A converter valve cooling system and its control method

Abstract

The present invention relates to a converter valve cooling system and its control method. The cooling system includes two identical converter valve cooling devices. By connecting the valve hall pipelines of the two converter valve cooling devices to each other and physically isolating them using electric switch valves, when one converter valve cooling device needs to be taken out of operation due to a fault, the electric switch valve opens, and the cooling medium of the other converter valve cooling device enters the valve hall pipeline of the faulty cooling device, which can supplement its cooling function. At this time, the converter valve will not lock and can still operate at a certain power, avoiding the converter valve tripping event caused by the fault of a single converter valve cooling device, and ultimately achieving the purpose of improving the reliability of the converter valve cooling system and increasing the availability of the converter valve system.

Description

Technical Field

[0001] The present invention relates to the technical field of DC power transmission, and particularly to a converter valve cooling system and a control method thereof. Background Art

[0002] With the continuous advancement of the construction of the global energy Internet, DC power transmission technology has been increasingly applied in the power transmission field due to its outstanding advantages. As the core equipment in DC power transmission projects, a large amount of heat is generated during the AC-DC conversion process of the converter valve. As the key equipment for transporting the heat of the converter valve, the valve cooling system plays a crucial role in the safe and stable operation of the converter valve. However, according to the statistics of the high-voltage DC professional technical summary report, the number of unplanned outages of the DC system directly caused by the valve cooling system accounts for more than 30% of the total, indicating that the valve cooling equipment has become one of the greatest risks affecting the safe and reliable operation of the DC system.

[0003] In addition, with the rapid development of power semiconductor technology in recent years, the withstand voltage level and transmission capacity of the converter valve have been continuously improved, and the losses during the AC-DC conversion process of the converter valve have also been continuously increasing, thus posing higher requirements for the heat transfer capacity and reliability of the valve cooling system. The traditional one-to-one correspondence between a set of converter valves and a set of valve cooling systems can no longer meet the working requirements of the converter valve.

[0004] To solve the problems of reduced reliability and small heat transfer capacity of a single valve cooling system, the current method is to dissipate heat from a set of converter valves by setting up two completely identical and independent valve cooling systems, and one valve cooling system is responsible for transporting half of the heat generated by the converter valve. However, the following problems still exist in the above method:

[0005] (1) The two valve cooling systems are independent of each other. When a single valve cooling system fails, the converter valve shuts down, and the reliability of the valve cooling system has not been improved.

[0006] (2) When one valve cooling system fails, the other valve cooling system needs to be forced to shut down or operate under no load, and there is no complementary function between them. Summary of the Invention

[0007] Based on the above situation of the prior art, the purpose of the present invention is to provide a converter valve cooling system and a control method thereof. By connecting the valve hall pipelines of the two valve cooling devices to each other and physically isolating them with electric switch valves, the two valve cooling devices can be switched to work complementarily, avoiding the converter valve tripping event caused by the failure of a single valve cooling system, achieving the purpose of improving the reliability of the valve cooling system, and improving the availability of the converter valve system.

[0008] To achieve the above object, according to one aspect of the present invention, a converter valve cooling system is provided, which includes a first converter valve cooling device, a second converter valve cooling device, a converter valve device, a first valve hall pipeline and a second valve hall pipeline; wherein,

[0009] The first converter valve cooling device and the second converter valve cooling device are the same;

[0010] The first converter valve cooling device is connected to one end of the first valve hall pipeline through a first inlet and outlet valve electric switch valve device;

[0011] The second converter valve cooling device is connected to one end of the second valve hall pipeline through a second inlet and outlet valve electric switch valve device;

[0012] The other ends of the first valve hall pipeline and the second valve hall pipeline are connected through an isolation electric switch valve device.

[0013] Furthermore, both the first converter valve cooling device and the second converter valve cooling device include a main circulation pump, a cooler, a deionization device, a voltage stabilizing device, a makeup water tank, a makeup water pump and a nitrogen cylinder.

[0014] Furthermore, the converter valve device includes 2N bridge arms, where N is a natural number and N≥1.

[0015] Furthermore, the first inlet and outlet valve electric switch valve device includes a first inlet valve electric switch valve and a first outlet valve electric switch valve; the second inlet and outlet valve electric switch valve device includes a second inlet valve electric switch valve and a second outlet valve electric switch valve.

[0016] Furthermore, the isolation electric switch valve device includes a first isolation electric switch valve and a second isolation electric switch valve.

[0017] Furthermore, the first valve hall pipeline includes a first inlet valve hall pipeline and a first outlet valve hall pipeline; the second valve hall pipeline includes a second inlet valve hall pipeline and a second outlet valve hall pipeline.

[0018] Furthermore, the first converter valve cooling device is connected to one end of the first inlet valve hall pipeline through the first inlet valve electric switch valve; the first converter valve cooling device is connected to one end of the first outlet valve hall pipeline through the first outlet valve electric switch valve;

[0019] The second converter valve cooling device is connected to one end of the second inlet valve hall pipeline through the second inlet valve electric switch valve; the second converter valve cooling device is connected to one end of the first outlet valve hall pipeline through the second outlet valve electric switch valve.

[0020] Further, the other ends of the first inlet valve hall pipeline and the second inlet valve hall pipeline are connected through a first isolating motorized switch valve; the other ends of the first outlet valve hall pipeline and the second outlet valve hall pipeline are connected through a second isolating motorized switch valve.

[0021] According to the second aspect of the present invention, there is provided a control method for a converter valve cooling system as described in the first aspect of the present invention, comprising the steps of:

[0022] By adjusting the opening and closing of each motorized switch valve in the first inlet and outlet valve motorized switch valve device, the second inlet and outlet valve motorized switch valve device, and the isolating motorized switch valve device, the cooling system is operated in different working modes;

[0023] The working modes include a normal mode, a first converter valve cooling device failure mode, and a second converter valve cooling device failure mode.

[0024] Further, the step of making the cooling system operate in different working modes by adjusting the opening and closing of each motorized switch valve in the first inlet and outlet valve motorized switch valve device, the second inlet and outlet valve motorized switch valve device, and the isolating motorized switch valve device includes:

[0025] Opening the first inlet valve motorized switch valve, the first outlet valve motorized switch valve, the second inlet valve motorized switch valve, and the second outlet valve motorized switch valve, and closing the first isolating motorized switch valve and the second isolating motorized switch valve, so that the system operates in the normal mode;

[0026] Opening the second inlet valve motorized switch valve, the second outlet valve motorized switch valve, the first isolating motorized switch valve, and the second isolating motorized switch valve, and closing the first inlet valve motorized switch valve and the first outlet valve motorized switch valve, so that the system operates in the first converter valve cooling device failure mode;

[0027] Opening the first inlet valve motorized switch valve, the first outlet valve motorized switch valve, the first isolating motorized switch valve, and the second isolating motorized switch valve, and closing the second inlet valve motorized switch valve and the second outlet valve motorized switch valve, so that the system operates in the second converter valve cooling device failure mode.

[0028] In summary, the present invention provides a converter valve cooling system and its control method. The cooling system includes two identical converter valve cooling devices. By connecting the valve hall pipelines of the two converter valve cooling devices to each other and physically isolating them using electric switch valves, when one converter valve cooling device needs to be taken out of service due to a fault, the electric switch valve opens, and the cooling medium of the other converter valve cooling device enters the valve hall pipeline of the faulty cooling device, which can supplement its cooling function. At this time, the converter valve will not lock, and it can still operate at a certain power, avoiding the converter valve tripping event caused by the fault of a single converter valve cooling device, and ultimately achieving the purpose of improving the reliability of the converter valve cooling system and increasing the availability of the converter valve system.

[0029] The present invention has the following beneficial technical effects compared with the prior art:

[0030] (1) Compared with the scheme of one set of converter valve corresponding to one set of valve cooling system, the converter valve cooling system has a complementary function, which can ensure that when one set of converter valve cooling device needs to be taken out of service due to a fault, the other set of converter valve cooling device can be supplemented in time, and the converter valve will not be shut down. It has the characteristics of high reliability, simple structure and convenient operation;

[0031] (2) The physical isolation between the two sets of converter valve cooling devices adopts an electric switch valve design, which has a status monitoring function. When a fault occurs, it can send alarm information in time to remind the operation and maintenance personnel to deal with it in time;

[0032] (3) The complementary switching between the two sets of converter valve cooling devices adopts remote control, and there is no need for manual operation by personnel, providing conditions for the continuous operation of the converter valve device. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 is a block diagram of the structure of the converter valve cooling system of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] To make the purpose, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below in conjunction with the specific embodiments and with reference to the accompanying drawings. It should be understood that these descriptions are exemplary and not intended to limit the scope of the present invention. In addition, in the following description, the descriptions of well-known structures and technologies are omitted to avoid unnecessarily confusing the concepts of the present invention.

[0035] The technical solutions of the present invention will be described in detail below in conjunction with the accompanying drawings. According to an embodiment of the present invention, a converter valve cooling system is provided, and the block diagram of the structure of the system is as Figure 1As shown in the figure, it includes a first converter valve cooling device, a second converter valve cooling device, a converter valve device 8, a first valve hall pipeline, and a second valve hall pipeline. Among them, the first converter valve cooling device and the second converter valve cooling device are the same, and both include a main circulation pump 1, an outdoor cooler 2, a deionization device 3, a voltage stabilizing device 4, a water replenishing tank 6, a water replenishing pump 5, and a nitrogen cylinder 7. The converter valve device 8 includes 2N bridge arms, where N is a natural number and N≥1. In this embodiment, the converter valve device 8 includes 6 bridge arms, which are divided into upper bridge arms, namely bridge arm 1, bridge arm 2, and bridge arm 3, and lower bridge arms, namely bridge arm 4, bridge arm 5, and bridge arm 6.

[0036] A large amount of heat is generated during the AC-DC conversion of the converter valve device 8, and the heat is transferred to the cooling water through heat conduction. Among them, the cooling water of the upper bridge arms, namely bridge arm 1-3, enters the outdoor cooler 2 for cooling under the drive of the main circulation pump 1 of the first converter valve cooling device. After the cooling water is cooled, it is sent back to the converter valve device 8 by the main circulation pump 1, and this cycle repeats. The cooling water of the lower bridge arms, namely bridge arm 4-6, enters the outdoor cooler 2 for cooling under the drive of the main circulation pump 1 of the second converter valve cooling device. After the cooling water is cooled, it is sent back to the converter valve device 8 by the main circulation pump 1, and this cycle repeats. The converter valve cooling device is also provided with a deionization device 3, a voltage stabilizing device 4, and a water replenishing tank 6 to ensure the normal and stable operation of the converter valve cooling device.

[0037] The first converter valve cooling device is connected to one end of the first valve hall pipeline through the first inlet and outlet valve electric switch valve device; the second converter valve cooling device is connected to one end of the second valve hall pipeline through the second inlet and outlet valve electric switch valve device; the other ends of the first valve hall pipeline and the second valve hall pipeline are connected through the isolation electric switch valve device. Among them, the first inlet and outlet valve electric switch valve device includes a first inlet valve electric switch valve 9 and a first outlet valve electric switch valve 10; the second inlet and outlet valve electric switch valve device includes a second inlet valve electric switch valve 13 and a second outlet valve electric switch valve 14; the isolation electric switch valve device includes a first isolation electric switch valve 11 and a second isolation electric switch valve 12. The first valve hall pipeline includes a first inlet valve hall pipeline and a first outlet valve hall pipeline; the second valve hall pipeline includes a second inlet valve hall pipeline and a second outlet valve hall pipeline. The first converter valve cooling device is connected to one end of the first inlet valve hall pipeline through the first inlet valve electric switch valve 9; the first converter valve cooling device is connected to one end of the first outlet valve hall pipeline through the first outlet valve electric switch valve 10; the second converter valve cooling device is connected to one end of the second inlet valve hall pipeline through the second inlet valve electric switch valve 13; the second converter valve cooling device is connected to one end of the first outlet valve hall pipeline through the second outlet valve electric switch valve 14. The other ends of the first inlet valve hall pipeline and the second inlet valve hall pipeline are connected through the first isolation electric switch valve 11; the other ends of the first outlet valve hall pipeline and the second outlet valve hall pipeline are connected through the second isolation electric switch valve 12. The converter valve cooling system provided in this embodiment can, according to the states of the two sets of converter valve cooling devices, quickly and flexibly switch between the normal mode, the first converter valve cooling device failure mode, and the second converter valve cooling device failure mode by adjusting each electric switch valve 9-14, and can ensure that the converter valve device can still operate at a certain power.

[0038] According to the second embodiment of the present invention, a control method for a converter valve cooling system as described in the first embodiment of the present invention is provided, including the following steps:

[0039] By adjusting the opening and closing of each electric switch valve in the first inlet and outlet valve electric switch valve device, the second inlet and outlet valve electric switch valve device, and the isolation electric switch valve device, the cooling system is operated in different working modes;

[0040] The working modes include a normal mode, a first converter valve cooling device failure mode, and a second converter valve cooling device failure mode.

[0041] Further, the step of operating the cooling system in different working modes by adjusting the opening and closing of each electric switch valve in the first inlet and outlet valve electric switch valve device, the second inlet and outlet valve electric switch valve device, and the isolation electric switch valve device includes:

[0042] Open the first inlet valve electric switch valve 9, the first outlet valve electric switch valve 10, the second inlet valve electric switch valve 13 and the second outlet valve electric switch valve 14, and close the first isolation electric switch valve 11 and the second isolation electric switch valve 12, so that the system operates in the normal mode. When both the first converter valve cooling device and the second converter valve cooling device are normal, the system operates in the normal mode. At this time, the two sets of converter valve cooling devices are in a completely independent state, and each set of converter valve cooling devices exerts the maximum heat exchange capacity to dissipate heat from the converter valve device, ensuring that the converter valve device can be fully cooled under various working conditions.

[0043] Open the second inlet valve electric switch valve 13, the second outlet valve electric switch valve 14, the first isolation electric switch valve 11 and the second isolation electric switch valve 12, and close the first inlet valve electric switch valve 9 and the first outlet valve electric switch valve 10, so that the system operates in the first converter valve cooling device failure mode. When the first converter valve cooling device fails and needs to be shut down for maintenance, at this time, the cooling water of the second converter valve cooling device enters the upper bridge arm 1-3 through the valve hall pipeline connecting the two sets of converter valve cooling devices to cool the upper bridge arm 1-3, so that the converter valve device can still maintain a certain power and operate, improving the reliability of the valve cooling system and the availability of the converter valve.

[0044] Open the first inlet valve electric switch valve 9, the first outlet valve electric switch valve 10, the first isolation electric switch valve 11 and the second isolation electric switch valve 12, and close the second inlet valve electric switch valve 13 and the second outlet valve electric switch valve 14, so that the system operates in the second converter valve cooling device failure mode. When the second converter valve cooling device fails and needs to be shut down for maintenance, at this time, the cooling water of the first converter valve cooling device enters the lower bridge arm 4-6 through the valve hall pipeline connecting the two sets of converter valve cooling devices to cool the lower bridge arm 4-6, so that the converter valve device can still maintain a certain power and operate, improving the reliability of the valve cooling system and the availability of the converter valve.

[0045] In summary, the present invention relates to a converter valve cooling system and its control method. The cooling system includes two identical converter valve cooling devices. By connecting the valve hall pipelines of the two sets of converter valve cooling devices to each other and physically isolating them using electric switch valves, when one set of converter valve cooling devices needs to be taken out of operation due to a failure, the electric switch valve opens, and the cooling medium of the other set of converter valve cooling devices enters the valve hall pipeline of the failed cooling device, which can supplement its cooling function. At this time, the converter valve will not be blocked and can still maintain a certain power operation, avoiding the converter valve tripping event caused by the failure of a single set of converter valve cooling devices, and ultimately achieving the purpose of improving the reliability of the converter valve cooling system and the availability of the converter valve system.

[0046] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0047] The present invention is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to embodiments of the present invention. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, as well as the combination of flows and / or blocks in the flowcharts and / or block diagrams, can be realized by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing devices generate means for realizing the functions specified in Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0048] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, such that the instructions stored in the computer-readable memory generate a manufactured article including instruction means that realize the functions specified in Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0049] These computer program instructions can also be loaded onto a computer or other programmable data processing device, such that a series of operation steps are executed on the computer or other programmable device to generate a computer-implemented process. Thus, the instructions executed on the computer or other programmable device provide steps for realizing the functions specified in Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the scope of its protection. Although the present invention has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that after reading the present invention, various changes, modifications, or equivalent substitutions can still be made to the specific implementation manners of the invention. However, these changes, modifications, or equivalent substitutions are all within the scope of the claims of the invention pending approval.

Claims

1. A control method for a converter valve cooling system, characterized in that, the converter valve cooling system includes a first converter valve cooling device, a second converter valve cooling device, a converter valve device, a first valve hall pipeline and a second valve hall pipeline; wherein, the first converter valve cooling device and the second converter valve cooling device are the same; the first converter valve cooling device is connected to one end of the first valve hall pipeline through a first inlet and outlet valve electric switch valve device; the second converter valve cooling device is connected to one end of the second valve hall pipeline through a second inlet and outlet valve electric switch valve device; the other ends of the first valve hall pipeline and the second valve hall pipeline are connected through an isolation electric switch valve device; the control method includes: by adjusting the opening and closing of each electric switch valve in the first inlet and outlet valve electric switch valve device, the second inlet and outlet valve electric switch valve device, and the isolation electric switch valve device, the cooling system operates in different working modes: Opening the first inlet valve electric switch valve, the first outlet valve electric switch valve, the second inlet valve electric switch valve, and the second outlet valve electric switch valve, and closing the first isolation electric switch valve and the second isolation electric switch valve, so that the system operates in the normal mode; Opening the second inlet valve electric switch valve, the second outlet valve electric switch valve, the first isolation electric switch valve, and the second isolation electric switch valve, and closing the first inlet valve electric switch valve and the first outlet valve electric switch valve, so that the system operates in the first converter valve cooling device failure mode; Opening the first inlet valve electric switch valve, the first outlet valve electric switch valve, the first isolation electric switch valve, and the second isolation electric switch valve, and closing the second inlet valve electric switch valve and the second outlet valve electric switch valve, so that the system operates in the second converter valve cooling device failure mode.

2. The method according to claim 1, characterized in that, both the first converter valve cooling device and the second converter valve cooling device include a main circulation pump, a cooler, a deionization device, a voltage stabilizing device, a makeup water tank, a makeup water pump, and a nitrogen cylinder.

3. The method according to claim 2, characterized in that, the converter valve device includes 2N bridge arms, where N is a natural number and N≥1.

4. The method according to claim 3, characterized in that, the first inlet and outlet valve electric switch valve device includes a first inlet valve electric switch valve and a first outlet valve electric switch valve; the second inlet and outlet valve electric switch valve device includes a second inlet valve electric switch valve and a second outlet valve electric switch valve.

5. The method according to claim 4, characterized in that, the isolation electric switch valve device includes a first isolation electric switch valve and a second isolation electric switch valve.

6. The method according to claim 5, characterized in that, the first valve hall pipeline includes a first inlet valve hall pipeline and a first outlet valve hall pipeline; the second valve hall pipeline includes a second inlet valve hall pipeline and a second outlet valve hall pipeline.

7. The method according to claim 6, characterized in that, the first converter valve cooling device is connected to one end of the first inlet valve hall pipeline through the first inlet valve electric switch valve; the first converter valve cooling device is connected to one end of the first outlet valve hall pipeline through the first outlet valve electric switch valve; The second converter valve cooling device is connected to one end of the second inlet valve hall pipeline through the second inlet valve electric switch valve; the second converter valve cooling device is connected to one end of the first outlet valve hall pipeline through the second outlet valve electric switch valve.

8. According to the method described in claim 7, characterized in that the other ends of the first inlet valve hall pipeline and the second inlet valve hall pipeline are connected through the first isolation electric switch valve; the other ends of the first outlet valve hall pipeline and the second outlet valve hall pipeline are connected through the second isolation electric switch valve.

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