A voltage clamping circuit and a high voltage direct current power supply system
By stabilizing the line voltage in the high-voltage DC system through a voltage clamping circuit, the problem of increased safety distance caused by the load-to-ground insulation impedance is solved, thereby improving the flexibility and safety of the system design.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- VERTIV CORP
- Filing Date
- 2025-05-27
- Publication Date
- 2026-07-21
AI Technical Summary
In high-voltage DC systems, the insulation resistance of the load to ground causes neutral voltage deviation, increases safety distance requirements, limits the compact design of the power supply system, and increases cost and difficulty.
A voltage clamping circuit is adopted, including transistors, three-terminal semiconductor devices, resistors and voltage regulators. The voltage is regulated by the voltage regulators, the current is limited by the transistors, and it has overcurrent protection function, reducing the neutral-to-ground voltage range and reducing safety distance requirements.
It effectively stabilizes the neutral voltage, reduces the voltage between the positive and negative poles and ground, improves the system design flexibility and power density, and provides overcurrent protection in case of faults to ensure system safety.
Smart Images
Figure CN224536406U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of energy technology, and in particular to a voltage clamping circuit and a high-voltage DC power supply system. Background Technology
[0002] With the widespread application of High Voltage Direct Current (HVDC) technology, HVDC systems are gradually becoming mainstream in data centers, industrial power supplies, and other high-power applications.
[0003] However, due to the high operating voltage of HVDC, its safety distance requirements are relatively large. Moreover, in HVDC systems, the insulation resistance of the load to ground may cause the neutral voltage to shift, which in turn increases the voltage of the positive and negative terminals to ground, further increasing the safety distance requirements. This not only limits the compact design of the power supply system, but may also increase manufacturing costs and application difficulties.
[0004] Therefore, how to reduce safety distance requirements while ensuring electrical safety has become a key challenge in the design of high-voltage direct current systems. Utility Model Content
[0005] This application provides a voltage clamping circuit and a high-voltage DC power supply system to stabilize the neutral voltage of the high-voltage DC system, avoid large-scale fluctuations in the voltage between its positive and negative poles and ground, and reduce the safety distance requirements of the high-voltage DC power supply system.
[0006] In a first aspect, embodiments of this application provide a voltage clamping circuit, comprising: a transistor, a three-terminal semiconductor device, a first resistor, a second resistor, and at least one voltage regulator, wherein...
[0007] The first terminal of the transistor is connected to the first terminal of the second resistor and the second terminal of the three-terminal semiconductor device, the second terminal of the transistor is connected to the second terminal of the second resistor, and the intermediate node between the second terminal of the transistor and the second terminal of the second resistor is the first terminal of the circuit.
[0008] The third terminal of the transistor is connected to the first terminal of the first resistor and the first terminal of the three-terminal semiconductor device, respectively, and the second terminal of the first resistor is connected to the third terminal of the three-terminal semiconductor device, serving as the second terminal of the circuit.
[0009] The voltage regulator is connected between the second terminal of the transistor and the intermediate node, and / or between the third terminal of the transistor and the target node, wherein the target node is the connection node of the third terminal of the transistor, the first terminal of the first resistor, and the first terminal of the three-terminal semiconductor device.
[0010] When the voltage clamping circuit described above is connected to the circuit at the first and second terminals, the voltage regulator can effectively regulate the voltage, and the transistor can limit the current passing through the voltage regulator, thus providing overcurrent protection. For example, when the voltage clamping circuit is connected to an HVDC system, it can effectively clamp the neutral-to-ground voltage of the HVDC system to a smaller voltage range, thereby reducing the positive and negative voltages to ground, reducing safety distance requirements, and improving the design flexibility and power density of the system.
[0011] In one possible implementation, the voltage regulator includes a plurality of Zener diodes connected in series.
[0012] In one possible implementation, the transistor is a bipolar junction transistor (BJT), with its first terminal being the base, its second terminal being the collector, and its third terminal being the emitter.
[0013] In one possible implementation, the transistor is a metal-oxide-semiconductor field-effect transistor (MOSFET), wherein the first terminal of the MOSFET is the gate, the second terminal is the drain, and the third terminal is the source.
[0014] In one possible implementation, the three-terminal semiconductor device is a transistor, with the first terminal being the base, the second terminal being the collector, and the third terminal being the emitter.
[0015] In one possible implementation, the three-terminal semiconductor device is a MOSFET, wherein the first terminal of the MOSFET is the gate, the second terminal is the drain, and the third terminal is the source.
[0016] In one possible implementation, the three-terminal semiconductor device is a three-terminal adjustable parallel voltage regulator, wherein the first terminal of the three-terminal adjustable parallel voltage regulator is a reference electrode, the second terminal is a cathode, and the third terminal is an anode.
[0017] Secondly, embodiments of this application provide a high-voltage DC power supply system, comprising: a high-voltage DC system and at least one voltage clamping circuit provided in the first aspect of embodiments of this application, wherein...
[0018] The first terminal of the voltage clamping circuit is connected to the neutral line of the high-voltage DC system, and the second terminal is connected to the ground line; and / or
[0019] The first terminal of the voltage clamping circuit is connected to the ground wire, and the second terminal is connected to the neutral wire of the high voltage DC system.
[0020] In the above system, the voltage clamping circuit can effectively clamp the neutral-to-ground voltage of the HVDC system to a smaller voltage range, thereby reducing the positive and negative voltages to ground, reducing safety distance requirements, improving the system's design flexibility and power density, and through overcurrent protection, it can withstand higher voltages when a single-ended short-circuit fault occurs.
[0021] In one possible implementation, the system further includes a first diode connected between a first terminal of the first voltage clamping circuit and the neutral line of the high-voltage DC system, wherein the anode of the first diode is connected to the neutral line of the high-voltage DC system.
[0022] In one possible implementation, the system further includes a second diode connected to a first terminal of the second voltage clamping circuit and grounded, wherein the anode of the second diode is connected to ground. Attached Figure Description
[0023] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0024] Figure 1 This is a schematic diagram of a voltage clamping circuit provided in an embodiment of this application;
[0025] Figure 2 This is a schematic diagram of another voltage clamping circuit provided in an embodiment of this application;
[0026] Figure 3 This is a schematic diagram of another voltage clamping circuit provided in an embodiment of this application;
[0027] Figure 4 This is a schematic diagram of another voltage clamping circuit provided in an embodiment of this application;
[0028] Figure 5 This is a schematic diagram of another voltage clamping circuit provided in an embodiment of this application;
[0029] Figure 6 This is a schematic diagram of a high-voltage power supply system provided in an embodiment of this application. Detailed Implementation
[0030] To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0031] In the description of the embodiments of this application, unless otherwise stated, " / " means "or". For example, A / B can mean A or B. The "and / or" in the text is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in the description of the embodiments of this application, "multiple" means two or more.
[0032] Hereinafter, the terms "first" and "second" are used for descriptive purposes only and should not be construed as implying or suggesting relative importance or implicitly indicating the number of indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature.
[0033] Before introducing the voltage clamping circuit and high-voltage DC power supply system provided in the embodiments of this application, the technical background of the embodiments of this application will be described in detail for ease of understanding.
[0034] With the widespread application of High Voltage Direct Current (HVDC) technology, HVDC systems are gradually becoming mainstream in data centers, industrial power supplies, and other high-power applications.
[0035] However, due to the high operating voltage of HVDC, its safety distance requirements are relatively large. Moreover, in HVDC systems, the insulation resistance of the load to ground may cause the neutral voltage to shift, which in turn increases the voltage of the positive and negative terminals to ground, further increasing the safety distance requirements. This not only limits the compact design of the power supply system, but may also increase manufacturing costs and application difficulties.
[0036] Therefore, how to reduce safety distance requirements while ensuring electrical safety has become a key challenge in the design of high-voltage direct current systems.
[0037] In view of this, embodiments of this application provide a voltage clamping circuit and a high-voltage DC power supply system. When the first and second terminals of the voltage clamping circuit are connected to the circuit, the voltage regulator can effectively regulate the voltage, and the transistor can limit the current through the voltage regulator, providing overcurrent protection. When connected to a high-voltage DC power supply system, the voltage clamping circuit can effectively clamp the neutral-to-ground voltage of the HVDC system to a smaller voltage range, thereby reducing the positive and negative voltages to ground, lowering safety distance requirements, improving system design flexibility and power density, and through the overcurrent protection function, it can withstand higher voltages when a single-ended short-circuit fault occurs.
[0038] It should be noted that the voltage clamping circuit provided in this application embodiment can also be linked with other systems to trigger an alarm or shutdown protection when the current limiting capacity is exceeded, so as to ensure the safe operation of the system.
[0039] After introducing the background technology of the embodiments of this application, the voltage clamping circuit and high-voltage DC power supply system provided by the embodiments of this application will be described in detail below with reference to specific embodiments.
[0040] See Figure 1 As shown, it is a schematic diagram of a voltage clamping circuit provided in an embodiment of this application, including: a transistor 11, a three-terminal semiconductor device 12, a first resistor 13, a second resistor 14, and at least one voltage regulator device 15.
[0041] The first terminal of transistor 11 is connected to the first terminal of second resistor 14 and the second terminal of three-terminal semiconductor device 12 respectively. The second terminal of transistor 11 is connected to the second terminal of second resistor 14. The intermediate node between the second terminal of transistor 11 and the second terminal of second resistor 14 is the first terminal 16 of the circuit.
[0042] The third terminal of transistor 11 is connected to the first terminal of first resistor 13 and the first terminal of three-terminal semiconductor device 12, respectively. The second terminal of first resistor 13 is connected to the third terminal of three-terminal semiconductor device 12, serving as the second terminal 17 of the circuit.
[0043] The voltage regulator 15 is connected between the second terminal of the transistor 11 and the intermediate node, and / or between the third terminal of the transistor 11 and the target node, wherein the target node is the connection node of the third terminal of the transistor, the first terminal of the first resistor, and the first terminal of the three-terminal semiconductor device.
[0044] Figure 1 The voltage regulator 15 shown is connected between the second terminal of transistor 11 and the intermediate node. In other embodiments of this application, such as... Figure 2 As shown, the voltage regulator 15 can also be connected between the third terminal of the transistor 11 and the target node, such as... Figure 3As shown, two voltage regulators 151 and 152 can also be set in the voltage clamping circuit. Voltage regulator 151 is connected between the second terminal of transistor 11 and the intermediate node, and voltage regulator 152 is connected between the third terminal of transistor 11 and the target node.
[0045] In specific implementation, the voltage regulator 15 can be a single voltage regulator diode or multiple voltage regulator diodes connected in series. For ease of description, the following embodiments of this application will use a single voltage regulator diode connected between the second end of transistor 11 and the intermediate node as an example.
[0046] In practice, a transistor can be either a bipolar junction transistor (BJT) or a MOSFET. When a transistor is a BJT, its first terminal is the base, its second terminal is the collector, and its third terminal is the emitter. When a transistor is a MOSFET, its first terminal is the gate, its second terminal is the drain, and its third terminal is the source.
[0047] A three-terminal semiconductor device can be a transistor (or multiple transistors connected in various Darlington configurations as a single transistor), a MOSFET, or a three-terminal adjustable parallel regulator (e.g., TL431). When the three-terminal semiconductor device is a transistor, its first terminal is the base, the second terminal is the collector, and the third terminal is the emitter. When the three-terminal semiconductor device is a MOSFET, its first terminal is the gate, the second terminal is the drain, and the third terminal is the source. When the three-terminal semiconductor device is a three-terminal adjustable parallel regulator, its first terminal is the reference, the second terminal is the cathode, and the third terminal is the anode.
[0048] It should be noted that in practical applications, transistors and three-terminal semiconductor devices can be flexibly selected, and transistors can be NPN or PNP type, and MOSFETs can be N type or P type. This application does not limit these options.
[0049] The following is a brief description of the specific connection structures of transistors and three-terminal semiconductor devices in the embodiments of this application, using specific examples.
[0050] In one example, such as Figure 4As shown in the figures, Figure (A) shows a circuit structure where transistor 41 and three-terminal semiconductor device 42 are both NPN transistors; Figure (B) shows a circuit structure where transistor 43 and three-terminal semiconductor device 44 are both PNP transistors; Figure (C) shows a circuit structure where transistor 45 and three-terminal semiconductor device 46 are both N-type MOSFETs; Figure (D) shows a circuit structure where transistor 47 and three-terminal semiconductor device 48 are both P-type MOSFETs; Figure (E) shows a circuit structure where transistor 51 is an NPN transistor and three-terminal semiconductor device 52 is an N-type MOSFET; Figure (F) shows a circuit structure where transistor 53 is a P-type MOSFET and three-terminal semiconductor device 54 is a PNP transistor; Figure (G) shows a circuit structure where transistor 55 is an N-type MOSFET and three-terminal semiconductor device 56 is an NPN transistor; and Figure (H) shows a circuit structure where transistor 57 is a PNP transistor and three-terminal semiconductor device 58 is a P-type MOSFET.
[0051] In another example, such as Figure 5 As shown, Figure 5 The circuit structure shown is an NPN transistor and a three-terminal semiconductor device is a three-terminal adjustable parallel voltage regulator. Of course, the transistor can also be a PNP transistor, an N-type MOSFET, or a P-type MOSFET.
[0052] The following is combined with Figure 4 Taking the circuit structure (A) as an example, the principle of the voltage clamping circuit provided in the embodiments of this application will be explained.
[0053] In the voltage clamping circuit provided in this embodiment, the first resistor acts as a shunt resistor to detect the current through the Zener diode. Transistor 41 limits the current through the Zener diode. Transistor 42 determines whether it has entered the current-limiting region based on the voltage across the first resistor. Specifically, as the voltage across the first resistor gradually increases, when the voltage approaches the Vbe voltage of transistor 42, transistor 42 begins to conduct, and the collector voltage of transistor 42 is gradually pulled up. As the base voltage of transistor 41 gradually increases, the Vbe voltage of transistor 41 gradually decreases, causing transistor 41 to exit the saturation region. This pulls down the base of transistor 41, allowing it to enter the linear amplification region, thereby limiting the current through the Zener diode. The second resistor provides a pull-up to the base of transistor 41, allowing transistor 41 to reach the set current-limiting point (I0). lim =Vbe / R1, where Vbe is the Vbe voltage of transistor 42 and R1 is the resistance value of the first resistor) operates in the saturation region below this value. The Zener diode is used to stabilize the circuit voltage at the set voltage value.
[0054] When the voltage clamping circuit described above is connected to the circuit via the first and second terminals, the voltage regulator can effectively regulate the voltage, and the transistor can limit the current passing through the voltage regulator, thus providing overcurrent protection.
[0055] Based on the same concept, embodiments of this application provide a high-voltage DC power supply system, such as... Figure 6 As shown, it includes: a high-voltage DC system 61 and at least one voltage clamping circuit provided in an embodiment of this application. Figure 6 The voltage clamping circuit 62 and voltage clamping circuit 63 are shown in the figure.
[0056] It should be noted that in a high-voltage DC power supply system, voltage clamping circuit 62 can be set separately, voltage clamping circuit 63 can be set separately, or both voltage clamping circuit 62 and voltage clamping circuit 63 can be set simultaneously.
[0057] In practice, the first terminal of the voltage clamping circuit 62 is connected to the neutral line of the high-voltage DC system, and the second terminal is connected to the ground line.
[0058] The first terminal of the voltage clamping circuit 63 is connected to the ground wire, and the second terminal is connected to the neutral wire of the high voltage DC system.
[0059] In practical applications, the high-voltage DC power supply system also includes: a first diode, which is connected between the first terminal of the first voltage clamping circuit (i.e., voltage clamping circuit 62) and the neutral line of the high-voltage DC system, with the anode of the first diode connected to the neutral line of the high-voltage DC system; and a second diode, which is connected between the first terminal of the second voltage clamping circuit (i.e., voltage clamping circuit 63) and the ground wire, with the anode of the second diode connected to the ground wire.
[0060] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.
Claims
1. A voltage clamping circuit, characterized by, include: A transistor, a three-terminal semiconductor device, a first resistor, a second resistor, and at least one voltage regulator, wherein, The first terminal of the transistor is connected to the first terminal of the second resistor and the second terminal of the three-terminal semiconductor device, the second terminal of the transistor is connected to the second terminal of the second resistor, and the intermediate node between the second terminal of the transistor and the second terminal of the second resistor is the first terminal of the circuit. The third terminal of the transistor is connected to the first terminal of the first resistor and the first terminal of the three-terminal semiconductor device, respectively, and the second terminal of the first resistor is connected to the third terminal of the three-terminal semiconductor device, serving as the second terminal of the circuit. The voltage regulator is connected between the second terminal of the transistor and the intermediate node, and / or between the third terminal of the transistor and the target node, wherein the target node is the connection node of the third terminal of the transistor, the first terminal of the first resistor, and the first terminal of the three-terminal semiconductor device.
2. The circuit of claim 1, wherein, The voltage regulator includes multiple Zener diodes connected in series.
3. The circuit of claim 1, wherein, The transistor is a bipolar junction transistor (BJT), with its first terminal being the base, its second terminal being the collector, and its third terminal being the emitter.
4. The circuit of claim 1, wherein, The transistor is a metal-oxide-semiconductor field-effect transistor (MOSFET), with the first terminal being the gate, the second terminal being the drain, and the third terminal being the source.
5. The circuit of claim 1, wherein, The three-terminal semiconductor device is a transistor, with the first terminal being the base, the second terminal being the collector, and the third terminal being the emitter.
6. The circuit of claim 1, wherein, The three-terminal semiconductor device is a MOSFET, with the first terminal being the gate, the second terminal being the drain, and the third terminal being the source.
7. The circuit of claim 1, wherein The three-terminal semiconductor device is a three-terminal adjustable parallel voltage regulator. The first terminal of the three-terminal adjustable parallel voltage regulator is the reference electrode, the second terminal is the cathode, and the third terminal is the anode.
8. A high voltage direct current power supply system characterized by, include: The high-voltage DC system and at least one voltage clamping circuit as described in any one of claims 1-7, wherein, The first terminal of the voltage clamping circuit is connected to the neutral line of the high-voltage DC system, and the second terminal is connected to the ground line; and / or The first terminal of the voltage clamping circuit is connected to the ground wire, and the second terminal is connected to the neutral wire of the high voltage DC system.
9. The system of claim 8, wherein, The system further includes a first diode, which is connected between a first terminal of the first voltage clamping circuit and the neutral line of the high voltage DC system, and the anode of the first diode is connected to the neutral line of the high voltage DC system.
10. The system of claim 8, wherein, The system further includes a second diode, which is connected to the ground wire at the first terminal of the second voltage clamping circuit, and the anode of the second diode is connected to the ground wire.