-phase voltage control signal to stop the operation of the corresponding machine-side converter.

[0016] Optionally, when any one of the machine-side control modules stops outputting the three-phase voltage control signal, the other normally operating machine-side control modules further drive the corresponding machine-side converters to jointly share the operation required by the machine-side converter that stops outputting the three-phase voltage control signal.

[0017] Optionally, the machine-side control module is further configured to receive and generate a three-phase voltage control signal to control the operation of the corresponding machine-side converter according to the three-phase input current amount of the machine-side input port of the corresponding machine-side converter and the second axial general given current component.

[0018] Optionally, each of the machine-side control modules includes: a current extraction unit for extracting the three-phase input current amount; a first conversion unit for converting the three-phase input current amount into a first axial current component and a second axial current component; a first calculation unit for calculating and generating a first axial difference according to the first axial current component and the first axial independent given current component; a second calculation unit for calculating and generating a second axial difference according to the second axial current component and the second axial general given current component; a first current control unit for generating a first axial voltage control signal according to the first axial difference; a second current control unit for generating a second axial voltage control signal according to the second axial difference; and a second conversion unit for converting the first axial voltage control signal and the second axial voltage control signal into a three-phase voltage control signal.

[0019] Optionally, the first conversion unit includes dq rotating coordinates of the d-axis and the q-axis, the first axial current component corresponds to the reactive current component on the d-axis, and the second axial current component corresponds to the active current component on the q-axis.

[0020] Optionally, in the wind power converter device described above, the number of the grid-side converter and the machine-side converter is both n, where n≥2; and the DC bus includes a positive DC bus, a negative DC bus, and at least one intermediate DC bus between the positive DC bus and the negative DC bus bracket; wherein the first DC input port of the first grid-side converter is electrically coupled to the first DC output port of the first machine-side converter through the positive DC bus; the second DC input port of the nth grid-side converter is electrically coupled to the second DC output port of the nth machine-side converter through the negative DC bus; and the second DC input ports of the (n - 1)th grid-side converter and the second DC output ports of the (n - 1)th machine-side converter are electrically coupled through the intermediate DC bus.

[0021] Optionally, in the wind power converter device described above, it further includes a plurality of machine-side control modules, and each of the machine-side control modules is configured to receive and generate a three-phase voltage control signal to control the operation of the corresponding machine-side converter according to the three-phase input current amounts of the machine-side input port corresponding to the machine-side converter and the second axial general given current component.

[0022] Optionally, each of the machine-side control modules includes: a current extraction unit configured to extract the three-phase input current amounts; a first conversion unit configured to convert the three-phase input current amounts into a first axial current component and a second axial current component; a first calculation unit configured to calculate and generate a first axial difference according to the first axial current component and the first axial independent given current component; a second calculation unit configured to calculate and generate a second axial difference according to the second axial current component and the second axial general given current component; a first current control unit configured to generate a first axial voltage control signal according to the first axial difference; a second current control unit configured to generate a second axial voltage control signal according to the second axial difference; and a second conversion unit configured to convert the first axial voltage control signal and the second axial voltage control signal into a three-phase voltage control signal.

[0023] Optionally, the first conversion unit includes dq rotating coordinates of the d-axis and the q-axis, the first axial current component corresponds to the reactive current component on the d-axis, and the second axial current component corresponds to the active current component on the q-axis.

[0024] Optionally, in the aforementioned wind power converter device, the DC bus module includes a plurality of first bus capacitor groups and a plurality of second bus capacitor groups, wherein the first bus capacitor groups correspond one-to-one to the grid-side converters, and each first bus capacitor group is connected in parallel between the first DC input port and the second DC input port of the corresponding grid-side converter; the second bus capacitor groups correspond one-to-one to the machine-side converters, and each second bus capacitor group is connected in parallel between the first DC output port and the second DC output port of the corresponding machine-side converter.

[0025] Optionally, in the aforementioned wind power converter device, the generator device includes multiple sets of windings, and each set of the multiple sets of windings is electrically coupled to the machine-side input port of the corresponding machine-side converter.

[0026] Optionally, the machine-side converter is a two-level converter, and the grid-side converter is a two-level converter; or the machine-side converter is a three-level converter, and the grid-side converter is a three-level converter.

[0027] Optionally, the wind power converter device further includes a plurality of chopper circuits, and the chopper circuits are connected in parallel between the first DC output port and the second DC output port of the machine-side converter.

[0028] Optionally, the machine-side control module includes a main machine-side control module and at least one slave machine-side control module, and the main machine-side control module outputs a second axial general given current component to at least one slave machine-side control module respectively.

[0029] Optionally, the machine-side control module includes a main machine-side control module and at least one slave machine-side control module, and the main machine-side control module generates and outputs a second axial general given current component to at least one slave machine-side control module respectively.

[0030] Optionally, the number of the grid-side converters is n and the number of the machine-side converters is 2n, and the grid-side converter further includes a first DC midpoint, where n≥1; and the DC bus includes a positive DC bus, a negative DC bus, and at least one intermediate DC bus between the positive DC bus and the negative DC bus; wherein, the first DC input end of the first grid-side converter is electrically coupled to the first DC output end of the first machine-side converter through the positive DC bus; the second DC input port of the nth grid-side converter is electrically coupled to the second DC output port of the 2nth machine-side converter through the negative DC bus; and between the first DC midpoint of the nth grid-side converter and the first DC output end of the 2nth machine-side converter, and between the second DC input port of the (n - 1)th grid-side converter and the first DC output end of the (2n - 1)th machine-side converter are electrically coupled through the intermediate DC bus.

[0031] Optionally, the number of grid-side converters is 2n and the number of machine-side converters is n, and the machine-side converter further includes a second DC midpoint, where n≥1; and the DC bus includes a positive DC bus, a negative DC bus, and at least one intermediate DC bus between the positive DC bus and the negative DC bus bracket; wherein, the first DC input end of the first grid-side converter is electrically coupled to the first DC output end of the first machine-side converter through the positive DC bus; the second DC input port of the 2nth grid-side converter is electrically coupled to the second DC output port of the nth machine-side converter through the negative DC bus; and between the first DC input port of the 2nth grid-side converter and the second DC midpoint of the nth machine-side converter, and between the first DC input port of the (2n - 1)th grid-side converter and the second DC output port of the nth machine-side converter are both electrically coupled through the intermediate DC bus.

[0032] The advantages of applying the present invention are that the wind power converter device can electrically couple the first DC input port and the second DC input port between any two adjacent grid-side converters to connect the DC sides of the grid-side converters in series, and electrically couple the first DC output port and the second DC output port between any two adjacent machine-side converters to connect the DC sides of the machine-side converters in series, and easily achieve the above object. In other wind power converter devices, among the multiple DC buses, there are a positive DC bus, a negative DC bus, and at least one intermediate DC bus between the positive DC bus and the negative DC bus. The cross-sectional area of the conductor of the intermediate DC bus can be less than 30% of the cross-sectional area of the conductor of the positive DC bus; or the cross-sectional area of the conductor of the intermediate DC bus can be less than 30% of the cross-sectional area of the conductor of the negative DC bus, so as to more easily achieve the above object. In other wind power converter devices, the positive DC bus, the negative DC bus, or the intermediate DC bus can include part or all of the copper bars or include part or all of the aluminum bars, and easily achieve the above object. In other wind power converter devices, multiple machine-side control modules can communicate with each other and each preset a protection condition. When the operating conditions of the machine-side converter corresponding to the machine-side control module and / or the grid-side converter electrically coupled to the corresponding machine-side converter reach the protection condition, the machine-side control module stops outputting the three-phase voltage control signal to stop the operation of the corresponding machine-side converter, and easily achieve the above object. In other wind power converter devices, the above object can be easily achieved through the setting of passive circuit protection elements. In other wind power converter devices, the above object can be easily achieved through the setting of active circuit protection elements and detection circuits. Description of the Drawings

[0033] Figure 1 It is a circuit diagram of a wind power converter device in the first embodiment of the present invention;

[0034] Figure 2In the second embodiment of the present invention, it is a circuit diagram of a wind power converter device;

[0035] Figure 3 In the third embodiment of the present invention, it is a circuit diagram of a wind power converter device:

[0036] Figure 4 In the fourth embodiment of the present invention, it is a circuit diagram of a wind power converter device:

[0037] Figure 5 In the fifth embodiment of the present invention, it is a circuit diagram of a wind power converter device:

[0038] Figure 6 In the sixth embodiment of the present invention, it is a circuit diagram of a wind power converter device:

[0039] Figure 7 In one embodiment of the present invention, it is a block diagram of a machine-side control module:

[0040] Figure 8 In the seventh embodiment of the present invention, it is a circuit diagram of a wind power converter device;

[0041] Figure 9 In the eighth embodiment of the present invention, it is a circuit diagram of a wind power converter device;

[0042] Figure 10 In the ninth embodiment of the present invention, it is a circuit diagram of a wind power converter device;

[0043] Figure 11 In the tenth embodiment of the present invention, it is a circuit diagram of a wind power converter device;

[0044] Figure 12 In the eleventh embodiment of the present invention, it is a circuit diagram of a wind power converter device.

[0045] Among them, the reference numerals are explained as follows:

[0046] 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11: Wind power converter device

[0047] 10A - 10C: Grid-side converter

[0048] 11A, 11B: Machine-side control module

[0049] 12A - 12C: Machine-side converter

[0050] 13A - 13C: Chopper circuit

[0051] 16: Power grid

[0052] 160: Transformer

[0053] 18: Generator device

[0054] 41A - 41C: Machine - side control module

[0055] 400, 402, 404, 406: DC bus

[0056] 500: Current extraction unit

[0057] 502: First conversion unit

[0058] 504: First calculation unit

[0059] 506: Second calculation unit

[0060] 508: First current control unit

[0061] 510: Second current control unit

[0062] 512: Second conversion unit

[0063] 6: Wind power converter device

[0064] 7: Wind power converter device

[0065] 8: Wind power converter device

[0066] 80A: Grid - side converter

[0067] 81A - 81B: Machine - side control module

[0068] 82A - 82B: Machine - side converter

[0069] 83A - 83B: Chopper circuit

[0070] 9: Wind power converter device

[0071] 90A - 90B: Grid - side converter

[0072] 92A: Machine - side converter

[0073] 93A - 93B: Chopper circuit

[0074] 10: Wind power converter device

[0075] 100A - 100B: Grid - side converter

[0076] 101A - 101D: Machine - side control module

[0077] 102A - 102D: Machine - side converter

[0078] 103A - 103D: Chopper circuit

[0079] 1000 - 1004: DC bus

[0080] 110A - 110D: Grid - side converter

[0081] 1100 - 1104: DC bus

[0082] 11: Wind power converter device

[0083] 110A - 110D: Grid - side converter

[0084] 111A - 111B: Machine - side control module

[0085] 112A - 112B: Machine - side converter

[0086] 113A - 113D: Chopper circuit

[0087] 17A - 17D, 17E, 17F: Passive circuit protection components

[0088] 17G - 17J: Active circuit protection components

[0089] 19A - 19D, 19E, 19F: Detection circuit Detailed implementation manner

[0090] Please refer to Figure 1 . Figure 1 In the first embodiment of the present invention, it is a circuit diagram of a wind power converter device 1. The wind power converter device 1 includes: grid - side converters 10A - 10C, machine - side converters 12A - 12C, and a DC bus module. The grid - side converters and the machine - side converters are respectively arranged in the lower part and the upper part of the tower of the wind power system. Among them, the machine - side converters 12A - 12C are arranged in the nacelle at the top of the tower of the wind power system, and the grid - side converters 10A - 10C are arranged at the bottom of the tower or outside the tower, which can reduce the cable cost required for transmitting signals between the upper part and the lower part of the tower, and can also balance the load - bearing capacity on the tower.

[0091] In one embodiment, a plurality of grid-side converters are disposed under a tower of a wind power system, and each includes a plurality of grid-side output ports electrically coupled to a power grid, a first DC input port, and a second DC input port, and the second DC input port of one of any two adjacent grid-side converters is connected in series with the first DC input port of the other; a plurality of machine-side converters are disposed on the tower of the wind power system, and each includes a machine-side input port electrically coupled to a generator device, a first DC output port, and a second DC output port, and the second DC output port of one of any two adjacent machine-side converters is connected in series with the first DC output port of the other, and a DC bus module includes a plurality of DC buses electrically coupled between the grid-side converters and the machine-side converters; wherein at least one of the DC buses includes part or all of copper bars or includes part or all of aluminum bars.

[0092] The number of the grid-side converters and the machine-side converters is both n, n≥2; and the DC bus includes a positive DC bus, a negative DC bus, and at least one intermediate DC bus between the positive DC bus and the negative DC bus; wherein the first DC input port of the first grid-side converter is electrically coupled to the first DC output port of the first machine-side converter through the positive DC bus; the second DC input port of the nth grid-side converter is electrically coupled to the second DC output port of the nth machine-side converter through the negative DC bus; and the second DC input port of the (n-1)th grid-side converter and the second DC output port of the (n-1)th machine-side converter are both electrically coupled through the intermediate DC bus.

[0093] In one embodiment, the grid-side converters 10A-10C may include the same components. Taking the grid-side converter 10A as an example, in this embodiment, the grid-side converter is a two-level converter and has a plurality of grid-side output ports (such as 3 grid-side output ports) N1-N3 electrically coupled to the power grid 16, a first DC input port IN1, and a second DC input port IN2. In one embodiment, the grid-side output ports N1-N3 are electrically coupled to the power grid 16 through a transformer 160.

[0094] The first DC input port IN1 of one of any two adjacent grid-side converters among the grid-side converters 10A-10C is connected in series with the second DC input port IN2 of the other. Taking the grid-side converters 10A, 10B, and 10C as an example, the second DC input port IN2 of the grid-side converter 10A is connected in series with the first DC input port IN1 of the grid-side converter 10B, and the second DC input port IN2 of the grid-side converter 10B is connected in series with the first DC input port IN1 of the grid-side converter 10C.

[0095] In one embodiment, the number of machine-side converters 12A-12C is equal to the number of grid-side converters 10A-10C, and the machine-side converters 12A-12C may include the same components. Taking the machine-side converter 12A as an example, in this embodiment, the machine-side converter is a two-level converter and has a machine-side input port (such as 3 machine-side input terminals) O1-O3 electrically coupled to the generator device 18, a first DC output port OUT1, and a second DC output port OUT2. In one embodiment, the generator device 18 is a permanent magnet synchronous generator device, an electrically excited synchronous generator device, or an induction generator device with multiple sets of windings, and the generator device 18 includes multiple sets of windings, where each set of windings corresponds to a machine-side converter, and each set of windings includes 3 windings (not shown in the figure). The 3 windings of each set of windings are electrically coupled to multiple machine-side input terminals O1-O3 of the corresponding machine-side converter. Taking the machine-side converter 12A as an example, in this embodiment, the 3 windings of a set of windings in the generator device 18 are respectively electrically coupled to the 3 machine-side input terminals O1-O3 of the corresponding machine-side converter 12A. In one embodiment, the machine-side converter can be coupled to the generator device through a filtering circuit such as an inductor or a capacitor (not shown in the figure).

[0096] Any two adjacent machine-side converters among the machine-side converters 12A-12C are connected in series through the first DC output port OUT1 and the second DC output port OUT2. Taking the machine-side converters 12A, 12B, and 12C as an example, the second DC output port OUT2 of the machine-side converter 12A is connected in series with the first DC output port OUT1 of the machine-side converter 12B, and the second DC output port OUT2 of the machine-side converter 12B is connected in series with the first DC output port OUT1 of the machine-side converter 12C.

[0097] The DC bus module includes DC buses 400, 402, 404, and 406. Among them, DC bus 400 is electrically coupled to the first DC input port IN1 of the grid-side converter 10A and the first DC output port OUT1 of the machine-side converter 12A. This DC bus 400 is a positive DC bus for conducting positive direct current. DC bus 402 is electrically coupled to the second DC input port IN2 of the grid-side converter 10A and the second DC output port OUT2 of the machine-side converter 12A (equivalent to the first DC input port IN1 of the grid-side converter 10B and the first DC output port OUT1 of the machine-side converter 12B). DC bus 404 is electrically coupled to the second DC input port IN2 of the grid-side converter 10B and the second DC output port OUT2 of the machine-side converter 12B (equivalent to the first DC input port IN1 of the grid-side converter 10C and the first DC output port OUT1 of the machine-side converter 12C). These DC buses 402 and 404 are intermediate DC buses. DC bus 406 is electrically coupled to the second DC input port IN2 of the grid-side converter 10C and the second DC output port OUT2 of the machine-side converter 12C. This DC bus 406 is a negative DC bus for conducting negative direct current. Among them, the cross-sectional area of the intermediate DC bus conductor can be less than 30% of the cross-sectional area of the positive DC bus conductor; or the cross-sectional area of the intermediate DC bus conductor can be less than 30% of the cross-sectional area of the negative DC bus conductor.

[0098] In one embodiment, the DC bus module further includes bus capacitor groups C1 - C6, which are respectively connected in parallel between the first DC input port IN1 and the second DC input port IN2 of each grid-side converter 10A - 10C, and between the first DC output port OUT1 and the second DC output port OUT2 of each machine-side converter 12A - 12C to provide voltage support for these ports. Among them, the bus capacitor groups C1 - C6 include one capacitor element or multiple capacitor elements connected in series with each other.

[0099] In one embodiment, the wind power converter device 1 further includes chopper circuits 13A, 13B, and 13C. The chopper circuits 13A - 13C are respectively connected in parallel between the first DC output port OUT1 and the second DC output port OUT2 of the machine - side converters 12A - 12C for voltage equalization protection of the machine - side converters 12A - 12C. Taking the chopper circuit 13A as an example, the chopper circuit 13A includes a controllable power semiconductor switch, a resistor, and two diodes. The collector of the controllable power semiconductor switch is connected to the cathode of a diode and the first DC output port OUT1 of the machine - side converter 12A, and the emitter of the controllable power semiconductor switch is electrically connected to the anode of the diode. One end of the resistor is connected to the emitter of the controllable power semiconductor switch, and the other end of the resistor is connected to the second DC output port OUT2 of the machine - side converter 12A, and the other diode is connected in parallel across the two ends of the resistor. In other embodiments, the wind power converter device 1 further includes chopper circuits respectively connected in parallel between the first DC input port and the second DC input port of each grid - side converter, and between the first DC output port and the second DC output port of each machine - side converter for voltage equalization protection of the machine - side converters and grid - side converters.

[0100] Therefore, the wind power converter device 1 of the present invention can connect the grid - side converters 10A - 10C in series by electrically coupling the first DC input port IN1 and the second DC input port IN2 between any two adjacent grid - side converters 10A - 10C, and connect the machine - side converters 12A - 12C in series by electrically coupling the first DC output port OUT1 and the second DC output port OUT2 between any two adjacent machine - side converters 12A - 12C.

[0101] Furthermore, by adopting the structure of series - coupling of the machine - side converters and series - coupling of the grid - side converters, the magnitude of the DC voltage between the positive DC bus and the negative DC bus can be adjusted by the number of series - connected grid - side converters and machine - side converters, making the design of the wind power converter device 1 more flexible. And the cross - sectional area of the intermediate DC bus conductor is less than 30% of the cross - sectional area of the positive DC bus conductor, and the cross - sectional area of the intermediate DC bus conductor is less than 30% of the cross - sectional area of the negative DC bus conductor. In this embodiment, the cross - sectional areas of the positive DC bus conductor and the negative DC bus conductor are the same, thus greatly reducing the cost of the DC bus between the grid - side converters 10A - 10C and the machine - side converters 12A - 12C.

[0102] In addition, in some embodiments, at least one of the DC buses 400, 402, 404, and 406 connecting the machine-side converters 12A-12C on the tower of the wind power system to the grid-side converters 10A-10C under the tower may include part or all of the copper bars or include part or all of the aluminum bars. For example, the DC bus 400 includes copper bars or aluminum bars, and the other DC buses 402, 404, and 406 are cables; or the DC buses 400, 402, 404, and 406 all include copper bars or aluminum bars, thereby further reducing the cost of the DC buses.

[0103] The control method of the machine-side converters 12A-12C will be described in more detail below.

[0104] The wind power converter device 1 further includes a plurality of machine-side control modules, which are in one-to-one correspondence with the machine-side converters. The machine-side control modules are used to receive and generate a three-phase voltage control signal to control the operation of the corresponding machine-side converter according to a three-phase input current amount and a second axial general given current component at the machine-side input port of the corresponding machine-side converter.

[0105] In this embodiment, the wind power converter device 1 further includes machine-side control modules 41A-41C. The machine-side control module 41A is used to control the machine-side converter 12A, the machine-side control module 41B is used to control the machine-side converter 12B, and the machine-side control module 41C is used to control the machine-side converter 12C. The machine-side control modules 41A-41C are used to generate three-phase voltage control signals V1-V3 to control the operation of the corresponding machine-side converters 12A-12C according to the three-phase input current amounts I1-I3 and the second axial general given current component i q_norm* at the machine-side input ports O1-O3 of the corresponding machine-side converters 12A-12C. In one embodiment, the machine-side control module includes a main machine-side control module and at least one slave machine-side control module. In one embodiment, the machine-side control modules 41A-41C may have the same architecture. Select one of the machine-side control modules to be defined as the main machine-side control module, and the others are defined as slave machine-side control modules. The following will take the machine-side control module 41A defined as the main machine-side control module as an example for description.

[0106] Please refer to Figure 7 . Figure 7 In an embodiment of the present invention, it is a block diagram of the machine-side control module 41A. The machine-side control module 41A includes: a current extraction unit 500, a first conversion unit 502, a first calculation unit 504, a second calculation unit 506, a first current control unit 508, a second current control unit 510, and a second conversion unit 512.

[0107] The current extraction unit 500 is electrically coupled to the machine-side input ports O1 - O3 of the machine-side converter 12A to extract the three-phase input current amount I1. In one embodiment, the three-phase input current amount I1 includes three components i a_i , i b_i , and i c_i .

[0108] The first conversion unit 502 converts the three components i a_i , i b_i , and i c_i of the three-phase input current amount I1 into a first axial current component i d_i and a second axial current component i q_i . In one embodiment, the first conversion unit 502 includes a dq rotating coordinate of the d-axis and the q-axis, and the first axial current component i d_i and the second axial current component i q_i are respectively located on the d-axis and the q-axis of the dq rotating coordinate. In one embodiment, the first axial current component i d_i is a reactive current component, and the second axial current component i q_i is an active current component. In other embodiments, the first axial current component i d_i can be an active current component, and the second axial current component i q_i can be a reactive current component.

[0109] The first calculation unit 504 calculates and generates a first axial difference i d_i based on the first axial current component i d_i* and the first axial independent given current component i d_id .

[0110] The second calculation unit 506 calculates a second axial difference i q_i based on the second axial current component i q_norm* and the second axial general given current component i q_id . In this embodiment, the second axial general given current component i q_norm* is generated by the host-side control module 41A, and then the host-side control module 41A outputs the second axial general given current component i q_norm* to the slave-side control modules 41B - 41C respectively. In other embodiments, the second axial general given current component i q_norm* is generated by a main control machine (not shown in the figure) and output to the host-side control module 41A, and then the host-side control module 41A outputs the second axial general given current component i q_norm*They are respectively output to the slave - side control modules 41B - 41C. In this embodiment, the machine - side control module 41A communicates with the machine - side control modules 41B and 41C. In other embodiments, the machine - side control module 41B or 41C can also be used as the host - side control module to receive the second axial general given current component i from the master controller. q_norm* And transmit it to other machine - side control modules.

[0111] The first current control unit 508 generates a first axial voltage control signal V according to the first axial difference i d_id d_i . The second current control unit 510 generates a second axial voltage control signal V according to the second axial difference i q_id q_i . The second conversion unit 512 further converts the first axial voltage control signal V d_i and the second axial voltage control signal V q_i into a three - phase voltage control signal V1. In one embodiment, the three - phase voltage control signal V1 includes three components V a_i , V b_i and V c_i .

[0112] Therefore, by controlling the power semiconductor switch elements in the corresponding machine - side converter 12A through the three - phase voltage control signal V1, the machine - side converter operates, such as in the rectification state, the inversion state, or the shutdown state. Therefore, the wind power converter device 1 of the present invention can effectively control the machine - side converters 12A - 12C through the machine - side control modules 41A - 41C in the above - mentioned manner.

[0113] In this embodiment, in addition to the machine-side control modules 41A, 41B, and 41C being able to communicate with each other, each of the machine-side control modules 41A, 41B, and 41C is preset with a protection condition. When the operating conditions of the machine-side converter 12A corresponding to the machine-side control module 41A and / or the grid-side converter 10A electrically coupled to the corresponding machine-side converter 12A reach the protection condition, for example, a DC fault is detected on the coupling path between the grid-side converter 10A and the power grid 16, or a DC fault on the DC buses 400 and 402, or a DC fault on the coupling path between the machine-side converter 12A and the generator device 18, the machine-side control module 41A stops outputting the three-phase voltage control signal V1 to stop the corresponding machine-side converter 12A from operating. Similarly, when the operating conditions of the machine-side converter 12B corresponding to the machine-side control module 41B and / or the grid-side converter 10B electrically coupled to the corresponding machine-side converter 12B reach the protection condition, the machine-side control module 41B stops outputting the three-phase voltage control signal V2 to stop the corresponding machine-side converter 12B from operating. When the operating conditions of the machine-side converter 12C corresponding to the machine-side control module 41C and / or the grid-side converter 10C electrically coupled to the corresponding machine-side converter 12C reach the protection condition, the machine-side control module 41C stops outputting the three-phase voltage control signal V3 to stop the corresponding machine-side converter 12C from operating. In addition, since the machine-side control modules 41A, 41B, and 41C can communicate with each other, when any one of the machine-side control modules stops operating, the other normally operating machine-side control modules can drive the corresponding machine-side converters to jointly share the operation required by the stopped machine-side converter. In this way, the wind power converter device 1 has a redundant operation function, and when any converter fails, the other normally operating converters can jointly share the operation required by the failed converter, so the stability and reliability of the wind power generation device 1 can be improved. Among them, in other embodiments, the protection condition can be set to the occurrence of overcurrent and / or overvoltage and other situations.

[0114] In order to improve the reliability of the wind power converter device, in some embodiments, the wind power converter device may further include at least one passive circuit protection element, which is disposed in at least one power transmission path established by the corresponding grid-side converter, the corresponding machine-side converter, and the DC bus module and located between the power grid 16 and the generator device 18. Electric power is transmitted between the power grid and the generator device through the power transmission path, and the passive circuit protection element has a preset current value. When the current on the power transmission path corresponding to the passive circuit protection element exceeds the preset current value of the passive circuit protection element, the passive circuit protection element is in an open circuit state, thereby protecting the components in the grid-side converter and the machine-side converter existing on the corresponding power transmission path from overcurrent, thereby improving the reliability of the wind power converter device. The passive circuit protection element may be a fuse or the like. The following will use Figures 1-3 to further illustrate the possible implementation manners of different installation positions of the passive circuit protection element. As Figure 1 shown, the wind power converter device 1 may include at least one passive circuit protection element, such as four passive circuit protection elements 17A, 17B, 17C, 17D. The passive circuit protection element 17A is disposed on the DC bus 400 and is electrically coupled to the first DC input port IN1 of the grid-side converter 10A and the first DC output port OUT1 of the machine-side converter 12A. The passive circuit protection element 17B is disposed on the DC bus 402 and is electrically coupled to the second DC input port IN2 of the grid-side converter 10A and the second DC output port OUT2 of the machine-side converter 12A. The passive circuit protection element 17C is disposed on the DC bus 404 and is electrically coupled to the second DC input port IN2 of the grid-side converter 10B and the second DC output port OUT2 of the machine-side converter 12B. The passive circuit protection element 17D is disposed on the DC bus 406 and is electrically coupled to the second DC input port IN2 of the grid-side converter 10C and the second DC output port OUT2 of the machine-side converter 12C.

[0115] Please refer to Figure 2 . Figure 2 This is the circuit diagram of a wind power converter device in the second embodiment of the present invention. The wind power converter device 2 may include at least one passive circuit protection element, such as a plurality of passive circuit protection elements 17E. Each passive circuit protection element 17E is respectively disposed on the connection line between at least one grid-side output port (such as 3 grid-side output ports N1-N3) of the grid-side converters 10A-10C and the power grid 16. For example, passive protection elements 17E are disposed on the connection lines between the 3 grid-side output ports N1-N3 and the power grid 16; or passive protection elements 17E are disposed on the connection line between one or both of the 3 grid-side output ports N1-N3 and the power grid 16. Please refer to Figure 3 . Figure 3In the third embodiment of the present invention, it is a circuit diagram of a wind power converter device. The wind power converter device 3 may include at least one passive circuit protection element, such as a plurality of passive circuit protection elements 17F, where each passive circuit protection element 17F is respectively arranged on the connection line between the machine-side input ports (such as 3 machine-side input terminals O1 - O3) of the machine-side converters 12A - 12C and the generator device 18. For example, passive circuit protection elements 17F are arranged on the connection lines between the 3 machine-side input terminals O1 - O3 and the generator device 18; or passive circuit protection elements 17F are arranged on the connection lines between one or both of the 3 machine-side input terminals O1 - O3 and the generator device 18.

[0116] In one embodiment, the protection conditions of the machine-side control module 41A, the machine-side control module 41B, and the machine-side control module 41C can be set to the situation where the corresponding passive circuit protection element switches to an open circuit state.

[0117] Of course, in other embodiments, Figures 1 to 3 The passive circuit protection elements in the shown wind power converter device can be changed to active circuit protection elements, such as relays or switch elements, etc. Correspondingly, the wind power converter device needs to further include at least one detection circuit. The number of detection circuits corresponds to the number of active circuit protection elements, and each detection circuit and the corresponding active circuit protection element are also arranged in the power transmission path established by the corresponding grid-side converter, the corresponding machine-side converter, and the DC bus module and located between the power grid and the generator device. Each detection circuit is used to detect whether there is an abnormality in the electric energy on the corresponding power transmission path, such as a DC fault, and when an abnormality is detected, it outputs a corresponding abnormality signal, and the corresponding active circuit protection element switches to an open circuit state according to the abnormality signal. The detection circuit can be a current sensor, etc. The following will Figures 4-6 Further illustrate the possible implementation manners of different installation positions of the detection circuit. Since the installation position of the active circuit protection element can be similar to Figures 1 to 3 the passive circuit protection elements in the shown wind power converter device, Figures 4-6 only one installation position of the active circuit protection element is exemplified. Please refer to Figure 4 . [[ID=...]] Figure 4In the fourth embodiment of the present invention, it is a circuit diagram of a wind power converter device. The wind power converter device 4 may include at least one active circuit protection element and at least one detection circuit, such as four active circuit protection elements 17G, 17H, 17I, 17J and four detection circuits 19A, 19B, 19C, 19D. The active circuit protection element 17G is disposed on the DC bus 400 and is electrically coupled to the first DC input port IN1 of the grid-side converter 10A and the first DC output port OUT1 of the machine-side converter 12A. The active circuit protection element 17H is disposed on the DC bus 402 and is electrically coupled to the second DC input port IN2 of the grid-side converter 10A and the second DC output port OUT2 of the machine-side converter 12A (equivalent to being electrically coupled to the first DC input port IN1 of the grid-side converter 10B and the first DC output port OUT1 of the machine-side converter 12B). The active circuit protection element 17I is disposed on the DC bus 404 and is electrically coupled to the second DC input port IN2 of the grid-side converter 10B and the second DC output port OUT2 of the machine-side converter 12B (equivalent to being electrically coupled to the first DC input port IN1 of the grid-side converter 10C and the first DC output port OUT1 of the machine-side converter 12C). The active circuit protection element 17J is disposed on the DC bus 406 and is electrically coupled to the second DC input port IN2 of the grid-side converter 10C and the second DC output port OUT2 of the machine-side converter 12C. The detection circuit 19A is also disposed on the DC bus 400. The detection circuit 19A is used to detect whether the electric energy on the DC bus 400 of the corresponding power transmission path is abnormal, and when an abnormality is detected, it outputs a corresponding abnormal signal, and the corresponding active circuit protection element 17G switches to an open state according to the abnormal signal output by the detection circuit 19A. The detection circuit 19B is also disposed on the DC bus 402. The detection circuit 19B is used to detect whether the electric energy on the DC bus 402 of the corresponding power transmission path is abnormal, and when an abnormality is detected, it outputs a corresponding abnormal signal, and the corresponding active circuit protection element 17H switches to an open state according to the abnormal signal output by the detection circuit 19B. The detection circuit 19C is also disposed on the DC bus 404. The detection circuit 19C is used to detect whether the electric energy on the DC bus 404 of the corresponding power transmission path is abnormal, and when an abnormality is detected, it outputs a corresponding abnormal signal, and the corresponding active circuit protection element 17I switches to an open state according to the abnormal signal output by the detection circuit 19C. The detection circuit 19D is also disposed on the DC bus 406. The detection circuit 19D is used to detect whether the electric energy on the DC bus 406 of the corresponding power transmission path is abnormal, and when an abnormality is detected, it outputs a corresponding abnormal signal, and the corresponding active circuit protection element 17J switches to an open state according to the abnormal signal output by the detection circuit 19D.In other embodiments, the number of detection circuits may not correspond to the number of active circuit protection elements. For example, one detection circuit corresponds to multiple active circuit protection elements. The detection circuit is disposed in the power transmission path established by the corresponding grid-side converter, the corresponding machine-side converter, and the DC bus module and located between the power grid and the generator device. The detection circuit is used to detect whether there is an abnormality in the power on the corresponding power transmission path, and when an abnormality is detected, output a corresponding abnormality signal, and the active circuit protection element switches to an open state according to the abnormality signal.

[0118] Please refer to Figure 5 。 Figure 5 FIG. is a circuit diagram of a wind power converter device according to a fifth embodiment of the present invention. The wind power converter device 5 may include at least one detection circuit, such as a plurality of detection circuits 19E. Each detection circuit 19E is respectively disposed on the connection line between at least one grid-side output port (such as 3 grid-side output ports N1-N3) of the grid-side converters 10A-10C and the power grid 16. Detection circuits 19E are provided on the connection lines with the power grid 16, such as on the connection lines between 3 grid-side output ports N1-N3 and the power grid 16, or detection circuits 19E are provided on the connection lines of one or both of the 3 grid-side output ports N1-N3 with the power grid 16. Each detection circuit 19E is used to detect whether there is an abnormality in the power on the grid-side output port of the corresponding power transmission path, and when an abnormality is detected, output a corresponding abnormality signal, and the corresponding active circuit protection element switches to an open state according to the abnormality signal output by the corresponding detection circuit. Please refer to Figure 6 。 Figure 6 FIG. is a circuit diagram of a wind power converter device according to a sixth embodiment of the present invention. The wind power converter device 6 may include at least one detection circuit, such as a plurality of detection circuits 19F. Each detection circuit 19F is respectively disposed on the connection line between the machine-side input ports (such as 3 machine-side input terminals O1-O3) of the machine-side converters 12A-12C and the generator device 18. Detection circuits 19F are provided on the connection lines between 3 machine-side input terminals O1-O3 and the generator device 18, or detection circuits 19F are provided on the connection lines of one or both of the 3 machine-side input terminals O1-O3 with the generator device 18. Each detection circuit 19F is used to detect whether there is an abnormality in the power on the grid-side output port of the corresponding power transmission path, and when an abnormality is detected, output a corresponding abnormality signal, and the corresponding active circuit protection element switches to an open state according to the abnormality signal output by the corresponding detection circuit.

[0119] In one embodiment, the protection conditions of the machine-side control module 41A, the machine-side control module 41B, and the machine-side control module 41C may be set to the occurrence of receiving the abnormality signal output by the corresponding detection circuit.

[0120] The following will further illustrate the possible implementation manners of different numbers of the grid-side converter and the machine-side converter, as well as the possible implementation manners of different architectures of the grid-side converter and the machine-side converter. Among the multiple technical features disclosed above, for example, the cross-sectional area of the intermediate DC bus conductor is less than 30% of the cross-sectional area of the positive DC bus conductor, or the cross-sectional area of the intermediate DC bus conductor is less than 30% of the cross-sectional area of the negative DC bus conductor, at least one DC bus may include part or all of the copper bars, or include part or all of the aluminum bars, the redundant operation function of the wind power converter device 1, the setting and application of passive circuit protection components, the setting and application of active circuit protection components and detection circuits, etc. can all be applied to at least one of the following drawings. Therefore, the following drawings or descriptions do not show or elaborate on the aforementioned technical features.

[0121] Please refer to Figure 8 。 Figure 8 This is the circuit diagram of a wind power converter device 7 in the seventh embodiment of the present invention. The wind power converter device 7 includes: grid-side converters 10A - 10B, machine-side converters 12A - 12B, and a DC bus module. Similar to Figure 1 the wind power converter device 1 shown, the grid-side converters 10A - 10B of the wind power converter device 7 are connected in series with each other, and the machine-side converters 12A - 12B are also connected in series with each other. Most of the components included in the wind power converter device 7 are Figure 1 the same as those of the wind power converter device 1, except that the numbers of the grid-side converters 10A - 10B and the machine-side converters 12A - 12B are two.

[0122] It should be noted that except for Figure 1 and Figure 8 the exceptions where the grid-side converters 10A - 10B and the machine-side converters 12A - 12B shown are three and two respectively, in other embodiments, the wind power converter device may also include more numbers of grid-side converters and machine-side converters, and can achieve efficient control through the above-mentioned mechanism.

[0123] Of course, in other embodiments, the grid-side converters and the machine-side converters of the wind power converter device may also be three-level converters respectively. Similarly, the three-level architecture can also be applied to Figure 1 the wind power converter device 1.

[0124] Please refer to Figure 9 。 Figure 9 This is the circuit diagram of a wind power converter device 8 in the eighth embodiment of the present invention.

[0125] The wind power converter device 8 includes a grid-side converter 80A, a machine-side converter 82A - 82B, and a DC bus module. Among them, the machine-side converters 82A - 82B included in the wind power converter device 8 are connected in series with each other. However, the grid-side converter 80A of the wind power converter device 8 is a three-level converter, while the machine-side converter is a two-level converter. The second DC output port OUT2 of the machine-side converter 82A is connected in series with the first DC output port OUT1 of the machine-side converter 82B. In this embodiment, the DC bus module includes three DC buses 800, 801, and 802. Among them, the DC bus 800 is electrically coupled between the first DC input port IN1 of the grid-side converter 80A and the first DC output port OUT1 of the machine-side converter 82A. This DC bus 800 is a positive DC bus for conducting positive direct current. The DC bus 801 is electrically coupled between the first DC midpoint IN0 of the grid-side converter 80A and the second DC output port OUT2 of the machine-side converter 82A and the first DC output port OUT1 of the machine-side converter 82B. This DC bus 801 is an intermediate DC bus. The DC bus 802 is electrically coupled between the second DC input port IN2 of the grid-side converter 80A and the second DC output port OUT2 of the machine-side converter 82B. This DC bus 802 is a negative DC bus for conducting negative direct current. In this embodiment, the machine-side control modules 81A and 81B can then adopt the aforesaid Figure 7 mechanism to control the machine-side converters 82A and 82B.

[0126] In one embodiment, the DC bus module further includes bus capacitor groups C1 - C4, which are respectively electrically coupled between the first DC input port IN1 and the first DC midpoint IN0 of the grid-side converter 80A, between the first DC midpoint IN0 and the second DC input port IN2 of the grid-side converter, and between the first DC output port OUT1 and the second DC output port OUT2 of the machine-side converters 82A and 82B to provide voltage support for the ports.

[0127] In one embodiment, the wind power converter device 1 further includes chopper circuits 83A and 83B. The chopper circuits 83A and 83B are respectively connected in parallel between the first DC output port OUT1 and the second DC output port OUT2 of the machine-side converter 82A and between the first DC output port OUT1 and the second DC output port OUT2 of the machine-side converter 82B to perform voltage equalization protection on the machine-side converters 82A and 82B.

[0128] Similarly, this asymmetric architecture can also be applied to Figure 1 the wind power converter device 1.

[0129] Please refer to Figure 10 . Figure 10In the ninth embodiment of the present invention, it is a circuit diagram of a wind power converter device 9.

[0130] The wind power converter device 9 includes grid-side converters 90A - 90B, a machine-side converter 92A, and a DC bus module. Among them, the grid-side converters 90A - 90B included in the wind power converter device 9 are connected in series with each other. However, the machine-side converter 92A of the wind power converter device 9 is a three-level converter, and the grid-side converters 90A - 90B are two-level converters. In this embodiment, the DC bus module includes DC buses 900, 901, and 902. Among them, the DC bus 900 is electrically coupled between the first DC input port IN1 of the grid-side converter 90A and the first DC output port OUT1 of the machine-side converter 92A, and this DC bus 900 is the positive DC bus. The DC bus 901 is electrically coupled between the second DC input port IN2 of the grid-side converter 90A, the first DC input port IN1 of the grid-side converter 90B, and the second DC midpoint OUT0 of the machine-side converter 92A, and this DC bus 901 is the intermediate DC bus. The DC bus 902 is electrically coupled between the second DC input port IN2 of the grid-side converter 90B and the second DC output port OUT2 of the machine-side converter 92A, and this DC bus 902 is the negative DC bus.

[0131] In an embodiment, the DC bus module further includes bus capacitor groups C1 - C4, which are respectively electrically coupled between the first DC input port IN1 and the second DC input port IN2 of the grid-side converter 90A, between the first DC input port IN1 and the second DC input port IN2 of the grid-side converter 90B, and between the first DC output port OUT1, the second DC midpoint OUT0, and the second DC output port OUT2 of the machine-side converter 92A to provide voltage support for the said ports.

[0132] In an embodiment, the wind power converter device 9 further includes chopper circuits 93A and 93B. The chopper circuits 93A and 93B are respectively connected in parallel between the first DC output port OUT1 and the second DC midpoint OUT0 of the machine-side converter 92A and between the second DC midpoint OUT0 and the second DC output port OUT2 of the machine-side converter 9,2A to perform equalizing protection on the machine-side converter 92A.

[0133] Similarly, this asymmetric architecture can also be applied to Figure 1 the wind power converter device 1.

[0134] In one embodiment, the number of grid-side converters is n and the number of machine-side converters is 2n, and the grid-side converter further includes a first DC midpoint, where n≥1; and the DC bus includes a positive DC bus, a negative DC bus, and at least one intermediate DC bus between the positive DC bus and the negative DC bus bracket; wherein, the first DC input terminal of the first grid-side converter is electrically coupled to the first DC output terminal of the first machine-side converter through the positive DC bus; the second DC input port of the nth grid-side converter is electrically coupled to the second DC output port of the 2nth machine-side converter through the negative DC bus; and between the first DC midpoint of the nth grid-side converter and the first DC output port of the 2nth machine-side converter, the second DC input port of the (n - 1)th grid-side converter and the first DC output port of the (2n - 1)th machine-side converter are electrically coupled through the intermediate DC bus.

[0135] Figure 11 In the tenth embodiment of the present invention, it is a circuit diagram of a wind power converter device 10. The wind power converter device 10 includes: grid-side converters 100A-100B, machine-side converters 102A-102D, and a DC bus module. In one embodiment, the grid-side converters 100A-100B can be three-level converters and include the same components. The grid-side converters are electrically coupled to the power grid 16, and the grid-side converters 100A-100B are connected in series. The second DC input port IN2 of the grid-side converter 100A is connected in series with the first DC input port IN1 of the grid-side converter 100B.

[0136] In one embodiment, the machine-side converters 102A-102D may include the same components and can be two-level converters. The machine-side converters are electrically coupled to the generator device 18. Any two adjacent machine-side converters among the machine-side converters 102A-102D are connected in series through the first DC output port OUT1 and the second DC output port OUT2.

[0137] Taking the machine-side converters 102A and 102B as an example, the second DC output port OUT2 of the machine-side converter 102A is connected in series with the first DC output port OUT1 of the machine-side converter 102B. Similarly, the second DC output port OUT2 of the machine-side converter 102B is connected in series with the first DC output port OUT1 of the machine-side converter 102C. Similarly, the second DC output port OUT2 of the machine-side converter 102C is connected in series with the first DC output port OUT1 of the machine-side converter 102D.

[0138] The DC bus module includes DC buses 1000 - 1004. Among them, DC bus 1000 is electrically coupled between the first DC input port IN1 of the grid - side converter 100A and the first DC output port OUT1 of the machine - side converter 102A, and this DC bus 1000 is the positive DC bus. DC bus 1002 is electrically coupled between the second DC input port IN2 of the grid - side converter 100B and the second DC output port OUT2 of the machine - side converter 102D, and this DC bus 1002 is the negative DC bus. DC bus 1001 is electrically coupled between the first DC mid - point IN0 of the grid - side converter 100A and the first DC output port OUT1 of the machine - side converter 102B. DC bus 1003 is electrically coupled between the second DC input port IN2 of the grid - side converter 100A and the second DC output port OUT2 of the machine - side converter 102B, and DC bus 1004 is electrically coupled between the first DC mid - point IN0 of the grid - side converter 100B and the first DC output port OUT1 of the machine - side converter 102D. Among them, DC buses 1001, 1003, and 1004 are intermediate DC buses.

[0139] Therefore, the machine - side control modules 101A - 101D included in the wind power converter device 10 can adopt Figure 7 the mechanism to control the machine - side converters 102A - 102D.

[0140] In one embodiment, the DC bus module further includes bus capacitor groups C1 - C8, which are respectively electrically connected between the first DC input port IN1 and the first DC mid - point IN0 of the grid - side converters 100A - 100B, between the first DC mid - point IN0 and the second DC input port IN2, and between the first DC output port OUT1 and the second DC output port OUT2 of each machine - side converter 102A - 102D to provide voltage support for these ports.

[0141] In one embodiment, the wind power converter device 10 further includes chopper circuits 103A to 103D, which are respectively connected in parallel between the first DC output port OUT1 and the second DC output port OUT2 of the machine - side converters 102A to 102D for equal - voltage protection of the machine - side converters 102A, 102B, 102C, and 102D.

[0142] In one embodiment, the number of grid-side converters is 2n and the number of machine-side converters is n, and the machine-side converter further includes a second DC midpoint, where n≥1; and the DC bus includes a positive DC bus, a negative DC bus, and at least one intermediate DC bus between the positive DC bus and the negative DC bus bracket; wherein, the first DC input terminal of the first grid-side converter is electrically coupled to the first DC output terminal of the first machine-side converter through the positive DC bus; the second DC input port of the 2nth grid-side converter is electrically coupled to the second DC output port of the nth machine-side converter through the negative DC bus; and between the first DC input port of the 2nth grid-side converter and the second DC midpoint of the nth machine-side converter, and between the first DC input port of the (2n-1)th grid-side converter and the second DC output port of the nth machine-side converter are both electrically coupled through the intermediate DC bus.

[0143] Figure 12 In the eleventh embodiment of the present invention, it is a circuit diagram of a wind power converter device 11.

[0144] The wind power converter device 11 includes: grid-side converters 110A-110D, machine-side converters 112A-112B, and a DC bus module. In one embodiment, the grid-side converters 110A-110D include the same components, and the grid-side converter can be a two-level converter. The grid-side converters 110A-110D are electrically coupled to the power grid 16, and any two adjacent grid-side converters are connected in series through the first DC input port IN1 and the second DC input port IN2. Taking the grid-side converters 110A and 110B as an example, the second DC input port IN2 of the grid-side converter 110A is connected in series with the first DC input port IN1 of the grid-side converter 110B.

[0145] Similarly, the second DC input port IN2 of the grid-side converter 110B is connected in series with the first DC input port IN1 of the grid-side converter 110C. Similarly, the second DC input port IN2 of the grid-side converter 110C is connected in series with the first DC input port IN1 of the grid-side converter 110D.

[0146] In one embodiment, the machine-side converters 112A-112B may include the same components, and the machine-side converter can be a three-level converter. The machine-side converter is electrically coupled to the generator device 18. The second DC output port OUT2 of the machine-side converter 112A is connected in series with the first DC output port OUT1 of the machine-side converter 112B.

[0147] The DC bus module includes DC buses 1100, 1101, 1102, 1103, and 1104. Among them, DC bus 1100 is electrically coupled between the first DC input port IN1 of the grid-side converter 110A and the first DC output port OUT1 of the machine-side converter 112A, and this DC bus 1100 is the positive DC bus. DC bus 1102 is electrically coupled between the second DC input port IN2 of the grid-side converter 110D and the second DC output port OUT2 of the machine-side converter 112B, and this DC bus 1102 is the negative DC bus. And DC bus 1101 is electrically coupled between the second DC midpoint OUT0 of the machine-side converter 112A and the first DC input port IN1 of the grid-side converter 110B, DC bus 1103 is electrically coupled between the second DC output port OUT2 of the machine-side converter 112A and the second DC input port IN2 of the grid-side converter 110B, and DC bus 1104 is electrically coupled between the second DC midpoint OUT0 of the machine-side converter 112B and the first DC input port IN1 of the grid-side converter 110D. Among them, DC buses 1101, 1103, and 1104 are intermediate DC buses.

[0148] Therefore, the machine-side control modules 111A - 111B included in the wind power converter device 11 can adopt Figure 7 the mechanism to control the machine-side converters 112A - 112B.

[0149] In an embodiment, the wind power converter device 1 further includes chopper circuits 113A to 113D, and the chopper circuits 113A to 113D are respectively connected in parallel between the first DC output port OUT1 and the second DC midpoint OUT0 of the machine-side converter 112A, between the second DC output port OUT2 and the second DC midpoint OUT0 of the machine-side converter 112A, between the first DC output port OUT1 and the second DC midpoint OUT0 of the machine-side converter 112B, and between the second DC output port OUT2 and the second DC midpoint OUT0 of the machine-side converter 112B, for performing voltage equalization protection on the machine-side converters 112A and 112B.

[0150] Therefore, from Figures 8 to 12 the embodiments, it can be seen that the design of the wind power converter device can be flexibly adjusted according to the requirements of actual applications and is not limited by a specific structure.

[0151] Although the present disclosure has been disclosed as above in an implementation manner, it is not intended to limit the present disclosure. Any person skilled in the art can make various changes and modifications without departing from the concept and scope of the present disclosure. Therefore, the protection scope of the present disclosure shall be subject to the scope defined by the claims.

Claims

1. A wind power converter device, comprising: A plurality of grid-side converters, arranged under the tower of a wind power system, and each comprising a plurality of grid-side output ports electrically coupled to a power grid, a first DC input port, and a second DC input port, and the second DC input port of one of any two adjacent grid-side converters is connected in series with the first DC input port of the other; A plurality of machine-side converters, arranged on the tower of the wind power system, and each comprising a machine-side input port electrically coupled to a generator device, a first DC output port, and a second DC output port, and the second DC output port of one of any two adjacent machine-side converters is connected in series with the first DC output port of the other; and A DC bus module, comprising a plurality of DC buses, electrically coupled between the grid-side converters and the machine-side converters; Among them, The corresponding grid-side converter, the corresponding machine-side converter, and the DC bus module establish at least one power transmission path between the power grid and the generator device, wherein power is transmitted between the power grid and the generator device through the power transmission path; At least one active circuit protection element, arranged in the DC bus module; and At least one detection circuit, arranged in the DC bus module, the detection circuit is used to detect whether the power on the corresponding power transmission path is abnormal, and when an abnormality is detected, output a corresponding abnormal signal, so that the corresponding active circuit protection element is switched to an open state according to the abnormal signal.

2. The wind power converter device according to claim 1, wherein the active circuit protection element is a relay or a switch element, and the detection circuit is a current sensor.

3. The wind power converter device according to claim 1, wherein the active circuit protection element is arranged on the corresponding DC bus.

4. The wind power converter device according to claim 3, wherein the detection circuit is arranged on the corresponding DC bus.

5. A wind power converter device, comprising: A plurality of grid-side converters, arranged under the tower of a wind power system, and each comprising a plurality of grid-side output ports electrically coupled to a power grid, a first DC input port, and a second DC input port, and the second DC input port of one of any two adjacent grid-side converters is connected in series with the first DC input port of the other; A plurality of machine-side converters, arranged on the tower of the wind power system, and each comprising a machine-side input port electrically coupled to a generator device, a first DC output port, and a second DC output port, and the second DC output port of one of any two adjacent machine-side converters is connected in series with the first DC output port of the other; A DC bus module, comprising a plurality of DC buses, electrically coupled between the grid-side converters and the machine-side converters; and Multiple machine-side control modules communicate with each other and respectively control the operation of corresponding machine-side converters. Each machine-side control module is preset with a protection condition. When the operating conditions of the machine-side converter corresponding to the machine-side control module and / or the grid-side converter electrically coupled to the corresponding machine-side converter reach the protection condition, the machine-side control module stops outputting three-phase voltage control signals to stop the operation of the corresponding machine-side converter. The protection condition is detecting a DC fault in a power transmission path, and the power transmission path is established by the corresponding grid-side converter, the corresponding machine-side converter, and the DC bus module.

6. The wind power converter device according to claim 5, wherein when any one of the machine-side control modules stops outputting the three-phase voltage control signals, the other normally operating machine-side control modules further drive the corresponding machine-side converters to jointly share the operation required by the machine-side converter that stops outputting the three-phase voltage control signals.

7. The wind power converter device according to claim 5, wherein each of the machine-side control modules is further configured to receive and generate the three-phase voltage control signals to control the operation of the corresponding machine-side converter according to a three-phase input current amount and a second axial general given current component at the machine-side input port of the corresponding machine-side converter.

8. The wind power converter device according to claim 7, wherein each of the machine-side control modules includes: A current extraction unit for extracting the three-phase input current amount; A first conversion unit for converting the three-phase input current amount into a first axial current component and a second axial current component; A first calculation unit for calculating and generating a first axial difference according to the first axial current component and a first axial independent given current component; A second calculation unit for calculating and generating a second axial difference according to the second axial current component and the second axial general given current component; A first current control unit for generating a first axial voltage control signal according to the first axial difference; A second current control unit for generating a second axial voltage control signal according to the second axial difference; and A second conversion unit for converting the first axial voltage control signal and the second axial voltage control signal into the three-phase voltage control signals.

9. The wind power converter device according to claim 8, wherein the first conversion unit includes a dq rotating coordinate of a d-axis and a q-axis, the first axial current component corresponds to a reactive current component on the d-axis, and the second axial current component corresponds to an active current component on the q-axis.

10. The wind power converter device according to claim 1 or 5, wherein the number of the grid-side converters and the machine-side converters is both n, n≥2; and the DC bus includes a positive DC bus, a negative DC bus, and at least one intermediate DC bus between the positive DC bus and the negative DC bus bracket. The first DC input port of the first grid-side converter is electrically coupled to the first DC output port of the first machine-side converter through the positive DC bus; the second DC input port of the nth grid-side converter is electrically coupled to the second DC output port of the nth machine-side converter through the negative DC bus; and the second DC input port of the (n - 1)th grid-side converter is electrically coupled to the second DC output port of the (n - 1)th machine-side converter through the intermediate DC bus.

11. The wind power converter device according to claim 1, further comprising a plurality of machine-side control modules, each of the machine-side control modules being configured to receive and generate a three-phase voltage control signal to control the operation of the corresponding machine-side converter according to a three-phase input current amount and a second axial general given current component of the machine-side input port corresponding to the machine-side converter.

12. The wind power converter device according to claim 11, wherein each of the machine-side control modules comprises: a current extraction unit configured to extract the three-phase input current amount; a first conversion unit configured to convert the three-phase input current amount into a first axial current component and a second axial current component; a first calculation unit configured to calculate and generate a first axial difference according to the first axial current component and a first axial independent given current component; a second calculation unit configured to calculate and generate a second axial difference according to the second axial current component and the second axial general given current component; a first current control unit configured to generate a first axial voltage control signal according to the first axial difference; a second current control unit configured to generate a second axial voltage control signal according to the second axial difference; and a second conversion unit configured to convert the first axial voltage control signal and the second axial voltage control signal into the three-phase voltage control signal.

13. The wind power converter device according to claim 12, wherein the first conversion unit comprises a dq rotation coordinate of a d-axis and a q-axis, the first axial current component corresponds to a reactive current component on the d-axis, and the second axial current component corresponds to an active current component on the q-axis.

14. The wind power converter device according to claim 1 or 5, wherein the DC bus module comprises a plurality of first bus capacitor groups and a plurality of second bus capacitor groups, wherein the first bus capacitor groups correspond to the grid-side converters one by one, and each first bus capacitor group is connected in parallel between the first DC input port and the second DC input port of the corresponding grid-side converter; the second bus capacitor groups correspond to the machine-side converters one by one, and each second bus capacitor group is connected in parallel between the first DC output port and the second DC output port of the corresponding machine-side converter.

15. The wind power converter device according to claim 1 or 5, wherein the generator device comprises a plurality of sets of windings, and each set of the plurality of sets of windings is electrically coupled to the machine-side input port of the corresponding machine-side converter.

16. The wind power converter device according to claim 1 or 5, wherein the machine side converter is a two-level converter and the grid side converter is a two-level converter; or the machine side converter is a three-level converter and the grid side converter is a three-level converter.

17. The wind power converter device according to claim 16, further comprising a plurality of chopper circuits, and the chopper circuits are connected in parallel between the first DC output port and the second DC output port of the machine side converter.

18. The wind power converter device according to claim 7, wherein the machine side control module includes a main machine side control module and at least one slave machine side control module, and the main machine side control module outputs the second axial general given current component to the at least one slave machine side control module respectively.

19. The wind power converter device according to claim 9, wherein the machine side control module includes a main machine side control module and at least one slave machine side control module, and the main machine side control module generates and outputs the second axial general given current component to the at least one slave machine side control module respectively.

20. The wind power converter device according to claim 1 or 5, wherein the number of the grid side converters is n and the number of the machine side converters is 2n, and the grid side converter further includes a first DC midpoint, where n≥1; and the DC bus includes a positive DC bus, a negative DC bus and at least one intermediate DC bus between the positive DC bus and the negative DC bus; Among them, The first DC input end of the first grid side converter is electrically coupled to the first DC output end of the first machine side converter through the positive DC bus; the second DC input port of the nth grid side converter is electrically coupled to the second DC output end of the 2nth machine side converter through the negative DC bus; and between the first DC midpoint of the nth grid side converter and the first DC output end of the 2nth machine side converter, and between the second DC input port of the (n - 1)th grid side converter and the first DC output end of the (2n - 1)th machine side converter are electrically coupled through the intermediate DC bus.

21. The wind power converter device according to claim 1 or 5, wherein the number of the grid side converters is 2n and the number of the machine side converters is n, and the machine side converter further includes a second DC midpoint, where n≥1; and the DC bus includes a positive DC bus, a negative DC bus and at least one intermediate DC bus between the positive DC bus and the negative DC bus; Among them, The first DC input end of the first grid side converter is electrically coupled to the first DC output end of the first machine side converter through the positive DC bus; the second DC input port of the 2nth grid side converter is electrically coupled to the second DC output end of the nth machine side converter through the negative DC bus; and between the first DC input port of the 2nth grid side converter and the second DC midpoint of the nth machine side converter, and between the first DC input port of the (2n - 1)th grid side converter and the second DC output end of the nth machine side converter are electrically coupled through the intermediate DC bus.

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