A power cycle test circuit and method for series valves

Abstract

The present invention provides a power cycle test circuit and method for a series valve, comprising a voltage source, a first auxiliary valve, a second auxiliary valve, a first test valve, a second test valve, a test valve, a load inductor, and a coupling inductor; the anode of the first test valve, the cathode of the second auxiliary valve, and the anode of the second test valve are all connected to the positive electrode of the voltage source; the anode of the first auxiliary valve and the common end of the coupling inductor are both connected to the negative electrode of the voltage source; the first end of the load inductor and the cathode of the first auxiliary valve are both connected to the cathode of the first test valve; the anode of the second auxiliary valve and the anode of the test valve are both connected to the second end of the load inductor; the cathode of the test valve is connected to the primary side of the coupling inductor; and the cathode of the second test valve is connected to the secondary side of the coupling inductor. Through the above embodiment, the electrical performance of the series valve can be quickly verified while reducing the complexity and cost of the circuit.

Description

Technical Field

[0001] The present invention relates to the technical field of power electronic valve operation testing, and in particular to a power cycle testing circuit and method for a series valve. Background Art

[0002] Currently, traditional HVDC converters use a three-phase bridge rectifier composed of thyristors as the basic unit. Each bridge arm consists of a thyristor valve string. Because the thyristor valve string cannot actively control current shutoff, the converter has large commutation currents and reactive power support, which poses a risk of commutation failure and requires improved reliability. To address this issue, a new HVDC hybrid converter has emerged. This new HVDC hybrid converter comprises a series connection of thyristors and gate-off valves. The gate-off valves can include one or more reverse-blocking integrated gate-commutated thyristors (IGCTs), gate-off thyristors (GTOs), or improved insulated-gate bipolar transistors (IGBTs). Alternatively, they can be a combination of non-reverse-blocking IGCTs, GTOs, or IGBTs in series with a diode. To verify that the performance of its core components meets the technical specifications of DC projects, the series valve string requires necessary electrical performance testing. Existing converter valve synthetic test circuits can test various operating conditions of series-connected valves, detect the voltage and current stresses of the valve train, and optimize parameters. However, these test circuits do not consider conditions where the active shutoff element can enhance recovery when the valve train fails to recover from blocking. Furthermore, these test circuits require the construction of a current source circuit, which requires a large power supply capacity and is complex to control. This hinders rapid verification of the electrical performance of series-connected valves. Therefore, a solution is needed to quickly verify the electrical performance of series-connected valves while reducing circuit complexity and cost. Summary of the Invention

[0003] The object of the present invention is to provide a power cycle test circuit and method for a series valve, so as to achieve the technical effect of quickly verifying the electrical performance of the series valve while reducing the complexity and cost of the circuit.

[0004] In a first aspect, the present invention provides a power cycle test circuit for a series valve, comprising a voltage source, a first auxiliary valve, a second auxiliary valve, a first test valve, a second test valve, a test valve, a load inductor and a coupling inductor; the anode of the first test valve, the cathode of the second auxiliary valve and the anode of the second test valve are all connected to the positive electrode of the voltage source; the anode of the first auxiliary valve and the common end of the coupling inductor are both connected to the negative electrode of the voltage source; the first end of the load inductor and the cathode of the first auxiliary valve are both connected to the cathode of the first test valve; the anode of the second auxiliary valve and the anode of the test valve are both connected to the second end of the load inductor; the cathode of the test valve is connected to the primary side of the coupling inductor; and the cathode of the second test valve is connected to the secondary side of the coupling inductor.

[0005] Optionally, the first test valve is composed of a component of any type among an IGBT device, an IGCT device and an IEGT device.

[0006] Optionally, the second test valve is composed of a component of any type among an IGBT device, an IGCT device and an IEGT device.

[0007] Optionally, the first test valve is composed of a plurality of components of the same type among IGBT devices, IGCT devices and IEGT devices connected in series.

[0008] Optionally, the second test valve is composed of a plurality of components of the same type among IGBT devices, IGCT devices and IEGT devices connected in series.

[0009] Optionally, the test valve is composed of a component of any type among an IGBT device, an IGCT device and an IEGT device connected in series with a thyristor.

[0010] Optionally, the first auxiliary valve and the second auxiliary valve are diode valve strings.

[0011] In a second aspect, the present invention provides a power cycle test method for a series valve, which is applied to the power cycle test circuit of the series valve, comprising:

[0012] Triggering to open the first accompanying test valve and the tested valve, and when the current in the tested valve rises to a set value, triggering to close the first accompanying test valve;

[0013] When the duration of the current in the tested valve reaches a set value, the second accompanying test valve is triggered to open;

[0014] When the current in the tested valve is less than the set value or equals to 0, the second accompanying test valve and the tested valve are triggered to be closed.

[0015] The present invention achieves the following beneficial effects: The power cycle test circuit for the series valve provided by the present invention can first trigger the opening of the first test valve and the test valve during the test. When the current in the test valve rises to a set value, the first test valve is triggered to close. When the current duration in the test valve reaches a set value, the second test valve is triggered to open. When the current in the test valve is less than the set value or reaches 0, the second test valve and the test valve are triggered to close. This method can quickly verify the electrical performance of the series valve, while simplifying the circuit and reducing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments of the present invention. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0017] Figure 1 A schematic diagram of the topological structure of a power cycle test circuit for a series valve provided by an embodiment of the present invention;

[0018] Figure 2 A schematic diagram of a power cycle test circuit for a first series valve provided by an embodiment of the present invention;

[0019] Figure 3 A schematic diagram of a power cycle test circuit for a second series valve provided by an embodiment of the present invention;

[0020] Figure 4 A schematic diagram of a power cycle test circuit for a third series valve provided by an embodiment of the present invention;

[0021] Figure 5 A flow chart of a power cycle test method for a series valve provided in an embodiment of the present invention.

[0022] Icon: 10-power cycle test circuit; 100-voltage source; 200-first auxiliary valve; 300-second auxiliary valve; 400-first accompanying test valve; 500-second accompanying test valve; 600-test valve; 700-load inductor; 800-coupling inductor. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present invention will be described below with reference to the accompanying drawings in the embodiments of the present invention.

[0024] It should be noted that similar reference numerals and letters represent similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings. At the same time, in the description of the present invention, the terms "first", "second", etc. are used only to distinguish the description and should not be understood as indicating or implying relative importance.

[0025] Please see Figure 1 , Figure 1 A schematic diagram of the topological structure of a power cycle test circuit for a series valve provided in an embodiment of the present invention.

[0026] In one embodiment, a power cycle test circuit 10 for a series valve provided in an embodiment of the present invention includes a voltage source 100, a first auxiliary valve 200, a second auxiliary valve 300, a first test valve 400, a second test valve 500, a test valve 600, a load inductor 700, and a coupling inductor 800; the anode of the first test valve 400, the cathode of the second auxiliary valve 300, and the anode of the second test valve 500 are all connected to the positive electrode of the voltage source 100; the anode of the first auxiliary valve 200 and the common end of the coupling inductor 800 are both connected to the negative electrode of the voltage source 100; the first end of the load inductor 700 and the cathode of the first auxiliary valve 200 are both connected to the cathode of the first test valve 400; the anode of the second auxiliary valve 300 and the anode of the test valve 600 are both connected to the second end of the load inductor 700; the cathode of the test valve 600 is connected to the primary side of the coupling inductor 800; and the cathode of the second test valve 500 is connected to the secondary side of the coupling inductor 800.

[0027] For example, the first auxiliary valve 200 and the second auxiliary valve 300 are diode valve strings. To verify the electrical performance of the test valve 600, the first auxiliary test valve 400 and the test valve 600 are triggered to open. When the current in the test valve 600 rises to a set value, the first auxiliary test valve 400 is triggered to close. When the current in the test valve 600 lasts for a set period, the second auxiliary test valve 500 is triggered to open. When the current in the test valve 600 falls below the set value or reaches zero, the second auxiliary test valve 500 and the test valve 600 are triggered to close, preparing for the next cycle.

[0028] Through the above implementation, the electrical performance of the series valve can be quickly verified, while the circuit is simpler and the cost is reduced.

[0029] In the above implementation process, the first test valve 400 is composed of a component of any type among the IGBT device, the IGCT device, and the IEGT device; or, the first test valve 400 is composed of multiple components of the same type among the IGBT device, the IGCT device, and the IEGT device connected in series. The test valve 600 is composed of a component of any type among the IGBT device, the IGCT device, and the IEGT device connected in series with a thyristor. The second test valve 500 is composed of a component of any type among the IGBT device, the IGCT device, and the IEGT device; or, the second test valve 500 is composed of multiple components of the same type among the IGBT device, the IGCT device, and the IEGT device connected in series.

[0030] Please see Figure 2 , Figure 2 This is a schematic diagram of a power cycle test circuit for a first series valve provided in an embodiment of the present invention.

[0031] For example, in one embodiment, the first test valve 400 is composed of a component of any type among an IGBT device, an IGCT device, and an IEGT device; the tested valve 600 is composed of a component of any type among an IGBT device, an IGCT device, and an IEGT device connected in series with a thyristor; and the second test valve 500 is composed of a component of any type among an IGBT device, an IGCT device, and an IEGT device.

[0032] Specifically, if Figure 2 As shown, the first test valve 400 may be an IGBT device; the tested valve 600 may be an IGCT device connected in series with a thyristor; and the second test valve 500 may be an IEGT device.

[0033] It should be noted that the above embodiment is only one embodiment provided by the present invention. The type of the first test valve 400 and the second test valve 500 can be selected from IGBT devices, IGCT devices, and IEGT devices according to actual needs. At the same time, the IGCT device in the test valve 600 can also be replaced with an IGBT device or an IEGT device according to actual needs. The number of the two components connected in series in the test valve 600 can be adjusted according to actual needs.

[0034] In one embodiment, the first test valve 400 is composed of a component of any type among the IGBT device, IGCT device, and IEGT device; the tested valve 600 is composed of a component of any type among the IGBT device, IGCT device, and IEGT device connected in series with a thyristor; and the second test valve 500 is composed of multiple components of the same type among the IGBT device, IGCT device, and IEGT device connected in series.

[0035] Specifically, the first test valve 400 may be composed of an IGCT device; the tested valve 600 may be composed of an IGBT device and a thyristor connected in series; and the second test valve 500 may be composed of two IGBT devices connected in series.

[0036] It should be noted that the above embodiment is only one embodiment provided by the present invention. In actual use, either the first test valve 400 or the second test valve 500 can use multiple components of the same type connected in series. The number of components connected in series can also be adjusted according to actual needs. The IGBT device in the test valve 600 can also be replaced with an IEGT device or an IGCT device as needed, and the number of the two components connected in series in the test valve 600 can also be adjusted according to actual needs.

[0037] Please see Figure 3 , Figure 3 This is a schematic diagram of a power cycle test circuit for a second series valve provided in an embodiment of the present invention.

[0038] For example, in one embodiment, the first test valve 400 is composed of multiple components of the same type among IGBT devices, IGCT devices, and IEGT devices connected in series; the tested valve 600 is composed of one component of any type among IGBT devices, IGCT devices, and IEGT devices and a thyristor connected in series; and the second test valve 500 is also composed of multiple components of the same type among IGBT devices, IGCT devices, and IEGT devices connected in series.

[0039] Specifically, if Figure 3 As shown, the first test valve 400 is composed of two IGCT devices connected in series, the tested valve 600 is composed of an IEGT device and a thyristor connected in series, and the second test valve 500 is composed of two IGBT devices connected in series.

[0040] It should be noted that the above embodiment is only an exemplary embodiment provided by the present invention. In actual use, the same type of components connected in series in the first test valve 400 and the second test valve 500 can be replaced with IGBT devices or IEGT devices according to actual needs; the IEGT device in the test valve 600 can also be replaced with IGBT devices or IGCT devices according to actual needs. At the same time, the number of the two components connected in series in the test valve 600 can be adjusted according to actual needs.

[0041] Please see Figure 4 , Figure 4 This is a schematic diagram of a power cycle test circuit for a third series valve provided in an embodiment of the present invention.

[0042] For example, in one embodiment, the first test valve 400 is composed of at least two of an IGBT device, an IGCT device, and an IEGT device connected in series; the tested valve 600 is composed of one component of any type of an IGBT device, an IGCT device, and an IEGT device connected in series with a thyristor; and the second test valve 500 is composed of at least two of an IGBT device, an IGCT device, and an IEGT device connected in series.

[0043] Specifically, if Figure 4 As shown, the first test valve 400 is composed of an IGBT device and an IGCT device connected in series, the tested valve 600 is composed of an IGBT device and a thyristor device connected in series, and the second test valve 500 is composed of an IGBT device and an IEGT device connected in series.

[0044] It should be noted that the above embodiment is merely an exemplary embodiment of the present invention. In actual use, the two components connected in series in the first test valve 400 and the second test valve 500 can be selected from any two of the following: IGBT devices, IGCT devices, and IEGT devices, depending on actual needs. Furthermore, the number of each type of component can be adjusted based on actual needs. The IGBT device in the test valve 600 can also be replaced with an IGCT device or an IEGT device, depending on actual needs. Furthermore, the number of the two components connected in series in the test valve 600 can be adjusted based on actual needs.

[0045] It should be further explained that the types of components connected in series in the first test valve 400 and the second test valve 500 may also include IGBT devices, IGCT devices and IEGT devices. The number of each type of components can be selected according to actual needs.

[0046] Please see Figure 5 , Figure 5 A flow chart of a power cycle test method for a series valve provided in an embodiment of the present invention.

[0047] In one embodiment, in order to more clearly understand the power cycle test circuit of the series valve provided by the present invention, an embodiment of the present invention further provides a power cycle test method of the series valve, the specific process of which is described as follows.

[0048] S1 triggers the opening of the first accompanying test valve and the test valve, when the current in the test valve rises to a set value, the trigger closes the first accompanying test valve;

[0049] S2. When the current duration in the test valve reaches the set value, the second accompanying test valve is triggered to open;

[0050] S3. When the current in the tested valve is less than the set value or equals to 0, the second accompanying test valve and the tested valve are triggered to be closed.

[0051] Through the above implementation process, a cycle of testing can be completed. When S3 is completed, the test can be carried out according to the test parameters of the next cycle.

[0052] In summary, an embodiment of the present invention provides a power cycle test circuit and method for a series valve, including a voltage source, a first auxiliary valve, a second auxiliary valve, a first test valve, a second test valve, a test valve, a load inductor and a coupling inductor; the anode of the first test valve, the cathode of the second auxiliary valve and the anode of the second test valve are all connected to the positive pole of the voltage source; the anode of the first auxiliary valve and the common end of the coupling inductor are both connected to the negative pole of the voltage source; the first end of the load inductor and the cathode of the first auxiliary valve are both connected to the cathode of the first test valve; the anode of the second auxiliary valve and the anode of the test valve are both connected to the second end of the load inductor; the cathode of the test valve is connected to the primary side of the coupling inductor; and the cathode of the second test valve is connected to the secondary side of the coupling inductor. Through the above method, the electrical performance of the series valve can be quickly verified, and the circuit is simpler and the cost is reduced.

[0053] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A power cycle test circuit for a series valve, characterized in that: The device comprises a voltage source, a first auxiliary valve, a second auxiliary valve, a first test valve, a second test valve, a test valve, a load inductor and a coupling inductor; the anode of the first test valve, the cathode of the second auxiliary valve and the anode of the second test valve are all connected to the positive electrode of the voltage source; the anode of the first auxiliary valve and the common end of the coupling inductor are both connected to the negative electrode of the voltage source; the first end of the load inductor and the cathode of the first auxiliary valve are both connected to the cathode of the first test valve; the anode of the second auxiliary valve and the anode of the test valve are both connected to the second end of the load inductor; the cathode of the test valve is connected to the primary side of the coupling inductor; the cathode of the second test valve is connected to the secondary side of the coupling inductor; the first auxiliary valve and the second auxiliary valve form a diode valve string.

2. The power cycle test circuit of the series valve according to claim 1, characterized in that: The first test valve is composed of a component of any type among an IGBT device, an IGCT device and an IEGT device.

3. The power cycle test circuit of the series valve according to claim 2, characterized in that: The second test valve is composed of a component of any type among an IGBT device, an IGCT device and an IEGT device.

4. The power cycle test circuit of the series valve according to claim 1, characterized in that: The first test valve is composed of a plurality of components of the same type among IGBT devices, IGCT devices and IEGT devices connected in series.

5. The power cycle test circuit of the series valve according to claim 4, characterized in that: The second test valve is composed of a plurality of components of the same type among IGBT devices, IGCT devices and IEGT devices connected in series.

6. The power cycle test circuit of the series valve according to any one of claims 2 to 5, characterized in that: The test valve is composed of a component of any type among an IGBT device, an IGCT device and an IEGT device and a thyristor in series.

7. A power cycle test method for a series valve, applied to the power cycle test circuit for a series valve according to any one of claims 1 to 6, characterized in that: include: Triggering to open the first accompanying test valve and the tested valve, and when the current in the tested valve rises to a set value, triggering to close the first accompanying test valve; When the duration of the current in the tested valve reaches a set value, the second accompanying test valve is triggered to open; When the current in the tested valve is less than the set value or equals to 0, the second accompanying test valve and the tested valve are triggered to be closed.

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