CN211826314U - Wind turbine generator system testing arrangement that is incorporated into power networks - Google Patents
Wind turbine generator system testing arrangement that is incorporated into power networks Download PDFInfo
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- CN211826314U CN211826314U CN202020129604.7U CN202020129604U CN211826314U CN 211826314 U CN211826314 U CN 211826314U CN 202020129604 U CN202020129604 U CN 202020129604U CN 211826314 U CN211826314 U CN 211826314U
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Abstract
The application discloses wind turbine generator system testing arrangement that is incorporated into power networks includes: a grid disturbance generating device connected to the grid side; the power grid fault simulation generating device is respectively connected with the tested wind turbine generator set and the power grid disturbance generating device; the test device comprehensive monitoring system is respectively in communication connection with the power grid disturbance generating device and the power grid fault simulation generating device; the power grid disturbance generating device is used for testing the power grid adaptability of the tested wind generating set; the power grid disturbance generating device and the power grid fault simulation generating device are combined and used for testing the fault voltage ride through capability of the tested wind turbine generator; the comprehensive monitoring system of the testing device is used for carrying out state monitoring and remote control on the power grid disturbance generating device and the power grid fault simulation generating device. This application carries out integrated design through simulating generating device with electric wire netting disturbance and electric wire netting trouble, can better optimize testing arrangement's performance, improves efficiency of software testing, reduces the overall cost of device, improves the reliability of device.
Description
Technical Field
The application relates to the technical field of fan testing, in particular to a wind turbine generator grid-connected testing device.
Background
In order to avoid fan grid disconnection accidents caused by low voltage low-voltage ride through of wind turbine generators and insufficient power grid adaptability, test detection means are commonly adopted at present to ensure that the wind turbine generators connected into a power grid meet the operation requirements of the power grid, reduce the risk of abnormal grid disconnection of the wind turbine generators/wind power plants and improve the safe operation of the power grid containing large-scale wind power plant access. The grid-connected testing device of the wind turbine generator is key equipment for realizing the grid-connected performance test of the wind turbine generator, and is widely concerned by domestic and foreign scholars and equipment manufacturers.
In the existing scheme, a power grid disturbance generating device is generally adopted to test the power grid adaptability of the wind turbine generator, and a power grid fault simulation device is adopted to test the fault voltage ride-through capability of the wind turbine generator. The power grid disturbance generating device and the power grid fault simulation device are generally realized independently by two sets of devices at present, the design is relatively independent, and the test is carried out separately in the test process, so that the equipment cost is high, the test speed is low, and the efficiency is low.
SUMMERY OF THE UTILITY MODEL
The embodiment of the application provides a wind turbine generator system grid-connected testing device, so that the performance of the testing device is optimized, the testing efficiency is improved, the overall cost of the device is reduced, and the reliability of the device is improved.
In view of this, the present application provides a wind turbine generator system grid-connected testing device, the device includes:
a grid disturbance generating device connected to the grid side;
the power grid fault simulation generation device is respectively connected with the tested wind turbine generator set and the power grid disturbance generation device;
the test device comprehensive monitoring system is respectively in communication connection with the power grid disturbance generating device and the power grid fault simulation generating device;
the power grid disturbance generating device is used for testing the power grid adaptability of the tested wind generating set;
the power grid disturbance generating device and the power grid fault simulation generating device are combined and used for testing the fault voltage ride through capability of the tested wind turbine generator;
and the comprehensive monitoring system of the testing device is used for carrying out state monitoring and remote control on the power grid disturbance generating device and the power grid fault simulation generating device.
Optionally, the power grid adaptability comprises wind turbine generator set voltage deviation adaptability, frequency deviation adaptability, three-phase voltage unbalance adaptability, flicker adaptability and harmonic voltage adaptability.
Optionally, the fault voltage ride through capability includes low voltage ride through, high voltage ride through, and voltage cascading fault test of the wind turbine generator.
Optionally, the grid disturbance generating device includes a first circuit breaker, an ac/dc/ac power electronic power converter and a second circuit breaker that are sequentially connected in series, and further includes a first bypass circuit breaker that is connected in parallel to both ends of the first circuit breaker, the ac/dc/ac power electronic power converter that are sequentially connected in series.
Optionally, the ac/dc/ac power electronic power converter includes a first coupling transformer, and three first phase units connected to a three-phase output of the first coupling transformer, where the three first phase units are connected in parallel;
the three-phase transformer is connected with the three second-phase units respectively, the three second-phase units are connected in parallel, the first-phase unit is connected with the smoothing reactor, and the other end of the smoothing reactor is connected with the second-phase unit.
Optionally, the phase unit includes several sub-modules.
Optionally, the sub-module is a half-bridge sub-module, a full-bridge sub-module, or a clamping type dual sub-module circuit.
Optionally, the grid fault simulation generating device includes:
the third circuit breaker, the current-limiting reactor and the fourth circuit breaker are sequentially connected in series;
and the second bypass circuit breakers are connected in parallel with the third circuit breaker, the current-limiting reactor and the fourth circuit breaker which are sequentially connected in series.
Optionally, one end of the current-limiting reactance is connected to a fifth circuit breaker and a sixth circuit breaker;
the other end of the fifth circuit breaker is connected with a short-circuit reactor, and the other end of the short-circuit reactor is grounded;
the sixth circuit breaker, the boost branch capacitor and the boost branch resistor are sequentially connected in series, and the other end of the boost branch resistor is grounded.
Optionally, the output of the power grid side is connected with the other end of the first circuit breaker, the other end of the second circuit breaker is connected with the other end of the third circuit breaker, and the other end of the fourth circuit breaker is connected with the tested wind turbine generator set.
According to the technical scheme, the method has the following advantages:
the application provides a wind turbine generator grid-connected testing device which comprises a power grid disturbance generating device connected with a power grid side; the power grid fault simulation generation device is respectively connected with the tested wind turbine generator set and the power grid disturbance generation device; the test device comprehensive monitoring system is respectively in communication connection with the power grid disturbance generating device and the power grid fault simulation generating device; the power grid disturbance generating device is used for testing the power grid adaptability of the tested wind generating set; the power grid disturbance generating device and the power grid fault simulation generating device are combined and used for testing the fault voltage ride through capability of the tested wind turbine generator; and the comprehensive monitoring system of the testing device is used for carrying out state monitoring and remote control on the power grid disturbance generating device and the power grid fault simulation generating device.
This application carries out the integrated design with electric wire netting disturbance generating device and electric wire netting fault simulation generating device, can better optimize testing arrangement's performance, improves efficiency of software testing, reduces the overall cost of device, improves the reliability of device.
Drawings
Fig. 1 is a schematic structural diagram of an embodiment of a wind turbine grid-connected testing device according to the present application;
fig. 2 is a schematic circuit diagram of a power grid disturbance generating device in an embodiment of a wind turbine grid-connected testing device according to the present application;
FIG. 3 is a schematic circuit diagram of an AC/DC/AC power electronic power converter according to an embodiment of the wind turbine grid-connected testing apparatus of the present application;
FIG. 4 is a schematic circuit diagram of a submodule in an AC/DC/AC power electronic power converter of the present application;
fig. 5 is a schematic circuit diagram of a grid fault simulation generation apparatus according to the present application;
fig. 6 is a schematic diagram illustrating a connection between a grid disturbance generating device and a grid fault simulation generating device according to the present application;
fig. 7 is a flowchart of a main circuit parameter design method of the grid-connected test device according to the present application.
Detailed Description
In order to make the technical solutions of the present application better understood, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
Referring to fig. 1, fig. 1 is a schematic structural diagram of an embodiment of a wind turbine grid connection testing device, as shown in fig. 1, in fig. 1:
and the power grid disturbance generating device is connected with the power grid side.
It should be noted that the grid disturbance generating device may include a first circuit breaker, an ac/dc/ac power electronic power converter, a second circuit breaker, and a first bypass circuit breaker connected in parallel to two ends of the first circuit breaker, the ac/dc/ac power electronic power converter, which are sequentially connected in series. The ac/dc/ac power electronic power converter is a multi-level power converter capable of implementing ac/dc/ac two-stage conversion, and is specifically shown in fig. 2, in which the breaker QF11 is a first breaker, the breaker QF12 is a second breaker, and the bypass breaker QF13 is a first bypass breaker.
In a specific embodiment, fig. 3 is an implementation of a Modular Multilevel Converter (MMC) -based Converter. Wherein, AC/DC/AC power electronic power converter can include: the three first phase units are connected in parallel; the three-phase transformer is connected with the three second-phase units respectively, the three second-phase units are connected in parallel, the first-phase unit is connected with the smoothing reactor, and the other end of the smoothing reactor is connected with the second-phase unit. The connection transformer on the left side in fig. 3 is a first connection transformer, and the phase unit connected to the first connection transformer is a first phase unit; the right connection transformer in fig. 3 is a second connection transformer, and the phase unit connected to the second connection transformer is a second phase unit. It should be noted that the ac/dc/ac power electronic power converter of the grid disturbance generating device is not limited to the modular multilevel structure shown in fig. 3, and as long as the grid adaptability test function of the wind turbine generator system can be realized, all power electronic power converter circuits capable of realizing the ac/dc/ac power conversion function may be replaced.
In a specific embodiment, a phase unit in an ac/dc/ac power electronic power converter includes several sub-modules, which may be half-bridge or full-bridge or clamped dual sub-module circuits. Specifically, as shown in fig. 4, fig. 4(a) is a half-bridge sub-module, fig. 4(b) is a full-bridge sub-module, and fig. 4(c) is a clamping type bi-sub-module circuit.
And the power grid fault simulation generating device is respectively connected with the tested wind turbine generator set and the power grid disturbance generating device.
It should be noted that the grid fault simulation generation device may include: the third circuit breaker, the current-limiting reactance and the fourth circuit breaker are sequentially connected in series; and the second bypass circuit breaker is connected in parallel with the third circuit breaker, the current-limiting reactance and the two ends of the fourth circuit breaker which are sequentially connected in series. One end of the current-limiting reactor is connected with the fifth circuit breaker and the sixth circuit breaker; the other end of the fifth circuit breaker is connected with a short-circuit reactor, and the other end of the short-circuit reactor is grounded; and the sixth circuit breaker, the boosting branch capacitor and the boosting branch resistor are sequentially connected in series with the other end of the boosting branch resistor to be grounded. The breaker QF21 is a third breaker, the breaker QF22 is a fourth breaker, the breaker QF24 is a fifth breaker, the breaker QF25 is a sixth breaker, and the bypass breaker QF23 is a second bypass breaker. The main circuit structure of the grid fault simulation generation device is shown in fig. 5.
The design of parameters of a current-limiting reactance, a short-circuit reactance and a boost branch capacitor in a circuit of a power grid fault simulation generating device is most critical and most complex, and the main reason is that short-circuit capacity parameters on the power grid side are greatly different in different test environments, some wind power plants are in remote areas, the system is weak, the short-circuit capacity is only dozens of MVA (multi-domain vertical axis), some wind power plants are strong in the system accessed in the wind power plant, and the short-circuit capacity can reach hundreds of MVA (multi-domain vertical axis). Therefore, when the fault voltage ride-through capability of the wind turbine generator is tested, the grid disturbance generating device and the grid fault simulation generating device are connected at the same time, as shown in fig. 6, because the grid fault simulation generating device is connected with the grid through the grid disturbance generating device, the ac/dc/ac power electronic power converter of the grid disturbance generating device realizes the isolation between the grid and the grid fault simulation generating device, that is, the ac/dc/ac power electronic power converter can be regarded as a voltage source with fixed short-circuit capacity for the grid fault simulation generating device, and the grid fault simulation generating device is no longer influenced by the short-circuit capacity at the side of the grid, so that the parameter design of the current-limiting reactance, the short-circuit reactance and the boost branch capacitance of the grid fault simulation generating device is greatly simplified.
In a specific embodiment, the output of the power grid side is connected with the other end of the first circuit breaker, the other end of the second circuit breaker is connected with the other end of the third circuit breaker, and the other end of the fourth circuit breaker is connected with the tested wind generating set.
And the test device comprehensive monitoring system is respectively in communication connection with the power grid disturbance generating device and the power grid fault simulation generating device.
It should be noted that the integrated monitoring system of the testing device can monitor the electrical signals in the power grid disturbance generating device and the power grid fault simulation generating device in real time, and can analyze the electrical signals to remotely control the power grid disturbance generating device and the power grid fault simulation generating device.
And the power grid disturbance generating device is used for testing the power grid adaptability of the tested wind generating set.
It should be noted that the grid disturbance generating device may be designed between the grid side and the grid fault simulation generating device, so as to isolate the grid side from the grid fault simulation generating device, and may be used to measure the adaptability of the wind turbine. The power grid adaptability can comprise wind turbine generator set voltage deviation adaptability, frequency deviation adaptability, three-phase voltage unbalance adaptability, flicker adaptability and harmonic voltage adaptability.
And the power grid disturbance generating device and the power grid fault simulation generating device are combined and used for testing the fault voltage ride-through capability of the tested wind turbine generator system.
It should be noted that, the power grid disturbance generating device and the power grid fault simulation generating device are combined, and the performance of the testing device can be better optimized, the testing efficiency is improved, the overall cost of the device is reduced, and the reliability of the device is improved by integrally designing the power grid disturbance generating device and the power grid fault simulation generating device. The fault voltage ride-through capability can comprise low voltage ride-through, high voltage ride-through and voltage cascading fault testing of the wind turbine generator.
The comprehensive monitoring system of the testing device is used for carrying out state monitoring and remote control on the power grid disturbance generating device and the power grid fault simulation generating device.
It should be noted that the integrated monitoring system of the testing device can be in communication connection with the power grid disturbance generating device and the power grid fault simulation generating device, an input port of the integrated monitoring system of the testing device can be connected between the power grid side and the power grid disturbance generating device, and an output port of the integrated monitoring system of the testing device can be connected between the tested wind turbine generator set and the power grid fault simulation generating device, so that the state monitoring and remote control of the power grid disturbance generating device and the power grid fault simulation generating device are realized.
This application carries out integrated design through simulating generating device with electric wire netting disturbance and electric wire netting trouble, can better optimize testing arrangement's performance, improves efficiency of software testing, reduces the overall cost of device, improves the reliability of device.
The application also includes a method for designing main circuit parameters of the grid-connected testing device, and reference can be made to fig. 7. The method specifically comprises the following steps: and designing main circuit parameters of the power grid disturbance generating device according to the type and the maximum capacity of the wind turbine generator to be tested by the grid-connected testing device, the power grid adaptability testing function and the performance index requirements, and calculating short circuit impedance parameters of the output end of the power grid disturbance generating device. The method comprises the steps of designing main circuit parameters of a power grid fault simulation generating device according to the type and the maximum capacity of a wind turbine generator to be tested by a grid-connected testing device, short-circuit impedance parameters of an output end of the power grid disturbance generating device, a fault voltage ride-through capability testing function and performance index requirements. The main circuit parameters of the integrated wind turbine generator grid-connected testing device can be finally obtained according to the main circuit parameters of the power grid disturbance generating device and the main circuit parameters of the power grid fault simulation generating device.
It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.
The terms "first," "second," "third," "fourth," and the like in the description of the application and the above-described figures, if any, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the application described herein are, for example, capable of operation in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.
It should be understood that in the present application, "at least one" means one or more, "a plurality" means two or more. "and/or" for describing an association relationship of associated objects, indicating that there may be three relationships, e.g., "a and/or B" may indicate: only A, only B and both A and B are present, wherein A and B may be singular or plural. The character "/" generally indicates that the former and latter associated objects are in an "or" relationship. "at least one of the following" or similar expressions refer to any combination of these items, including any combination of single item(s) or plural items. For example, at least one (one) of a, b, or c, may represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", wherein a, b, c may be single or plural.
The above embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions in the embodiments of the present application.
Claims (10)
1. The utility model provides a wind turbine generator system testing arrangement that is incorporated into power networks which characterized in that includes:
a grid disturbance generating device connected to the grid side;
the power grid fault simulation generation device is respectively connected with the tested wind turbine generator set and the power grid disturbance generation device;
the test device comprehensive monitoring system is respectively in communication connection with the power grid disturbance generating device and the power grid fault simulation generating device;
the power grid disturbance generating device is used for testing the power grid adaptability of the tested wind generating set;
the power grid disturbance generating device and the power grid fault simulation generating device are combined and used for testing the fault voltage ride through capability of the tested wind turbine generator;
and the comprehensive monitoring system of the testing device is used for carrying out state monitoring and remote control on the power grid disturbance generating device and the power grid fault simulation generating device.
2. The wind turbine generator system grid-connection testing device according to claim 1, wherein the grid adaptability includes wind turbine generator system voltage deviation adaptability, frequency deviation adaptability, three-phase voltage unbalance adaptability, flicker adaptability and harmonic voltage adaptability.
3. The wind turbine grid-connected testing device according to claim 1, wherein the fault voltage ride-through capability comprises wind turbine low voltage ride-through, high voltage ride-through and voltage cascading fault testing.
4. The wind turbine grid-connected testing device according to claim 1, wherein the grid disturbance generating device comprises a first circuit breaker, an ac/dc/ac power electronic power converter and a second circuit breaker which are sequentially connected in series, and further comprises a first bypass circuit breaker which is connected in parallel to two ends of the first circuit breaker and the ac/dc/ac power electronic power converter which are sequentially connected in series.
5. The wind turbine grid-connection testing device according to claim 4, wherein the AC/DC/AC power electronic power converter comprises a first connection transformer, and three first phase units connected to a three-phase output of the first connection transformer, and the three first phase units are connected in parallel;
the three-phase transformer is connected with the three second-phase units respectively, the three second-phase units are connected in parallel, the first-phase unit is connected with the smoothing reactor, and the other end of the smoothing reactor is connected with the second-phase unit.
6. The wind turbine grid-connection testing device according to claim 5, wherein the phase unit comprises a plurality of submodules.
7. The wind turbine generator system grid-connection testing device according to claim 6, wherein the sub-module is a half-bridge sub-module, a full-bridge sub-module or a clamping type dual sub-module circuit.
8. The wind turbine grid-connection testing device according to claim 4, wherein the grid fault simulation generating device comprises:
the third circuit breaker, the current-limiting reactor and the fourth circuit breaker are sequentially connected in series;
and the second bypass circuit breakers are connected in parallel with the third circuit breaker, the current-limiting reactor and the fourth circuit breaker which are sequentially connected in series.
9. The wind turbine grid-connection testing device according to claim 8,
one end of the current-limiting reactor is connected with a fifth circuit breaker and a sixth circuit breaker;
the other end of the fifth circuit breaker is connected with a short-circuit reactor, and the other end of the short-circuit reactor is grounded;
the sixth circuit breaker, the boost branch capacitor and the boost branch resistor are sequentially connected in series, and the other end of the boost branch resistor is grounded.
10. The wind turbine grid-connected testing device according to claim 8, wherein the output of the grid side is connected to the other end of the first circuit breaker, the other end of the second circuit breaker is connected to the other end of the third circuit breaker, and the other end of the fourth circuit breaker is connected to the tested wind turbine.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114295914A (en) * | 2021-12-30 | 2022-04-08 | 深圳市首航新能源股份有限公司 | Test verification method and test verification platform for grid-connected electronic equipment |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114295914A (en) * | 2021-12-30 | 2022-04-08 | 深圳市首航新能源股份有限公司 | Test verification method and test verification platform for grid-connected electronic equipment |
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