High-voltage capacitor power taking circuit and high-voltage capacitor power taking protection control method
By using a high-voltage capacitor power supply circuit and protection control methods, the voltage threshold is monitored and the isolation transformer is controlled in conjunction with the circuit, thus solving the problem of overvoltage damage to the isolation transformer and achieving high-voltage protection and stable output.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SOUTHERN POWER GRID DIGITAL GRID RESEARCH INSTITUTE CO LTD
- Filing Date
- 2022-10-26
- Publication Date
- 2026-07-31
AI Technical Summary
When drawing power from high-voltage capacitors, the isolation transformer is prone to overvoltage damage, and traditional power drawing methods have problems such as large size, high installation and maintenance costs, and high explosion rate.
A high-voltage capacitor power supply circuit is adopted. Through the linkage control of the high-voltage protection module and the low-voltage sampling capacitor, the voltage threshold is monitored, and the primary side of the isolation transformer is connected or shorted to protect the isolation transformer and avoid overvoltage damage.
It effectively protects the isolation transformer, prevents overvoltage damage, improves output power stability, reduces operation and maintenance costs, and reduces the risk of failure.
Smart Images
Figure CN116073328B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of high-voltage power extraction technology, and in particular to a high-voltage capacitor power extraction circuit, a high-voltage capacitor power extraction protection and control method, a high-voltage protection and control module, and a power system. Background Technology
[0002] Voltage transformer (VT) power supply is a common method in power systems. Its principle is simple: it directly converts high voltage to low voltage to power the transformer (FTU). Its advantages include high power output. However, due to its large size, high installation and maintenance costs, and high explosion rate, it has consistently been a major point of failure in distribution networks. Therefore, new power supply methods have emerged to overcome the disadvantages of VT power supply. One such method is high-voltage capacitor power supply (also known as CL power supply). However, high-voltage capacitor power supply frequently leads to overvoltage damage to the isolation transformer. Summary of the Invention
[0003] Therefore, it is necessary to provide a high-voltage capacitor power extraction circuit, a high-voltage capacitor power extraction protection and control method, a high-voltage protection and control module, and a power system to address the above-mentioned technical problems.
[0004] This application provides a high-voltage capacitor power extraction circuit, the circuit comprising:
[0005] A high-voltage capacitor, the first terminal of which is used to connect to a high-voltage power supply;
[0006] A high-voltage protection module, wherein the first terminal of the high-voltage protection module is connected to the second terminal of the high-voltage capacitor, and the high-voltage protection module is connected in parallel with the primary side of the isolation transformer;
[0007] A low-voltage sampling capacitor, the first terminal of which is connected to the second terminal of the high-voltage protection module, and the second terminal of which is grounded;
[0008] A high-voltage protection control module, wherein a first terminal of the high-voltage protection control module is connected to a first terminal of the low-voltage sampling capacitor, a second terminal of the high-voltage protection control module is connected to a second terminal of the low-voltage sampling capacitor, and a third terminal of the high-voltage protection module is connected to a third terminal of the high-voltage protection module.
[0009] When the high-voltage protection control module detects that the voltage across the low-voltage sampling capacitor exceeds a set threshold, it controls the high-voltage protection module to turn on.
[0010] In one embodiment, the high-voltage capacitor is a CL capacitor.
[0011] In one embodiment, the low-voltage sampling capacitor is a CL capacitor.
[0012] In one embodiment, the secondary side of the isolation transformer is connected to the rectifier module.
[0013] This application provides a protection and control method for high-voltage capacitor power supply, applied to a high-voltage protection and control module, the method comprising:
[0014] Monitor the voltage across the low-voltage sampling capacitor;
[0015] When the voltage across the low-voltage sampling capacitor does not exceed the set threshold, the high-voltage protection module is controlled to not conduct, so that the current flows from the high-voltage power supply to the high-voltage capacitor, then flows through the high-voltage capacitor into the primary side of the isolation transformer, then through the primary side of the isolation transformer into the low-voltage sampling capacitor, and then through the low-voltage sampling capacitor into the grounding point.
[0016] When the voltage across the low-voltage sampling capacitor exceeds a set threshold, the high-voltage protection module is activated to short-circuit the primary side of the isolation transformer.
[0017] In one embodiment, the high-voltage capacitor is a CL capacitor.
[0018] In one embodiment, the low-voltage sampling capacitor is a CL capacitor.
[0019] In one embodiment, the secondary side of the isolation transformer is connected to the rectifier module.
[0020] This application provides a high-voltage protection control module, including:
[0021] The voltage monitoring unit is used to monitor the voltage across the low-voltage sampling capacitor.
[0022] The conduction control unit is used to control the high-voltage protection module to not conduct when the voltage across the low-voltage sampling capacitor does not exceed a set threshold, so that the current flows from the high-voltage power supply to the high-voltage capacitor, then through the high-voltage capacitor into the primary side of the isolation transformer, then through the primary side of the isolation transformer into the low-voltage sampling capacitor, and finally through the low-voltage sampling capacitor into the grounding point; when the high-voltage protection module is on, the primary side of the isolation transformer is short-circuited.
[0023] The conduction control unit is also used to control the high-voltage protection module to conduct when the voltage across the low-voltage sampling capacitor exceeds a set threshold, so that the primary side of the isolation transformer is short-circuited.
[0024] This application provides a power system, which includes a high-voltage capacitor power extraction circuit as follows:
[0025] A high-voltage capacitor, the first terminal of which is used to connect to a high-voltage power supply;
[0026] A high-voltage protection module, wherein the first terminal of the high-voltage protection module is connected to the second terminal of the high-voltage capacitor, and the high-voltage protection module is connected in parallel with the primary side of the isolation transformer;
[0027] A low-voltage sampling capacitor, the first terminal of which is connected to the second terminal of the high-voltage protection module, and the second terminal of which is grounded;
[0028] A high-voltage protection control module, wherein a first terminal of the high-voltage protection control module is connected to a first terminal of the low-voltage sampling capacitor, a second terminal of the high-voltage protection control module is connected to a second terminal of the low-voltage sampling capacitor, and a third terminal of the high-voltage protection module is connected to a third terminal of the high-voltage protection module.
[0029] When the high-voltage protection control module detects that the voltage across the low-voltage sampling capacitor exceeds a set threshold, it controls the high-voltage protection module to turn on.
[0030] In this application, the first terminal of the high-voltage capacitor is connected to the high-voltage power supply, the first terminal of the high-voltage protection module is connected to the second terminal of the high-voltage capacitor, and the high-voltage protection module is connected in parallel with the primary side of the isolation transformer. The first terminal of the low-voltage sampling capacitor is connected to the second terminal of the high-voltage protection module, and the second terminal of the low-voltage sampling capacitor is grounded. The first terminal of the high-voltage protection control module is connected to the first terminal of the low-voltage sampling capacitor, the second terminal of the high-voltage protection control module is connected to the second terminal of the low-voltage sampling capacitor, and the third terminal of the high-voltage protection control module is connected to the third terminal of the high-voltage protection module. When the high-voltage protection control module detects that the voltage across the low-voltage sampling capacitor exceeds a set threshold, it controls the high-voltage protection module to conduct, so that the primary side of the isolation transformer is short-circuited, thereby protecting the isolation transformer itself and the devices on the secondary side from overvoltage damage. Attached Figure Description
[0031] Figure 1 This is a circuit diagram for drawing power from a high-voltage capacitor in one embodiment;
[0032] Figure 2 This is a flowchart illustrating a protection control method for high-voltage capacitor power extraction in one embodiment.
[0033] Figure 3 This is a structural block diagram of a high-voltage protection control module in one embodiment. Detailed Implementation
[0034] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.
[0035] In this application, the reference to "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this application can be combined with other embodiments.
[0036] This application provides a high-voltage capacitor power extraction circuit, such as... Figure 1 As shown, the circuit includes: a high-voltage capacitor 2 (which can be denoted as CH), a high-voltage protection module 3 (which can be denoted as K1), a low-voltage sampling capacitor 4 (which can be denoted as CL), and a high-voltage protection control module 5 (which can be denoted as RY1).
[0037] Among them, the first end of the high voltage capacitor 2 is used to connect to the high voltage power supply 1 (which can be denoted as HV), the first end of the high voltage protection module 3 is connected to the second end of the high voltage capacitor 2, and the high voltage protection module 3 is connected in parallel with the primary side of the isolation transformer 7 (which can be denoted as TR1); the first end of the low voltage sampling capacitor 4 is connected to the second end of the high voltage protection module 3, and the second end of the low voltage sampling capacitor 4 is connected to the grounding point 6 for grounding.
[0038] The first terminal of the high-voltage protection control module 5 is connected to the first terminal of the low-voltage sampling capacitor 4, the second terminal of the high-voltage protection control module 5 is connected to the second terminal of the low-voltage sampling capacitor 4, and the third terminal of the high-voltage protection control module 5 is connected to the third terminal of the high-voltage protection module 3. When the high-voltage protection control module 5 detects that the voltage across the low-voltage sampling capacitor 4 exceeds a set threshold, it controls the high-voltage protection module 3 to conduct.
[0039] After the high-voltage protection module 3 is turned on, the primary side of the isolation transformer 7 is short-circuited, thereby protecting the isolation transformer itself and the secondary side components from overvoltage damage.
[0040] The high-voltage capacitor power supply circuit provided in this application uses CL (Clearing Capacitor) power supply, avoiding the problem of PT (Potentially Transformer) explosion due to secondary short circuits, and avoiding ferroresonance problems that may be caused by single-phase faults. Furthermore, compared to CT (Cross-Circuit Transformer) power supply, the output power is more stable and less affected by weather conditions, with minimal difference in output power on cloudy, rainy, and sunny days. The high-voltage capacitor power supply circuit provided in this application limits the input voltage of the primary side of the isolation transformer 7 when a high-voltage power supply is input, improving the accuracy of high-voltage protection control in the CL capacitor power supply circuit. Moreover, this application solves the problem of overvoltage damage to the isolation transformer 7, which frequently occurs in CL capacitor power supply circuits, through the coordinated control of the high-voltage protection module 3, the low-voltage sampling capacitor 4, and the high-voltage protection control module 5.
[0041] Furthermore, the aforementioned high-voltage capacitor 2 can be a CL capacitor.
[0042] Furthermore, the aforementioned low-voltage sampling capacitor 4 can be a CL capacitor.
[0043] Furthermore, the secondary side of the isolation transformer 7 is connected to the rectifier module 8 (which can be referred to as DR1). Through the processing of the rectifier module 8, the AC power can be converted into DC power.
[0044] Furthermore, since the current in the entire circuit from high-voltage power supply 1 to grounding point 6 is determined by the size of high-voltage capacitor 2 and low-voltage sampling capacitor 4, the voltage level of high-voltage power supply 1, and the frequency of high-voltage power supply, and since the frequency of high-voltage power supply is fixed at 50Hz during circuit operation, and the capacitance of high-voltage capacitor 1 remains constant, the magnitude of the current is determined by the size of high-voltage power supply 1. Because the capacitance of low-voltage sampling capacitor 4 is fixed, the larger the current flowing through the entire circuit, the larger the voltage across low-voltage sampling capacitor 4 will be. When the voltage across low-voltage sampling capacitor 4 reaches a set threshold, high-voltage protection control module 5 controls high-voltage module 3 to conduct, forming a short circuit on the primary side of isolation transformer 7, thereby protecting isolation transformer 7 from high-voltage damage.
[0045] Furthermore, through the cooperation of the high-voltage protection module 3, the low-voltage sampling capacitor 4, and the high-voltage protection control module 5, overvoltage damage to the isolation transformer 7 can be avoided. The cooperation of the high-voltage capacitor 2 and the low-voltage sampling capacitor 4 can accurately obtain the magnitude of the high-voltage power supply 1, thereby providing more precise protection for the isolation transformer 7.
[0046] This application provides a protection and control method for high-voltage capacitor power extraction, applied to high-voltage protection and control module 5, such as... Figure 2 As shown, the method may include the following steps:
[0047] Step S201: Monitor the voltage across the low-voltage sampling capacitor 4;
[0048] Step S202: When the voltage across the low-voltage sampling capacitor 4 does not exceed the set threshold, the high-voltage protection module 3 is controlled not to conduct, so that the current flows from the high-voltage power supply 1 to the high-voltage capacitor 2, then flows through the high-voltage capacitor 2 into the primary side of the isolation transformer 7, then flows through the primary side of the isolation transformer 7 into the low-voltage sampling capacitor 4, and then flows through the low-voltage sampling capacitor 4 into the grounding point 6.
[0049] Step S203: When the voltage across the low-voltage sampling capacitor 4 exceeds a set threshold, the high-voltage protection module 3 is turned on to short-circuit the primary side of the isolation transformer 7.
[0050] When the primary side of the aforementioned isolation transformer 7 is short-circuited, the isolation transformer itself and the components on the secondary side are protected from overvoltage damage. Furthermore, when a high-voltage power supply is input, the input voltage on the primary side of the isolation transformer 7 is limited, improving the accuracy of high-voltage protection control in the CL capacitor power supply circuit. Moreover, this application solves the problem of overvoltage damage to the isolation transformer 7, which frequently occurs in the CL capacitor power supply circuit, through the coordinated control of three modules: the high-voltage protection module 3, the low-voltage sampling capacitor 4, and the high-voltage protection control module 5.
[0051] Furthermore, the aforementioned high-voltage capacitor 2 can be a CL capacitor.
[0052] Furthermore, the aforementioned low-voltage sampling capacitor 4 can be a CL capacitor.
[0053] Furthermore, the secondary side of the isolation transformer 7 is connected to the rectifier module 8, and through the processing of the rectifier module 8, the alternating current can be converted into direct current.
[0054] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.
[0055] This application provides a high-voltage protection control module, such as... Figure 3 As shown, the high-voltage protection control module includes:
[0056] Voltage monitoring unit 301 is used to monitor the voltage across the low-voltage sampling capacitor 4;
[0057] The conduction control unit 302 is used to control the high voltage protection module 3 to not conduct when the voltage across the low voltage sampling capacitor 4 does not exceed a set threshold, so that the current flows from the high voltage power supply 1 to the high voltage capacitor 2, then flows through the high voltage capacitor 2 into the primary side of the isolation transformer 7, then flows through the primary side of the isolation transformer 7 into the low voltage sampling capacitor 4, and then flows through the low voltage sampling capacitor 4 into the grounding point 6.
[0058] The conduction control unit 302 is also used to control the high voltage protection module 3 to conduct when the voltage across the low voltage sampling capacitor 4 exceeds a set threshold, so that the primary side of the isolation transformer 7 is short-circuited.
[0059] When the primary side of the aforementioned isolation transformer 7 is short-circuited, the isolation transformer itself and the components on the secondary side are protected from overvoltage damage. Furthermore, when a high-voltage power supply is input, the input voltage on the primary side of the isolation transformer 7 is limited, improving the accuracy of high-voltage protection control in the CL capacitor power supply circuit. Moreover, this application solves the problem of overvoltage damage to the isolation transformer 7, which frequently occurs in the CL capacitor power supply circuit, through the coordinated control of three modules: the high-voltage protection module 3, the low-voltage sampling capacitor 4, and the high-voltage protection control module 5.
[0060] Furthermore, the aforementioned high-voltage capacitor 2 can be a CL capacitor.
[0061] Furthermore, the aforementioned low-voltage sampling capacitor 4 can be a CL capacitor.
[0062] Furthermore, the secondary side of the isolation transformer 7 is connected to the rectifier module 8, and through the processing of the rectifier module 8, the alternating current can be converted into direct current.
[0063] This application provides a power system including the above-mentioned high-voltage capacitor power supply protection circuit, which includes: a high-voltage capacitor 2, a high-voltage protection module 3, a low-voltage sampling capacitor 4, and a high-voltage protection control module 5.
[0064] Among them, the first end of the high voltage capacitor 2 is used to connect to the high voltage power supply 1, the first end of the high voltage protection module 3 is connected to the second end of the high voltage capacitor 2, and the high voltage protection module 3 is connected in parallel with the primary side of the isolation transformer 7; the first end of the low voltage sampling capacitor 4 is connected to the second end of the high voltage protection module 3, and the second end of the low voltage sampling capacitor 4 is connected to the grounding point 6 for grounding.
[0065] The first terminal of the high-voltage protection control module 5 is connected to the first terminal of the low-voltage sampling capacitor 4, the second terminal of the high-voltage protection control module 5 is connected to the second terminal of the low-voltage sampling capacitor 4, and the third terminal of the high-voltage protection control module 5 is connected to the third terminal of the high-voltage protection module 3. When the high-voltage protection control module 5 detects that the voltage across the low-voltage sampling capacitor 4 exceeds a set threshold, it controls the high-voltage protection module 3 to conduct.
[0066] After the high-voltage protection module 3 is turned on, the primary side of the isolation transformer 7 is short-circuited, thereby protecting the isolation transformer itself and the secondary side components from overvoltage damage.
[0067] When the primary side of the aforementioned isolation transformer 7 is short-circuited, the isolation transformer itself and the components on the secondary side are protected from overvoltage damage. Furthermore, when a high-voltage power supply is input, the input voltage on the primary side of the isolation transformer 7 is limited, improving the accuracy of high-voltage protection control in the CL capacitor power supply circuit. Moreover, this application solves the problem of overvoltage damage to the isolation transformer 7, which frequently occurs in the CL capacitor power supply circuit, through the coordinated control of three modules: the high-voltage protection module 3, the low-voltage sampling capacitor 4, and the high-voltage protection control module 5.
[0068] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, or optical storage, etc. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc.
[0069] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0070] The above embodiments are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.
Claims
1. A high-voltage capacitor power extraction circuit, characterized in that, include: A high-voltage capacitor, the first terminal of which is used to connect to a high-voltage power supply; Isolation transformer; A high-voltage protection module, wherein the first terminal of the high-voltage protection module is connected to the second terminal of the high-voltage capacitor, and the high-voltage protection module is connected in parallel with the primary side of the isolation transformer; A low-voltage sampling capacitor, the first terminal of which is connected to the second terminal of the high-voltage protection module, and the second terminal of which is grounded; A high-voltage protection control module, wherein a first terminal of the high-voltage protection control module is connected to a first terminal of the low-voltage sampling capacitor, a second terminal of the high-voltage protection control module is connected to a second terminal of the low-voltage sampling capacitor, and a third terminal of the high-voltage protection module is connected to a third terminal of the high-voltage protection module. The high-voltage protection control module includes a voltage monitoring unit and a conduction control unit. The voltage monitoring unit is used to monitor the voltage across the low-voltage sampling capacitor. The conduction control unit is used to control the high voltage protection module to not conduct when the voltage across the low voltage sampling capacitor does not exceed a set threshold, so that the current flows from the high voltage power supply to the high voltage capacitor, then flows through the high voltage capacitor into the primary side of the isolation transformer, then into the low voltage sampling capacitor, and finally into the grounding point. When the high-voltage protection module is turned on, the primary side of the isolation transformer is short-circuited; The conduction control unit is also used to control the high-voltage protection module to conduct when the voltage across the low-voltage sampling capacitor exceeds a set threshold, so that the primary side of the isolation transformer is short-circuited.
2. The circuit of claim 1, wherein, The high-voltage capacitor is a CL capacitor.
3. The circuit of claim 1, wherein, The low-voltage sampling capacitor is a CL capacitor.
4. The circuit of claim 1, wherein, The secondary side of the isolation transformer is connected to the rectifier module.
5. A protection control method for high-voltage capacitor power taking, characterized by, The method, applied to a high-voltage protection control module in a high-voltage capacitor power supply circuit as described in any one of claims 1 to 4, comprises: Monitor the voltage across the low-voltage sampling capacitor; When the voltage across the low-voltage sampling capacitor does not exceed the set threshold, the high-voltage protection module is controlled to not conduct, so that the current flows from the high-voltage power supply to the high-voltage capacitor, then flows through the high-voltage capacitor into the primary side of the isolation transformer, then through the primary side of the isolation transformer into the low-voltage sampling capacitor, and finally through the low-voltage sampling capacitor into the grounding point. When the voltage across the low-voltage sampling capacitor exceeds a set threshold, the high-voltage protection module is activated to short-circuit the primary side of the isolation transformer.
6. The method of claim 5, wherein, The high-voltage capacitor is a CL capacitor.
7. The method of claim 5, wherein, The low-voltage sampling capacitor is a CL capacitor.
8. The method according to claim 5, characterized in that, The secondary side of the isolation transformer is connected to the rectifier module.
9. An electric power system, characterized in that, Includes the high-voltage capacitor power supply circuit as described in any one of claims 1 to 4.