An overvoltage protection system and an overvoltage protection method

Abstract

This invention provides an overvoltage protection system and method. The overvoltage protection system includes multiple loads, with an overvoltage protection module connected in parallel to the input of each load. Each overvoltage protection module includes a first protection unit, a second protection unit, and a control unit. The first and second protection units are connected in parallel with their respective loads. The control unit is connected to both the first and second protection units and is also connected in parallel to the main circuit of the corresponding load. The first protection unit is used to bypass the corresponding load. The second protection unit is used to discharge energy. After the second protection unit discharges energy, the control unit controls the first protection unit to bypass the corresponding load. The overvoltage protection system and method provided by this invention improve the reliability of the system.

Description

Technical Field

[0001] This invention relates to the field of electronic circuit technology, and more specifically to an overvoltage protection system and overvoltage protection method. Background Technology

[0002] In marine power transmission systems, power supply stability is like the lifeline of the system, directly affecting the service life and overall reliability of the load equipment.

[0003] In actual operation, marine power transmission systems are prone to abnormal voltage increases due to significant differences in load characteristics, dynamic fluctuations in power output, and unpredictable marine environmental disturbances. Rapid voltage changes not only significantly affect equipment performance but can also cause permanent damage to core components, leading to decreased system reliability. Existing technologies often employ fixed threshold triggering mechanisms for overvoltage protection, which offer advantages such as simple structure, rapid response, and low cost. However, as marine power transmission systems become increasingly complex and load types more diverse, the rigid protection logic of existing fixed threshold triggering technologies is incompatible with the dynamic complexity, load diversity, and overall interconnectivity of actual system operation, thus reducing the reliability of loads in marine power transmission systems. Summary of the Invention

[0004] To address the problems in the prior art, embodiments of the present invention provide an overvoltage protection system and overvoltage protection method, which can at least partially solve the problems existing in the prior art.

[0005] In a first aspect, the present invention proposes an overvoltage protection system, comprising multiple loads, wherein an overvoltage protection module is connected in parallel to the input terminal of each load, wherein: Each overvoltage protection module includes a first protection unit, a second protection unit, and a control unit. The first protection unit and the second protection unit are connected in parallel with the corresponding load. The control unit is connected to the first protection unit and the second protection unit respectively, and is connected in parallel in the main circuit of the corresponding load. The first protection unit is used to bypass the corresponding load; The second protection unit is used for energy discharge; The control unit is used to control the first protection unit to bypass the corresponding load after the second protection unit discharges energy.

[0006] Furthermore, the first protection unit includes a controllable switch and a first capacitor, the controllable switch and the first capacitor are connected in parallel, and the control terminal of the controllable switch is connected to the control unit.

[0007] Furthermore, the second protection unit includes a discharge branch and a drive circuit, wherein: The discharge branch is used to discharge energy; The driving circuit is used to drive the discharge branch to discharge energy when the voltage across the corresponding load is greater than or equal to the discharge action threshold.

[0008] Furthermore, the discharge branch includes a first resistor, a second switching transistor, and a thyristor connected in sequence. The control terminal of the thyristor is connected to the drive circuit, and the control terminal of the second switching transistor is connected to the control unit.

[0009] Furthermore, the driving circuit includes a second resistor, a third resistor, a controllable resistor, a second capacitor, a third capacitor, a first Zener diode, and a second Zener diode, wherein: The second end of the second resistor, the first end of the controllable resistor, and the first end of the third capacitor are connected to the control terminal of the discharge branch. The second end of the second capacitor, the second end of the third resistor, the second end of the controllable resistor, and the second end of the third capacitor are connected to the output terminal of the discharge branch. The first end of the second capacitor, the first end of the third resistor, and the first end of the second resistor are connected to the second end of the first Zener diode. The first end of the first Zener diode is connected to the second end of the second Zener diode. The first end of the second Zener diode is connected to the input terminal of the discharge branch.

[0010] Furthermore, the controllable resistor includes a sampling circuit, a resistor array, and a driving circuit, wherein: The sampling circuit is used to acquire the voltage and current of the controllable resistor; The driving circuit is connected to the control unit, and the driving circuit is used to drive the resistor array to change the resistance value of the controllable resistor.

[0011] Furthermore, the second protection unit also includes a transient suppression diode, which is connected in parallel with the discharge branch.

[0012] Furthermore, the control unit includes a voltage sampling subunit, a current sampling subunit, an analog-to-digital conversion subunit, and a controller, wherein: The voltage sampling subunit is used to collect the voltage of the corresponding load and obtain a voltage signal; The current sampling subunit is used to collect the current of the second protection unit and obtain the current signal; The analog-to-digital conversion subunit is used to convert the voltage signal into a voltage feedback value and the current signal into a current feedback value; The controller is used to determine, based on the current feedback value, that the second protection unit has discharged energy, and then control the first protection unit to bypass the corresponding load; based on the voltage feedback value, it controls the first protection unit to stabilize the voltage of the corresponding load.

[0013] Furthermore, the overvoltage protection system provided in this embodiment of the invention also includes a host computer, which is connected to the control unit.

[0014] Secondly, the present invention provides an overvoltage protection method, applied to the overvoltage protection system described in any of the above embodiments, comprising: The control unit obtains the current feedback value; If the control unit determines that the duration of the current feedback value is greater than the duration threshold and the current feedback value is greater than the current threshold, it determines that the second protection unit has discharged energy and sends a first control signal to the first protection unit to bypass the load.

[0015] Furthermore, the overvoltage protection method provided in this embodiment of the invention further includes: If the control unit determines that the voltage feedback value is less than the discharge action threshold and greater than the adjustment threshold, it sends a third control signal to the first protection unit to stabilize the load voltage.

[0016] The overvoltage protection system and method provided in this invention include multiple loads, with an overvoltage protection module connected in parallel to the input of each load. Each overvoltage protection module includes a first protection unit, a second protection unit, and a control unit. The first and second protection units are connected in parallel with the corresponding loads, and the control unit is connected to the first and second protection units respectively, and is also connected in parallel in the main circuit of the corresponding load. The first protection unit is used to bypass the corresponding load; the second protection unit is used to discharge energy; and the control unit is used to control the first protection unit to bypass the corresponding load after the second protection unit discharges energy, thereby achieving independent overvoltage protection for a single load and improving the reliability of the system. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings: Figure 1 This is a schematic diagram of the overvoltage protection system provided in the first embodiment of the present invention.

[0018] Figure 2 This is a schematic diagram of the overvoltage protection module provided in the second embodiment of the present invention.

[0019] Figure 3This is a schematic diagram of the structure of the first protection unit provided in the third embodiment of the present invention.

[0020] Figure 4 This is a schematic diagram of the structure of the second protection unit provided in the fourth embodiment of the present invention.

[0021] Figure 5 This is a schematic diagram of the structure of the controllable resistor provided in the fifth embodiment of the present invention.

[0022] Figure 6 This is a control principle diagram of the controllable resistor provided in the sixth embodiment of the present invention.

[0023] Figure 7 This is a schematic diagram of the structure of the second protection unit provided in the seventh embodiment of the present invention.

[0024] Figure 8 This is a schematic diagram of the control unit provided in the seventh embodiment of the present invention.

[0025] Figure 9 This is a schematic diagram of the overvoltage protection system provided in the ninth embodiment of the present invention.

[0026] Figure 10 This is a schematic diagram of the overvoltage protection method provided in the tenth embodiment of the present invention. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. Here, the illustrative embodiments and descriptions of the present invention are used to explain the present invention, but are not intended to limit the present invention. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this application can be arbitrarily combined with each other. The acquisition, storage, use, and processing of data in the technical solutions of this application all comply with the relevant provisions of laws and regulations. The user information in the embodiments of this application is obtained through legal and compliant means, and the acquisition, storage, use, and processing of user information have been agreed upon by the customer.

[0028] To facilitate understanding of the technical solution provided in this application, the relevant content of the technical solution in this application will be explained below.

[0029] Existing overvoltage protection strategies for loads lack flexible, tiered response capabilities and rely heavily on rigid protection methods. This makes the system susceptible to over-operation and impact shutdowns when encountering minor overvoltages. Furthermore, it struggles to balance precise control and safety protection when facing severe overvoltages, significantly increasing system cost and complexity. Moreover, the threshold settings of existing protection circuits lack the flexibility to adapt to the highly dynamic load changes in scenarios such as marine power transmission, easily leading to protection delays or malfunctions. In addition, centralized protection architectures suffer from fault isolation deficiencies; single-point faults can easily propagate and cause global failures, and the lack of independent protection and precise isolation mechanisms for individual loads severely restricts the reliability and robustness of marine power transmission systems.

[0030] Therefore, this application proposes a low-power overvoltage protection scheme suitable for marine power transmission, which has a layered flexible protection mechanism, precise and flexible adjustable protection threshold, regional isolation capability, and balances protection accuracy and system continuity, effectively improving the reliability of marine power transmission systems.

[0031] Figure 1 This is a schematic diagram of the overvoltage protection system provided in the first embodiment of the present invention. Figure 2 This is a schematic diagram of the overvoltage protection module provided in the second embodiment of the present invention, as shown below. Figure 1 and Figure 2 As shown, the overvoltage protection system provided in this embodiment of the invention includes multiple loads 101, and an overvoltage protection module 102 is connected in parallel to the input terminal of each load 101, wherein: Each overvoltage protection module 102 includes a first protection unit 1021, a second protection unit 1022, and a control unit 1023. The first protection unit 1021 and the second protection unit 1022 are connected in parallel with the corresponding load 101. The control unit 1023 is connected to the first protection unit 1021 and the second protection unit 1022 respectively, and is connected in parallel in the main circuit of the corresponding load 101. The first protection unit 1021 is used to bypass the corresponding load; The second protection unit 1022 is used for energy discharge; The control unit 1023 is used to control the first protection unit to bypass the corresponding load after the second protection unit performs energy discharge.

[0032] Specifically, electrical energy is transmitted to each load 101 after passing through the power connection plate. Each load 101 has an overvoltage protection module 102 connected in parallel at its input terminal. The overvoltage protection module 102 is used to protect the load 101 from overvoltage.

[0033] Each overvoltage protection module 102 includes a first protection unit 1021, a second protection unit 1022, and a control unit 1023. When the voltage across the load 101 corresponding to the overvoltage protection module 102 is greater than or equal to the discharge action threshold, the second protection unit 1022 of the overvoltage protection module 102 will discharge energy, and then the first protection unit 1021 of the overvoltage protection module 102 will control the first protection unit 1021 to bypass the load 101 to prevent the load 101 from being damaged due to overvoltage.

[0034] By employing a first protection unit and a second protection unit, layered flexible protection is achieved. Each load has an independent overvoltage protection module, providing regional isolation capabilities and overcoming the shortcomings of centralized protection architectures. When not in a protected state, the overvoltage protection system only consumes power from the control unit, resulting in low power consumption.

[0035] like Figure 1 As shown, the power connection plate is connected in series with each load to supply power to each load; the power connection plate can also disconnect the branch where the load 101 is located when the voltage across the two ends of the load 101 is greater than or equal to the discharge action threshold.

[0036] The overvoltage protection system provided in this embodiment of the invention includes multiple loads, with an overvoltage protection module connected in parallel to the input terminal of each load. Each overvoltage protection module includes a first protection unit, a second protection unit, and a control unit. The first protection unit and the second protection unit are connected in parallel with the corresponding loads. The control unit is connected to the first protection unit and the second protection unit respectively, and is connected in parallel in the main circuit of the corresponding load. The first protection unit is used to bypass the corresponding load. The second protection unit is used to discharge energy. After the second protection unit discharges energy, the control unit is used to control the first protection unit to bypass the corresponding load, thereby achieving independent overvoltage protection for a single load and improving the reliability of the system.

[0037] Figure 3 This is a schematic diagram of the structure of the first protection unit provided in the third embodiment of the present invention, as shown below. Figure 3 As shown, the first protection unit 1021 includes a controllable switch P1 and a first capacitor C1. The controllable switch P1 and the first capacitor C1 are connected in parallel, and the control terminal of the controllable switch P1 is connected to the control unit 1023.

[0038] Specifically, the controllable switch P1 is connected in parallel to the input terminal of the corresponding load 101, and the first capacitor C1 is also connected in parallel to the input terminal of the corresponding load 101. The control unit 1023 controls the controllable switch P1 to close when the voltage across the load 101 corresponding to its overvoltage protection module 102 is greater than or equal to the discharge action threshold, bypassing the corresponding load 101, protecting the load 101, and locking the protection state. If the voltage across the load 101 is less than the discharge action threshold, it indicates that the voltage across the load 101 does not require overvoltage protection. The controllable switch P1 can be a metal-oxide-semiconductor field-effect transistor (MOSFET), and the configuration is based on actual needs; this embodiment of the invention does not impose any limitations.

[0039] Because the on-resistance of the controllable switch P1 is small, the power consumption is small when the first protection unit 1021 performs protection action.

[0040] Figure 4 This is a schematic diagram of the structure of the second protection unit provided in the fourth embodiment of the present invention, as shown below. Figure 4 As shown, based on the above embodiments, the second protection unit 1022 further includes a discharge branch 1022-1 and a drive circuit 1022-2, wherein: The venting branch 1022-1 is used to vent energy; The drive circuit 1022-2 is used to drive the discharge branch 1022-1 to discharge energy when the voltage across the corresponding load 101 is greater than or equal to the discharge action threshold.

[0041] Specifically, the discharge branch 1022-1 is connected in parallel with the load 101 corresponding to the second protection unit 1022. When the voltage across the load 101 is greater than or equal to the discharge action threshold, the drive circuit 1022-2 can drive the discharge branch 1022-1 to discharge energy. The control unit 1023 can open or close the discharge branch 1022-1.

[0042] like Figure 4 As shown, the discharge branch 1022-1 includes a first resistor R1, a second switch Q1 and a thyristor T connected in sequence. The control terminal of the thyristor T is connected to the drive circuit 1022-2, and the control terminal of the second switch Q1 is connected to the control unit 1023.

[0043] Specifically, the first end of the first resistor R1 is connected to the first end of the load, the second end of the first resistor R1 is connected to the input end of the second switch Q1, the control end of the second switch Q1 is connected to the control unit, the output end of the second switch Q1 is connected to the anode of the thyristor T, the cathode of the thyristor T is connected to the second end of the load, and the control electrode of the thyristor T is connected to the drive circuit 1022-2.

[0044] Control unit 1023 disconnects the discharge branch 1022-1 by controlling the second switch Q1 to turn off, and turns the second switch Q1 to turn on, thus opening the discharge branch 1022-1. When the discharge branch 1022-1 discharges energy, the silicon controlled rectifier (SCR) T quickly turns on, and the overvoltage discharges energy rapidly through the path formed by the first resistor R1, the second switch Q1, and the SCR T.

[0045] like Figure 4 As shown, the driving circuit 1022-2 includes a second resistor R2, a third resistor R3, a controllable resistor R4, a second capacitor C2, a third capacitor C3, a first Zener diode Z1, and a second Zener diode Z2, wherein: The second terminal of the second resistor R2, the first terminal of the controllable resistor R4, and the first terminal of the third capacitor C3 are connected to the control terminal of the bleedering branch 1022-1. The second terminal of the second capacitor C2, the second terminal of the third resistor R3, the second terminal of the controllable resistor R4, and the second terminal of the third capacitor C3 are connected to the output terminal of the bleedering branch 1022-1. The first terminal of the second capacitor C2, the first terminal of the third resistor R3, and the first terminal of the second resistor R2 are connected to the second terminal of the first Zener diode Z1. The first terminal of the first Zener diode Z1 is connected to the second terminal of the second Zener diode Z2. The first terminal of the second Zener diode Z2 is connected to the input terminal of the bleedering branch 1022-1.

[0046] Specifically, when the voltage across the load 101 corresponding to the overvoltage protection module 102 is greater than or equal to the discharge action threshold, the second protection unit 1022 has established a driving voltage across the controllable resistor R4, providing a driving current to turn on the thyristor T. However, when the voltage across the load 101 corresponding to the overvoltage protection module 102 is less than the discharge action threshold, the voltage across R4 has not reached the minimum voltage value required for the thyristor T to turn on. By changing the resistance value of the controllable resistor R4, the protection threshold of the second protection unit 1022 can be adjusted.

[0047] Figure 5 This is a schematic diagram of the structure of the controllable resistor provided in the fifth embodiment of the present invention, as shown below. Figure 5 As shown, the controllable resistor R4 includes a sampling circuit 501, a resistor array 502, and a driving circuit (not shown in the figure), wherein: The sampling circuit 501 is used to collect the voltage and current of the controllable resistor R4; The drive circuit is connected to the control unit 1023, and the drive circuit is used to drive the resistor array 502 to change the resistance value of the controllable resistor R4.

[0048] Specifically, the sampling circuit 501 may include a current sampling unit 501-1, a voltage sampling unit 501-2, a first voltage follower A1, a second voltage follower A2, a third voltage follower A2, and a sampling resistor R5; the first terminal of the sampling resistor R5 is connected to the input terminal IN of the controllable resistor R4, and the second terminal of the sampling resistor R5 is connected to the resistor array 502; the first input terminal of the first voltage follower A1 is connected to the first terminal of the sampling resistor R5, and the second input terminal of the first voltage follower A1 is connected to the output terminal of the first voltage follower A1; the first input terminal of the second voltage follower A2 is connected to the second terminal of the sampling resistor R5, and the second voltage follower A2... The second input terminal of voltage follower A2 is connected to the output terminal of the second voltage follower A2; the first terminal of current sampling unit 501-1 is connected to the output terminal of the first voltage follower A1, and the second terminal of current sampling unit 501-1 is connected to the output terminal of the second voltage follower A2; the first input terminal of the third voltage follower A2 is connected to the output terminal OUT of the controllable resistor R4, the second input terminal of the third voltage follower A2 is connected to the output terminal of the third voltage follower A2, the first terminal of voltage sampling unit 501-2 is connected to the output terminal of the first voltage follower A1, and the second terminal of voltage sampling unit 501-2 is connected to the output terminal of the third voltage follower A2.

[0049] The control unit is connected to the voltage sampling unit 501-2 and the current sampling unit 501-1 respectively. Based on the voltage V obtained by the voltage sampling unit 501-2 and the current I obtained by the current sampling unit 501-1, the resistance value r of the controllable resistor R4 can be calculated, r = V / I. The voltage follower isolates the sampling circuit from the original circuit, preventing the sampling circuit from affecting the original circuit.

[0050] The resistor array 502 includes multiple resistor units 502-1 connected in series. Each resistor unit 502-1 includes a switching element and a resistor. The first resistor unit includes a switching element K1 and a resistor R connected in parallel. k1 The second resistor unit includes a switching element K2 and a resistor R connected in parallel. k2 The Nth resistor unit includes a switching element KN and a resistor R connected in parallel. kN N represents the total number of resistor units 502-1 included in the resistor array 502, which is set according to actual needs and is not limited in this embodiment of the invention. If the first resistor unit includes a resistor R k1 If the resistance value is r0, then the second resistance unit includes resistance R.k2 The resistance value is 2r0, and the third resistance unit includes resistor R. k3 The resistance value is 2 2 r0, ..., the resistance R included in the Nth resistance unit kN The resistance value is 2 N-1 r0.

[0051] The driving circuit controls the switching elements included in the resistor unit 502-1 to close, thus short-circuiting the corresponding resistor; and controls the switching elements included in the resistor unit 502-1 to open, thus connecting the corresponding resistor to the circuit. The driving circuit is connected to the control unit 1023, and under the resistor array control signal of the control unit 1023, controls the short-circuiting and connection of the resistors included in each resistor unit 502-1 in the resistor array 502, thereby changing the resistance value of the controllable resistor R4.

[0052] for Figure 4 The second protection unit shown, control unit 1023, can calculate the resistance value of the controllable resistor R4 corresponding to the current discharge action threshold based on the discharge action threshold. The resistance value r4 of the controllable resistor corresponding to the current discharge action threshold can be calculated using the formula: r4 = r²V GT / (V set -V Z -V GT ) is calculated to obtain, where V GT It is the gate trigger voltage of the thyristor T, V set V is the current discharge action threshold. Z r4 is the series voltage regulation value of the first Zener diode Z1 and the second Zener diode Z2, and r2 is the resistance value of the second resistor R2. Then, based on r4, a control signal is generated to control the target resistance value of the resistor array 502. The control unit 1023 calculates the error based on the sampled resistance value and the target resistance value, and inputs the error to the PI controller. This generates a control drive circuit to change the switching combination of the resistor array, thereby adjusting the actual resistance value of the controllable resistor R4, achieving the purpose of changing the discharge action threshold. Figure 6 As shown.

[0053] Figure 7 This is a schematic diagram of the structure of the second protection unit provided in the seventh embodiment of the present invention, as shown below. Figure 7 As shown, based on the above embodiments, the second protection unit 1022 further includes a transient voltage suppressor (TVS) Z3, which is connected in parallel with the discharge branch 1022-1. The transient voltage suppressor Z3 is used to suppress transient voltage spikes and perform transient discharge.

[0054] Figure 8This is a schematic diagram of the control unit provided in the seventh embodiment of the present invention, as shown below. Figure 8 As shown, based on the above embodiments, the control unit 1023 further includes a voltage sampling subunit 1023-1, a current sampling subunit 1023-2, an analog-to-digital conversion subunit 1023-3, and a controller 1023-4, wherein: The voltage sampling subunit 1023-1 is used to acquire the voltage of the corresponding load 101 and obtain the voltage signal; The current sampling subunit 1023-2 is used to collect the current of the second protection unit 1022 and obtain the current signal; The analog-to-digital conversion subunit 1023-3 is used to convert the voltage signal into a voltage feedback value and the current signal into a current feedback value; The controller 1023-4 is used to determine, based on the current feedback value, that after the second protection unit 1022 has discharged energy, control the first protection unit 1021 to bypass the corresponding load 101; and based on the voltage feedback value, control the first protection unit 1021 to stabilize the voltage of the corresponding load 101.

[0055] Specifically, the voltage sampling subunit 1023-1 is used to collect the voltage signal of the corresponding load 101, and then transmit the voltage signal to the analog-to-digital conversion subunit 1023-3 for analog-to-digital conversion. The analog-to-digital conversion subunit 1023-3 converts the voltage signal into a digital signal to obtain the voltage feedback value. The current sampling subunit 1023-2 is used to collect the current of the second protection unit 1022 to obtain the current signal. It can collect the current magnitude of the second protection unit 1022 when discharging energy, and then transmit the current signal to the analog-to-digital conversion subunit 1023-3 for analog-to-digital conversion. The analog-to-digital conversion subunit 1023-3 converts the current signal into a digital signal to obtain the current feedback value.

[0056] When the voltage across load 101 is greater than or equal to the discharge action threshold, the second protection unit 1022 automatically activates the thyristor T. The controller 1023-4 and the second switch Q1 control the opening and closing of the second switch Q1 to enable or disable the energy discharge function of the second protection unit 1022.

[0057] After receiving a continuous current feedback value, the controller 1023-4 determines that the second protection unit 1022 should discharge energy. After a delay time t, it sends a control signal to the first protection unit 1021 to bypass the load. The time t can be set according to actual needs, and this embodiment of the invention does not impose a limitation.

[0058] Understandably, in order for the energy discharge function of the second protection unit 1022 to take effect, the second switch Q1 needs to be turned on in advance. If the second switch Q1 is turned off, the energy discharge function of the second protection unit 1022 will be disabled.

[0059] Control commands can be sent from the host computer to enable the controller 1023-4 to turn on the second switch Q1. When the overvoltage protection module 102 is activated, the second switch Q1 is normally open.

[0060] If the current sampling subunit 1023-2 detects a continuous and stable current feedback value, the controller 1023-4 can determine that the second protection unit 1022 has automatically activated the discharge function. After a delay time t, the controller 1023-4 sends a control signal to the first protection unit 1021 to bypass the load 101.

[0061] The voltage feedback value obtained by sampling through the voltage sampling subunit 1023-1 is compared with the adjustment threshold of pulse width modulation. If the voltage feedback value is greater than the adjustment threshold and less than the discharge action threshold, a control signal is sent to the first protection unit 1021 to start pulse width modulation to stabilize the voltage across the load 101. That is, a control signal is sent to the controllable switch P1 of the first protection unit 1021 to start the pulse width modulation adjustment mode. The controllable switch P1 of the first protection unit 1021 is controlled to turn on and off by outputting a drive signal with a specific duty cycle.

[0062] By changing the resistance value of the controllable resistor R4 through the controller 1023-4, the automatic protection threshold of the second protection unit 1022, i.e., the discharge action threshold, can be changed. For example, the voltage sampling subunit 1023-1 can be directly connected in parallel across the corresponding load 101. The current sampling subunit 1023-2 can use a current sensor, such as... Figure 4 and Figure 7 As shown, the current sensor U is connected in series with the discharge branch 1022-1 to collect the current of the discharge branch 1022-1 when energy is discharged.

[0063] Based on the above embodiments, the control unit 1023 further includes comparator U1 and comparator U2, wherein: The output of voltage sampling subunit 1023-1 is connected to the first input of comparator U1, the second input of comparator U1 is connected to the output of comparator U1, and the output of comparator U1 is connected to the input of analog-to-digital converter subunit 1023-3; the output of current sampling subunit 1023-2 is connected to the first input of comparator U2, the second input of comparator U2 is connected to the output of comparator U2, and the output of comparator U2 is connected to the input of analog-to-digital converter subunit 1023-3; the output of analog-to-digital converter subunit 1023-3 is connected to controller 1023-4.

[0064] Figure 9 This is a schematic diagram of the overvoltage protection system provided in the ninth embodiment of the present invention, as shown below. Figure 9 As shown, based on the above embodiments, the overvoltage protection system provided in this embodiment of the invention further includes a host computer 103, which is connected to each overvoltage protection module 102.

[0065] Specifically, each overvoltage protection module 102 can independently interact with the host computer 103.

[0066] For example, the host computer 103 can send the discharge action threshold to the control unit 1023.

[0067] Figure 10 This is a schematic diagram of the overvoltage protection method provided in the tenth embodiment of the present invention, as shown below. Figure 10 As shown, the overvoltage protection method provided in this embodiment of the invention is applied to the overvoltage protection system described in any of the above embodiments, and includes: S1001, The control unit obtains the current feedback value; Specifically, current sampling of the second protection unit yields a current feedback value, which the control unit then receives. The load corresponding to the overvoltage protection module to which the control unit belongs is also the load corresponding to the control unit. The current feedback value is used to determine whether the second protection unit has discharged energy.

[0068] S1002. If the control unit determines that the duration of the current feedback value is greater than the duration threshold and the current feedback value is greater than the current threshold, it determines that the second protection unit has discharged energy and sends a first control signal to the first protection unit to bypass the load. Specifically, the control unit records the duration of continuously received current feedback values ​​as the current feedback value duration, compares the current feedback value duration with a duration threshold, and compares the current feedback value with a current threshold. If the current feedback value duration is greater than the duration threshold and the current feedback value is greater than the current threshold, it indicates that a continuous and stable current feedback value has been received. Then, it is determined that the second protection unit has discharged energy, and a first control signal is sent to the first protection unit to bypass the load corresponding to the control unit.

[0069] The duration threshold can be set according to actual needs, such as 1 second; however, this embodiment of the invention does not impose a limitation. The current threshold can be set based on practical experience; this embodiment of the invention does not impose a limitation.

[0070] The overvoltage protection system provided in this embodiment of the invention includes a control unit that acquires a current feedback value. If the control unit determines that the duration of the current feedback value is greater than a duration threshold and the current feedback value is greater than a current threshold, it determines that the second protection unit has discharged energy and sends a first control signal to the first protection unit to bypass the load. If the control unit determines that the voltage feedback value is less than the discharge action threshold and greater than the adjustment threshold, it sends a third control signal to the first protection unit to stabilize the load voltage, thereby achieving overvoltage protection for the load and improving the reliability of overvoltage protection.

[0071] Based on the above embodiments, the overvoltage protection method provided by the embodiments of the present invention further includes: If the control unit determines that the voltage feedback value is less than the discharge action threshold and greater than the adjustment threshold, it sends a third control signal to the first protection unit to stabilize the load voltage.

[0072] Specifically, the control unit acquires a voltage feedback value, which is obtained by detecting the voltage across the load corresponding to the overvoltage protection module to which the control unit belongs. If the voltage feedback value is less than the discharge action threshold, it is compared with an adjustment threshold. If the voltage feedback value is greater than the adjustment threshold, a third control signal is sent to the first protection unit to activate the pulse width modulation adjustment mode. This mode controls the on / off state of the controllable switch of the first protection unit by outputting a drive signal with a specific duty cycle, thereby controlling the voltage across the capacitor included in the first protection unit and stabilizing it within a certain range. Since the capacitor included in the first protection unit is connected in parallel with the load, controlling the voltage across the capacitor is equivalent to controlling the voltage across the load, thus stabilizing the load voltage. The discharge action threshold and the adjustment threshold are set according to actual needs, and this embodiment of the invention does not impose limitations. Adjusting the voltage across the load through the first protection unit improves the stability of the voltage across the load and also helps prevent overvoltage.

[0073] Based on the above embodiments, the control unit further sends an error prompt signal to the host computer after determining that the voltage feedback value is greater than the discharge action threshold.

[0074] Specifically, after the control unit determines that the voltage feedback value is greater than the discharge action threshold, it can send an error prompt signal to the host computer to indicate that the load has overvoltage.

[0075] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0076] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0077] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0078] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0079] In the description of this specification, the references to terms such as "an embodiment," "a specific embodiment," "some embodiments," "for example," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0080] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An overvoltage protection system, characterized in that, It includes multiple loads, with an overvoltage protection module connected in parallel at the input of each load, wherein: Each overvoltage protection module includes a first protection unit, a second protection unit, and a control unit. The first protection unit and the second protection unit are connected in parallel with the corresponding load. The control unit is connected to the first protection unit and the second protection unit respectively, and is connected in parallel in the main circuit of the corresponding load. The first protection unit is used to bypass the corresponding load; The second protection unit is used for energy discharge; The control unit is used to control the first protection unit to bypass the corresponding load after the second protection unit discharges energy.

2. The overvoltage protection system according to claim 1, characterized in that, The first protection unit includes a controllable switch and a first capacitor. The controllable switch is connected in parallel with the first capacitor, and the control terminal of the controllable switch is connected to the control unit.

3. The overvoltage protection system according to claim 1, characterized in that, The second protection unit includes a discharge branch and a drive circuit, wherein: The discharge branch is used to discharge energy; The driving circuit is used to drive the discharge branch to discharge energy when the voltage across the corresponding load is greater than or equal to the discharge action threshold.

4. The overvoltage protection system according to claim 3, characterized in that, The discharge branch includes a first resistor, a second switching transistor, and a thyristor connected in sequence. The control terminal of the thyristor is connected to the drive circuit, and the control terminal of the second switching transistor is connected to the control unit.

5. The overvoltage protection system according to claim 3, characterized in that, The driving circuit includes a second resistor, a third resistor, a controllable resistor, a second capacitor, a third capacitor, a first Zener diode, and a second Zener diode, wherein: The second end of the second resistor, the first end of the controllable resistor, and the first end of the third capacitor are connected to the control terminal of the discharge branch. The second end of the second capacitor, the second end of the third resistor, the second end of the controllable resistor, and the second end of the third capacitor are connected to the output terminal of the discharge branch. The first end of the second capacitor, the first end of the third resistor, and the first end of the second resistor are connected to the second end of the first Zener diode. The first end of the first Zener diode is connected to the second end of the second Zener diode. The first end of the second Zener diode is connected to the input terminal of the discharge branch.

6. The overvoltage protection system according to claim 5, characterized in that, The controllable resistor includes a sampling circuit, a resistor array, and a driving circuit, wherein: The sampling circuit is used to acquire the voltage and current of the controllable resistor; The driving circuit is connected to the control unit, and the driving circuit is used to drive the resistor array to change the resistance value of the controllable resistor.

7. The overvoltage protection system according to claim 3, characterized in that, The second protection unit also includes a transient suppression diode, which is connected in parallel with the discharge branch.

8. The overvoltage protection system according to claim 1, characterized in that, The control unit includes a voltage sampling subunit, a current sampling subunit, an analog-to-digital conversion subunit, and a controller, wherein: The voltage sampling subunit is used to collect the voltage of the corresponding load and obtain a voltage signal; The current sampling subunit is used to collect the current of the second protection unit and obtain the current signal; The analog-to-digital conversion subunit is used to convert the voltage signal into a voltage feedback value and the current signal into a current feedback value; The controller is used to determine, based on the current feedback value, that the second protection unit has discharged energy, and then control the first protection unit to bypass the corresponding load; based on the voltage feedback value, it controls the first protection unit to stabilize the voltage of the corresponding load.

9. The overvoltage protection system according to any one of claims 1 to 8, characterized in that, It also includes a host computer, which is connected to the control unit.

10. An overvoltage protection method, characterized in that, The overvoltage protection system according to any one of claims 1 to 9 comprises: The control unit acquires the current feedback value; If the control unit determines that the duration of the current feedback value is greater than the duration threshold and the current feedback value is greater than the current threshold, it determines that the second protection unit has discharged energy and sends a first control signal to the first protection unit to bypass the load.

11. The method according to claim 10, characterized in that, Also includes: If the control unit determines that the voltage feedback value is less than the discharge action threshold and greater than the adjustment threshold, it sends a third control signal to the first protection unit to stabilize the load voltage.

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