Overvoltage protection device and overvoltage protection method

Abstract

The invention provides an overvoltage protection device and an overvoltage protection method, which can utilize a processor to detect the stoping voltage of a voltage acquisition circuit, and if the stoping voltage exceeds a first voltage limit range, a first cut-off instruction is sent to a first overvoltage protection circuit to cut off the transmission of bipolar voltage by the first overvoltage protection circuit; moreover, in order to improve the accuracy of the overvoltage protection of the bipolar voltage, the bipolar voltage transmitted by the first overvoltage protection circuit is detected by using the second overvoltage protection circuit, and if the bipolar voltage exceeds a second voltage limiting range, the transmission of the bipolar voltage by the second overvoltage protection circuit is cut off. Therefore, the overlarge bipolar voltage is prevented from being transmitted to the load through the voltage acquisition circuit, and the load can be ensured to always work in a normal voltage range through dual overvoltage protection of the first overvoltage protection circuit and the second overvoltage protection circuit.

Description

Technical Field

[0001] This application relates to the field of circuit control technology, and in particular to an overvoltage protection device and overvoltage protection method. Background Technology

[0002] To prevent overvoltage situations, some power supply circuits implement overvoltage protection. This typically involves directly sampling the power supply circuit's voltage to determine if it exceeds a predetermined range, and then deciding whether to activate the overvoltage protection.

[0003] However, this overvoltage protection scheme is not accurate enough and is prone to errors, which may cause the downstream load to malfunction or be damaged. Summary of the Invention

[0004] In view of this, the purpose of this application is to provide an overvoltage protection device and overvoltage protection method to solve or partially solve the above-mentioned technical problems.

[0005] Based on the above objectives, this application proposes an overvoltage protection device, comprising: a processor, a bidirectional power supply, a first overvoltage protection circuit, a second overvoltage protection circuit, and a voltage acquisition circuit connected in sequence. The processor is also connected to the voltage acquisition circuit and the first overvoltage protection circuit, and is configured to receive the sampled voltage from the voltage acquisition circuit, and in response to the sampled voltage exceeding the first voltage limit range, issue a first cut-off command to the first overvoltage protection circuit. The bidirectional power supply is configured to output a bipolar voltage to the first overvoltage protection circuit. The first overvoltage protection circuit is configured to transmit the bipolar voltage to the second overvoltage protection circuit, and to cut off the transmission of the bipolar voltage in response to receiving the first cut-off command. The second overvoltage protection circuit is configured to transmit the bipolar voltage to the voltage acquisition circuit, and to cut off the transmission of the bipolar voltage in response to the bipolar voltage exceeding the second voltage limit range. The voltage acquisition circuit, connected to the load, is configured to transmit the bipolar voltage to the load, and simultaneously sample the bipolar voltage to determine the sampled voltage and send it to the processor.

[0006] Based on the same concept, this application also proposes an overvoltage protection method, applied to the overvoltage protection device described in the above embodiments, the method comprising: Using a bidirectional power supply, a bipolar voltage is output to the first overvoltage protection circuit; In response to determining that the voltage sampling voltage of the voltage acquisition circuit exceeds a first voltage limit range, the processor determines a first cut-off command to instruct the first overvoltage protection circuit to cut off the transmission of the bipolar voltage according to the first cut-off command; or, in response to determining that the voltage sampling voltage of the voltage acquisition circuit is within the first voltage limit range, the processor determines a first run command to transmit the bipolar voltage to the second overvoltage protection circuit according to the first run command. The bipolar voltage transmitted from the first overvoltage protection circuit is detected using the second overvoltage protection circuit. In response to the bipolar voltage exceeding the second voltage limit range, the transmission of the bipolar voltage is cut off, or in response to the bipolar voltage being within the second voltage limit range, the bipolar voltage is transmitted to the voltage acquisition circuit. The voltage acquisition circuit is used to provide the bipolar voltage to the load.

[0007] As can be seen from the above, the overvoltage protection device and overvoltage protection method provided in this application can use the processor to detect the voltage sampled by the voltage acquisition circuit. If it exceeds the first voltage limit range, a first cut-off command will be sent to the first overvoltage protection circuit to cut off the transmission of the bipolar voltage by the first overvoltage protection circuit. Furthermore, in order to improve the accuracy of overvoltage protection of the bipolar voltage, a second overvoltage protection circuit will also be used to detect the bipolar voltage transmitted from the first overvoltage protection circuit. If it exceeds the second voltage limit range, the transmission of the bipolar voltage by the second overvoltage protection circuit will be disconnected, thereby ensuring that the excessively high bipolar voltage will not be transmitted to the load through the voltage acquisition circuit. Through the dual overvoltage protection of the first and second overvoltage protection circuits, it can be ensured that the load always operates within the normal voltage range. Attached Figure Description

[0008] To more clearly illustrate the technical solutions in this application or related technologies, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0009] Figure 1 This is a schematic diagram of a voltage protection circuit in related technologies.

[0010] Figure 2 This is a schematic diagram of the overvoltage protection device according to an embodiment of this application.

[0011] Figure 3 This is a schematic diagram of the overvoltage protection device according to another embodiment of this application.

[0012] Figure 4 This is a circuit diagram of the spike voltage protection circuit and the power amplifier output circuit according to an embodiment of this application.

[0013] Figure 5 This is a circuit diagram of the first overvoltage protection circuit according to an embodiment of this application.

[0014] Figure 6 This is a circuit diagram of the second overvoltage protection circuit according to an embodiment of this application.

[0015] Figure 7 This is a flowchart of an overvoltage protection method according to an embodiment of this application.

[0016] Explanation of reference numerals in the attached figures: 100 Overvoltage protection device; 101 processor; 102 Bidirectional power supply, 1021 Digital-to-analog converter, 1022 Peak voltage protection circuit, R28 First voltage divider resistor, R20 Second voltage divider resistor, 10221 Bidirectional voltage regulator circuit, D3 First Zener diode, D4 ​​Second Zener diode, 1023 Power amplifier output circuit, U5 Power operational amplifier, 10231 Feedback circuit, 10232 Current limiting resistor, 10233 Filter capacitor; 103 First overvoltage protection circuit, Q1 transistor circuit, U6 First optocoupler circuit; 104 Second overvoltage protection circuit, U28 Relay circuit, 1041 Detection circuit, 10411 Absolute value circuit, 10412 Voltage detection circuit, U21 Second optocoupler circuit; 105 voltage acquisition circuit. Detailed Implementation

[0017] It is understood that the data involved in this technical solution (including but not limited to the data itself, the acquisition or use of the data) shall comply with the requirements of relevant laws, regulations and related provisions.

[0018] The principles and spirit of this application will now be described with reference to several exemplary embodiments. It should be understood that these embodiments are provided merely to enable those skilled in the art to better understand and implement this application, and are not intended to limit the scope of this application in any way. Rather, these embodiments are provided to make this application more thorough and complete, and to fully convey the scope of this application to those skilled in the art.

[0019] It should be noted that, unless otherwise defined, the technical or scientific terms used in the embodiments of this application should have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "first," "second," and similar terms used in the embodiments of this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are only used to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0020] In this article, it is important to understand that any number of elements in the accompanying figures is for illustrative purposes and not for limitation, and any naming is for distinction only and has no limiting meaning.

[0021] Overvoltage protection circuits in related technologies (such as) Figure 1 As shown), the following situations also exist: The core mechanism of the overvoltage protection circuit is to use feedback control principles to effectively protect the voltage. In this circuit, the output voltage is acquired and the acquired voltage signal is fed back to the DSP (Digital Signal Processor) for comparison with a reference value. When the detected voltage value exceeds the preset reference value, overvoltage protection is activated. This overvoltage protection scheme is widely used in many circuits with high voltage stability requirements, effectively preventing circuit failures or component damage caused by overvoltage, thus ensuring the safe and stable operation of the entire circuit.

[0022] However, conventional overvoltage protection circuits are no longer sufficient to meet voltage protection requirements. When bipolar voltage, voltage spikes, acquisition circuit failure, or DSP malfunction occurs, the circuit cannot provide timely overvoltage protection, ultimately leading to the downstream load malfunctioning or being severely damaged.

[0023] The problems and defects that have occurred are as follows: Bipolar voltage cannot be acquired, voltage feedback protection has a time delay, peak voltage cannot be accurately acquired, or software operation failure causes protection to fail.

[0024] Based on the above description, the principles and spirit of this application will be explained in detail below with reference to several representative embodiments.

[0025] This application provides an overvoltage protection device 100, such as... Figure 2 As shown, it includes: a processor 101, a bidirectional power supply 102, a first overvoltage protection circuit 103, a second overvoltage protection circuit 104, and a voltage acquisition circuit 105 connected in sequence.

[0026] The processor 101 is also connected to the voltage acquisition circuit 105 and the first overvoltage protection circuit 103, and is configured to receive the sampled voltage from the voltage acquisition circuit 105, and issue a first cut-off command to the first overvoltage protection circuit 103 in response to the sampled voltage exceeding the first voltage limit range.

[0027] The bidirectional power supply 102 is configured to output a bipolar voltage to the first overvoltage protection circuit 103.

[0028] The first overvoltage protection circuit 103 is configured to transmit a bipolar voltage to the second overvoltage protection circuit 104, and to cut off the transmission of the bipolar voltage in response to receiving a first cut-off command.

[0029] The second overvoltage protection circuit 104 is configured to transmit the bipolar voltage to the voltage acquisition circuit 105 and cut off the transmission of the bipolar voltage in response to the bipolar voltage exceeding the second voltage limit range.

[0030] The voltage acquisition circuit 105, connected to the load, is configured to transmit bipolar voltage to the load and simultaneously sample the bipolar voltage to determine the sampled voltage and send it to the processor 101.

[0031] In practice, software overvoltage protection is first implemented: this is accomplished by the processor 101 controlling the first overvoltage protection circuit 103.

[0032] The processor 101 can detect the voltage sampled by the voltage acquisition circuit 105. If the voltage does not exceed the first voltage limit, it will send a first operation command (e.g., a low-level Do signal) to the first overvoltage protection circuit 103, so that the first overvoltage protection circuit 103 can normally deliver the bipolar voltage from the bidirectional power supply 102. If the processor 101 detects that the sampled voltage exceeds the first voltage limit, it will send a first cut-off command (e.g., a high-level Do signal) to the first overvoltage protection circuit 103, thereby cutting off the delivery of the bipolar voltage and preventing the excessively high bipolar voltage from being delivered and causing adverse effects on the load.

[0033] Secondly, hardware overvoltage protection is implemented: this is accomplished by the second overvoltage protection circuit 104.

[0034] The second overvoltage protection circuit 104 will re-detect the bipolar voltage. If it does not exceed the second voltage limit range, the bipolar voltage will be transmitted normally; if it exceeds the second voltage limit range, the transmission of the bipolar voltage will be cut off.

[0035] The first voltage limit range and the second voltage limit range can be the same or different, and can be set according to the actual overvoltage protection requirements.

[0036] The first scenario: The first voltage limit range and the second voltage limit range are the same value, for example, both from -3V to 3V.

[0037] The second scenario: The first voltage limit range and the second voltage limit range are different values. For example, the first voltage limit range is -3V to 3V, and the second voltage limit range is -2.5V to 2.5V.

[0038] By utilizing the above scheme and the dual overvoltage protection of the first overvoltage protection circuit 103 and the second overvoltage protection circuit 104, it is ensured that the excessively high bipolar voltage will not be transmitted to the load through the voltage acquisition circuit 105, and the load will always operate within the normal voltage range.

[0039] In some embodiments, such as Figure 3 As shown, the bidirectional power supply 102 includes: The digital-to-analog converter 1021 is connected to the processor 101 and is configured to perform digital-to-analog conversion control on the digital signal sent by the processor 101, transmit bipolar voltage, sample the bipolar voltage output, and send the sampled voltage output to the processor 101. The processor 101 is configured to detect the output sampling voltage sent by the digital-to-analog converter 1021, and in response to the output sampling voltage exceeding the third voltage limit range, send a stop command to the digital-to-analog converter 1021 to stop the bipolar voltage transmission through the digital-to-analog converter 1021.

[0040] In practice, the third voltage limit range can be the same as or different from the first or second voltage limit range, and can be set according to the actual overvoltage protection requirements.

[0041] The first scenario: The third voltage limit range is the same as the first voltage limit range, for example, both are -3V to 3V; or the third voltage limit range is different from the second voltage limit range, for example, the third voltage limit range is -3V to 3V and the second voltage limit range is -2.5V to 2.5V.

[0042] The second scenario: The third voltage limit range is the same as the second voltage limit range, for example, both are -3V to 3V; or the third voltage limit range is different from the first voltage limit range, for example, the third voltage limit range is -3V to 3V and the first voltage limit range is -2.5V to 2.5V.

[0043] The third scenario: The first voltage limit range, the second voltage limit range, and the third voltage limit range are the same value, for example, all of them are -3V to 3V, or all of them are -2.5V to 2.5V.

[0044] The fourth scenario: The first, second, and third voltage limit ranges are all different, and the corresponding range sizes are in the following order: the first voltage limit range is smaller than the second voltage limit range, and the second voltage limit range is smaller than the third voltage limit range. That is, the first voltage limit range ∈ the second voltage limit range ∈ the third voltage limit range. For example, the first voltage limit range is -2V to 2V, the second voltage limit range is -2.5V to 2.5V, and the third voltage limit range is -3V to 3V.

[0045] Initial software overvoltage protection: Processor 101 works in conjunction with digital-to-analog converter 1021.

[0046] The processor 101 can sample the output voltage obtained by the digital-to-analog converter 1021 in the bidirectional power supply 102 after digital-to-analog conversion in real time. If it does not exceed the third voltage limit range, the bipolar voltage transmission will proceed normally. If it exceeds the third voltage limit range, the processor 101 will generate a stop command and send it to the digital-to-analog converter 1021, thereby stopping the bipolar voltage transmission.

[0047] Through the above scheme, the processor 101 can work with the digital-to-analog converter 1021 in the bidirectional power supply 102 to complete the initial software overvoltage protection process. In this way, if an overvoltage is detected during the initial transmission phase of the bidirectional power supply 102, the bipolar voltage transmission can be stopped in time.

[0048] In some embodiments, such as Figure 3 As shown, the bidirectional power supply 102 also includes: The spike voltage protection circuit 1022 is connected to the digital-to-analog converter 1021 and is configured to perform voltage regulation control on the bipolar voltage transmitted by the digital-to-analog converter 1021 to obtain the regulated bipolar voltage. The power amplifier output circuit 1023 is connected to the peak voltage protection circuit 1022 and the first overvoltage protection circuit 103 respectively, and is configured to amplify the bipolar voltage after voltage regulation and send the amplified bipolar voltage to the first overvoltage protection circuit 103.

[0049] In practice, the initial hardware overvoltage protection is achieved by the spike voltage protection circuit 1022 working in conjunction with the power amplifier output circuit 1023.

[0050] The spike voltage protection circuit 1022 can suppress the spike voltage of the bipolar voltage controlled and transmitted by the digital-to-analog converter 1021, ensuring that the voltage after passing through the spike voltage protection circuit 1022 can be output stably, achieving the purpose of voltage regulation control, and obtaining the regulated bipolar voltage. After being amplified by the power amplifier output circuit 1023, the amplified bipolar voltage is sent to the first overvoltage protection circuit 103.

[0051] The above solution utilizes the spike voltage protection circuit 1022 to prevent instantaneous spike voltage from affecting the output of the power amplifier output circuit 1023, thus avoiding damage to the downstream load.

[0052] In some embodiments, such as Figure 4 As shown, the spike voltage protection circuit 1022 includes: The first voltage divider resistor R28 is connected at one end to the digital-to-analog converter 1021 and at the other end to the power amplifier output circuit 1023. It is configured to divide the bipolar voltage controlled and transmitted by the digital-to-analog converter 1021. The second voltage divider resistor R20 has one end connected to the connection between the first voltage divider resistor R28 and the power amplifier output circuit 1023, and the other end grounded. It is configured to divide the bipolar voltage controlled and transmitted by the digital-to-analog converter 1021. The bidirectional voltage regulator circuit 10221 has one end connected to the connection between the first voltage divider resistor R28 and the power amplifier output circuit 1023, and the other end grounded. It is configured to turn on when the bipolar voltage exceeds the set voltage regulation range, so that the current flowing through the first voltage divider resistor R28 increases, the voltage divided by the first voltage divider resistor R28 increases, and the bipolar voltage after voltage regulation is transmitted to the power amplifier output circuit 1023.

[0053] In practical implementation, the first voltage divider resistor R28 and the second voltage divider resistor R20 function as voltage dividers. The bidirectional voltage regulator circuit 10221 includes a first voltage regulator diode D3 and a second voltage regulator diode D4 connected in series. If the bipolar voltage exceeds the set voltage regulation range, the first voltage regulator diode D3 and the second voltage regulator diode D4 conduct, which increases the current in the first voltage divider resistor R28. Since the resistance value of the first voltage divider resistor R28 remains unchanged, resistance value × current = voltage. Therefore, the voltage divided by the first voltage divider resistor R28 increases, thereby reducing the bipolar voltage and obtaining the regulated bipolar voltage. This ensures that the regulated bipolar voltage transmitted to the power amplifier output circuit 1023 has a stable voltage, effectively reducing the impact of peak transient voltages.

[0054] In some embodiments, such as Figure 4 As shown, the power amplifier output circuit 1023 includes: The power operational amplifier U5, with its positive input terminal connected to the spike voltage protection circuit 1022, is configured to amplify the power of the regulated bipolar voltage. Feedback circuit 10231 is disposed between the negative input terminal (e.g., -IN) and the output terminal (e.g., +IN) of power operational amplifier U5, and is configured to feed back the amplified bipolar voltage to power operational amplifier U5 for power amplification adjustment. The current limiting resistor 10232 is set at the output terminal (e.g., OUT) of the power operational amplifier U5 and is configured to limit the maximum output current of the power operational amplifier U5. The filter capacitor 10233, connected to the positive (e.g., +Vs) and negative (e.g., -Vs) terminals of the power operational amplifier U5, is configured to filter the power supply of the power operational amplifier U5.

[0055] In a specific implementation, the feedback circuit 10231 includes: a first resistor R21, one end of which is connected to the negative input terminal of the power operational amplifier U5 and the other end is grounded; The second resistor R5 is connected at one end to the output terminal of the power operational amplifier U5, and at the other end to the connection line between the first resistor R21 and the negative input terminal of the power operational amplifier U5. The first capacitor is connected in parallel with the second resistor.

[0056] The current limiting resistor 10232 includes a third resistor R24 ​​and a fourth resistor R25 (e.g., GL+) connected in parallel on both sides of the output terminal of the power operational amplifier U5 (e.g., CL+ and CL-), for limiting the maximum output current of the power operational amplifier U5 and providing overcurrent protection.

[0057] The filter capacitor 10233 includes: a first capacitor C25 and a second capacitor C26 connected in parallel with the positive terminal of the power operational amplifier U5, and a third capacitor C30 and a fourth capacitor C31 connected in parallel with the negative terminal of the power operational amplifier U5, which are used to filter the external power supply to the positive and negative terminals respectively, so as to avoid the fluctuation of the external power supply affecting the amplified bipolar voltage of the power amplifier output.

[0058] The above solution can effectively protect the power operational amplifier U5 and ensure that the power operational amplifier U5 can normally amplify and output the amplified bipolar voltage.

[0059] In some embodiments, such as Figure 3 As shown, the first overvoltage protection circuit 103 includes: A transistor (MOS, Metal-Oxide-Semiconductor Field-Effect Transistor) circuit is connected to the output of the bidirectional power supply 102 and is configured to transmit bipolar voltage. The first optocoupler circuit U6, connected to the processor 101 and the transistor circuit Q1, is configured to disconnect in response to receiving a first cut-off command from the processor 101, and control the transistor circuit Q1 to turn off, cutting off the transmission of bipolar voltage; or, in response to receiving a first run command from the processor 101, the first optocoupler circuit U6 is turned on, and control the transistor circuit Q1 to turn on, transmitting bipolar voltage.

[0060] In specific implementation, the processor 101 can compare the voltage sampled by the voltage acquisition circuit 105 with the first voltage limit range to control the on / off state of the first optocoupler circuit U6. This allows the processor 101 to promptly send a first cut-off command (e.g., a high-level DO signal) to the first optocoupler circuit U6 after detecting that the sampled voltage exceeds the first voltage limit range, thus disconnecting the first optocoupler circuit U6. This disconnects the external power supply (e.g., a 15V power supply), stopping power supply to the transistor circuit Q1, causing the transistor circuit Q1 to turn off and blocking the transmission of bipolar voltage by the transistor.

[0061] Through the above scheme, by cooperating with the transistor circuit Q1 and the first optocoupler circuit U6, the first optocoupler circuit U6 can block the power supply of the transistor circuit Q1 in a timely manner according to the first cut-off command sent by the processor 101 after detecting that the sampling voltage exceeds the first voltage limit range, thus avoiding damage to the back-end load due to excessive bipolar voltage.

[0062] In some embodiments, transistor circuit Q1 is connected to an external power supply through first optocoupler circuit U6, and is configured such that first optocoupler circuit U6 is turned on to connect external power supply to transistor circuit Q1, turning on transistor circuit Q1 to transmit bipolar voltage; or, it is configured such that first optocoupler circuit U6 is turned off to stop connecting external power supply to transistor circuit Q1, turning off transistor circuit Q1 to cut off bipolar voltage transmission.

[0063] In specific implementation, such as Figure 5As shown, a fifth resistor R7 is connected between pin 1 of the first optocoupler circuit U6 and the DC power supply (e.g., +5V power supply), and pin 2 of the first optocoupler circuit U6 is connected to the processor 101 (e.g., connected to the DO_L pin of the processor 101), thus enabling the reception of control signals from the processor 101. A sixth resistor R6 is connected between the DC power supply and the processor 101 connection line. Pin 4 of the first optocoupler circuit U6 is connected to an external power supply (e.g., power supply L_15V) via a seventh resistor, and pin 3 of the first optocoupler circuit U6 is connected to pin G of the transistor circuit Q1 via an eighth resistor R10. A fifth capacitor C39, a sixth capacitor C29, and a ninth resistor R11 are connected in parallel across the GS pins of the transistor circuit Q1. The fifth capacitor C39 and the sixth capacitor C29 are used for filtering, and the ninth resistor R11 is used for current limiting.

[0064] During normal operation, the processor 101 sends a first operating signal, and the first optocoupler circuit U6 is turned on, allowing the external power supply to be normally connected to the GS pin of the transistor, turning on the transistor and connecting the DS pin of the transistor, so that the bipolar voltage is transmitted normally. When the processor 101 detects that the sampling voltage exceeds the first voltage limit range, it sends a first cut-off command (e.g., a high-level DO signal) to control the first optocoupler circuit U6 to be turned off, so that the external power supply cannot be connected to the transistor, the DS pin of the transistor is turned off, and thus the transmission of bipolar voltage is cut off.

[0065] The above scheme enables the processor 101 to accurately control the switching on and off of the first optocoupler circuit U6, thereby better controlling the switching on and off of the transistor and achieving overvoltage protection for bipolar voltage.

[0066] In some embodiments, such as Figure 3 As shown, the second overvoltage protection circuit 104 includes: The relay circuit U28 (e.g., a solid-state relay) is connected between the first overvoltage protection circuit 103 and the voltage acquisition circuit 105; The detection circuit 1041, connected to the first overvoltage protection circuit 103, is configured to detect whether the bipolar voltage transmitted from the first overvoltage protection circuit 103 exceeds the second voltage limit range, and generate a second cut-off command in response to exceeding the second voltage limit range; or, generate a second operation command in response to being within the second voltage limit range. The second optocoupler circuit U21, connected to the detection circuit 1041 and the relay circuit U28, is configured to disconnect in response to receiving a second cut-off command, and control the relay circuit U28 to disconnect, cutting off the transmission of bipolar voltage; or, in response to receiving a second operation command, the second optocoupler circuit U21 is turned on, and controls the relay circuit U28 to turn on, transmitting bipolar voltage.

[0067] In specific implementation, such as Figure 6 As shown, the positive terminal of the relay circuit U28 can be connected to a DC power supply (e.g., DC28VB) through the tenth resistor R42, thus providing power for the relay to operate. Pin 4 of the second optocoupler circuit U21 is connected to the negative terminal of the relay circuit U28 through resistor R43, and pin 3 of the second optocoupler circuit U21 is grounded. Pin 1 of the second optocoupler circuit U21 is also connected to a DC power supply (e.g., ECF_+5V) through the eleventh resistor R41, the first diode D8, the second diode D7, and the twelfth resistor R40. In this way, the eleventh resistor R41 and the twelfth resistor R40 perform voltage division, and the first diode D8 and the second diode D7 avoid the influence of reverse current.

[0068] The detection circuit 1041 is connected between pin 1 and pin 2 of the second optocoupler circuit U21, and the detection circuit 1041 is also connected to the first overvoltage protection circuit 103 to detect the bipolar voltage transmitted from the first overvoltage protection circuit 103 and control the second optocoupler circuit U21 according to the detection result.

[0069] During normal operation, the detection circuit 1041 detects the bipolar voltage within the second voltage limit range, generates a second operating command, and controls the second optocoupler circuit U21 to turn on, so that the DC power supply can supply power to the relay circuit U28, ensuring that the relay circuit U28 is turned on, and can use the relay circuit U28 to transmit the bipolar voltage from the first overvoltage protection circuit 103 to the voltage acquisition circuit 105, thereby providing bipolar voltage operation for the load.

[0070] If the detection circuit 1041 detects that the bipolar voltage exceeds the second voltage limit range, it generates a second cut-off command to control the second optocoupler circuit U21 to disconnect, so that the DC power supply cannot supply power to the relay circuit U28. The relay circuit U28 disconnects and stops transmitting the bipolar voltage from the first overvoltage protection circuit 103 to the voltage acquisition circuit 105, thereby avoiding damage to the load caused by the excessive bipolar voltage.

[0071] Through the above scheme, the effective cooperation of the detection circuit 1041, the second optocoupler circuit U21 and the relay circuit U28 can effectively protect the bipolar voltage transmitted from the first overvoltage protection circuit 103 from overvoltage, improve the safety of bipolar voltage transmission, and reduce the damage to the load caused by excessive bipolar voltage.

[0072] In some embodiments, such as Figure 3 As shown, the detection circuit 1041 includes: An absolute value circuit 10411 (e.g., dual op-amp U22 and configuration circuit) is connected to a first overvoltage protection circuit 103 and is configured to perform absolute value processing on the bipolar voltage transmitted from the first overvoltage protection circuit 103 to obtain an absolute value voltage. A voltage detection circuit 10412 (e.g., a precision reference source U23 and a configuration circuit) is connected between an absolute value circuit 10411 and a second optocoupler circuit U21. It is configured to acquire the absolute value voltage of the absolute value circuit 10411, detect whether the absolute value voltage exceeds a second voltage limit range, and generate a second cut-off command and send it to the second optocoupler circuit U21 in response to exceeding the second voltage limit range; or, in response to being within the second voltage limit range, generate a second operation command and send it to the second optocoupler circuit U21.

[0073] In specific implementation, such as Figure 6 As shown, the absolute value circuit 10411 includes: Dual op-amp U22; The thirteenth resistor R32 has one end connected to the output terminal of the first overvoltage protection circuit 103, and the other end connected to the negative input pin 2 (e.g., -IN A) of the dual operational amplifier U22. The fourteenth resistor R33 is connected at one end to the other end of the thirteenth resistor R32, and at the other end to the positive input pin 5 (e.g., +IN B) of the dual op-amp U22. The fifteenth resistor R34 is connected at one end to the other end of the thirteenth resistor R32, and at the other end is connected to the positive input pin 5 (e.g., +IN B) of the dual op-amp U22 through the third diode D10 and the fourth diode D9. The sixteenth resistor R35 is connected at one end to the output pin 7 (e.g., OUT B) of the dual op-amp U22 and at the other end to the negative input pin 6 (e.g., -IN B) of the dual op-amp U22. The seventeenth resistor R36 has one end connected to the other end of the sixteenth resistor R35, and the other end connected to the other end of the fifteenth resistor R34.

[0074] Among them, the thirteenth resistor R32 to the seventeenth resistor R36 are all protective resistors, and the third diode D10 and the fourth diode D9 utilize the unidirectional conduction performance to avoid the influence of reverse current.

[0075] The voltage detection circuit 10412 includes: Precision reference source U23 has its pin 1 (e.g., VATHODE) connected to the twelfth resistor R40; pin 2 (e.g., REF) connected to the output pin 7 (e.g., OUT B) of the dual operational amplifier U22 via the eighteenth resistor R38 and the nineteenth resistor R37; pin 2 (e.g., REF) is also grounded via the twentieth resistor R39; and pin 3 (e.g., ANODE) ​​is grounded. The eighteenth resistor R38, the nineteenth resistor R37, and the twentieth resistor R39 are all voltage divider protection resistors.

[0076] Through the above scheme, the absolute value circuit 10411 can be used to perform absolute value processing on the bipolar voltage transmitted from the first overvoltage protection circuit 103, ensuring that the voltage transmitted to the voltage detection circuit 10412 is greater than or equal to 0V, avoiding the problem of difficulty in handling negative voltage. In this way, the obtained positive absolute value voltage can be output to the voltage detection circuit 10412, so that the voltage detection circuit 10412 can accurately detect the absolute value circuit 10411. If the absolute value voltage exceeds the second voltage limit range, a second cut-off command will be generated, and the second optocoupler circuit U21 will be disconnected in time, so that the DC power supply cannot supply power to the relay circuit U28. The relay circuit U28 will disconnect and stop transmitting the bipolar voltage from the first overvoltage protection circuit 103 to the voltage acquisition circuit 105, thereby avoiding damage to the load by excessive bipolar voltage.

[0077] It should be noted that the above description describes some embodiments of this application. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in a different order than that shown in the above embodiments and still achieve the desired result. Furthermore, the processes depicted in the drawings do not necessarily require a specific or sequential order to achieve the desired result. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0078] Based on the same concept, this application also provides an overvoltage protection method, applicable to the overvoltage protection device of any of the above embodiments, such as... Figure 7 As shown, the method includes: Step 201: Using a bidirectional power supply, output a bipolar voltage to the first overvoltage protection circuit; Step 202: In response to determining that the sampled voltage of the voltage acquisition circuit exceeds the first voltage limit range, the processor determines a first cut-off command to instruct the first overvoltage protection circuit to cut off the transmission of bipolar voltage according to the first cut-off command; or, in response to determining that the sampled voltage of the voltage acquisition circuit is within the first voltage limit range, the processor determines a first run command to transmit the bipolar voltage to the second overvoltage protection circuit according to the first run command. Step 203: Using the second overvoltage protection circuit, the bipolar voltage transmitted from the first overvoltage protection circuit is detected. In response to the bipolar voltage exceeding the second voltage limit range, the transmission of the bipolar voltage is cut off, or in response to the bipolar voltage being within the second voltage limit range, the bipolar voltage is transmitted to the voltage acquisition circuit. Step 204: Use the voltage acquisition circuit to provide a bipolar voltage to the load.

[0079] The above scheme allows the processor to detect the voltage sampled by the voltage acquisition circuit. If the voltage exceeds the first voltage limit, a first cut-off command is sent to the first overvoltage protection circuit to cut off the transmission of the bipolar voltage. Furthermore, to improve the accuracy of overvoltage protection for the bipolar voltage, a second overvoltage protection circuit is used to detect the bipolar voltage transmitted from the first overvoltage protection circuit. If the voltage exceeds the second voltage limit, the transmission of the bipolar voltage from the second overvoltage protection circuit is disconnected. This ensures that excessively high bipolar voltages are not transmitted to the load through the voltage acquisition circuit. With the dual overvoltage protection of the first and second overvoltage protection circuits, the load is guaranteed to always operate within the normal voltage range.

[0080] The methods described above are implemented using the apparatus in any of the foregoing embodiments and have the beneficial effects of the corresponding apparatus embodiments, which will not be repeated here.

[0081] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of this application (including the claims) is limited to these examples; within the framework of this application, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of the embodiments of this application as described above, which are not provided in the details for the sake of brevity.

[0082] Additionally, to simplify the description and discussion, and to avoid obscuring the embodiments of this application, the well-known power / ground connections to integrated circuit (IC) chips and other components may or may not be shown in the provided drawings. Furthermore, the apparatus may be illustrated in block diagram form to avoid obscuring the embodiments of this application, and this also takes into account the fact that the details of the implementation of these block diagram apparatuses are highly dependent on the platform on which the embodiments of this application will be implemented (i.e., these details should be fully understood by those skilled in the art). While specific details (e.g., circuits) have been set forth to describe exemplary embodiments of this application, it will be apparent to those skilled in the art that the embodiments of this application can be implemented without these specific details or with variations thereof. Therefore, these descriptions should be considered illustrative rather than restrictive.

[0083] Although this application has been described in conjunction with specific embodiments thereof, many substitutions, modifications, and variations of these embodiments will be apparent to those skilled in the art from the foregoing description. For example, other memory architectures (e.g., DRAM) may be used with the embodiments discussed.

[0084] The embodiments of this application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the embodiments of this application should be included within the protection scope of this application.

Claims

1. An overvoltage protection device, characterized in that, include: The processor, bidirectional power supply, first overvoltage protection circuit, second overvoltage protection circuit, and voltage acquisition circuit are connected in sequence. The processor is also connected to the voltage acquisition circuit and the first overvoltage protection circuit, and is configured to receive the sampled voltage from the voltage acquisition circuit, and in response to the sampled voltage exceeding the first voltage limit range, issue a first cut-off command to the first overvoltage protection circuit. The bidirectional power supply is configured to output a bipolar voltage to the first overvoltage protection circuit; The first overvoltage protection circuit is configured to transmit the bipolar voltage to the second overvoltage protection circuit, and to cut off the transmission of the bipolar voltage in response to receiving the first cut-off command. The second overvoltage protection circuit is configured to transmit the bipolar voltage to the voltage acquisition circuit, and to cut off the transmission of the bipolar voltage in response to the bipolar voltage exceeding the second voltage limit range. The voltage acquisition circuit is connected to the load and is configured to transmit the bipolar voltage to the load, and simultaneously sample the bipolar voltage to determine the sampled voltage and send it to the processor.

2. The overvoltage protection device according to claim 1, characterized in that, The bidirectional power supply includes: A digital-to-analog converter, connected to the processor, is configured to perform digital-to-analog conversion on digital signals sent by the processor to control the bipolar voltage transmission, and to sample the output of the bipolar voltage and send the sampled output voltage to the processor. The processor is configured to detect the output sampling voltage from the digital-to-analog converter (DAC), and in response to the output sampling voltage exceeding a third voltage limit range, send a stop command to the DAC to stop the bipolar voltage transmission via the DAC.

3. The overvoltage protection device according to claim 2, characterized in that, The bidirectional power supply also includes: A spike voltage protection circuit, connected to the digital-to-analog converter, is configured to regulate the bipolar voltage transmitted by the digital-to-analog converter to obtain a regulated bipolar voltage. The power amplifier output circuit is connected to the peak voltage protection circuit and the first overvoltage protection circuit respectively, and is configured to amplify the bipolar voltage after the voltage regulation control, and send the amplified bipolar voltage to the first overvoltage protection circuit.

4. The overvoltage protection device according to claim 3, characterized in that, The peak voltage protection circuit includes: The first voltage divider resistor, with one end connected to the digital-to-analog converter and the other end connected to the power amplifier output circuit, is configured to divide the bipolar voltage controlled and transmitted by the digital-to-analog converter. The second voltage divider resistor has one end connected to the connection between the first voltage divider resistor and the power amplifier output circuit, and the other end grounded. It is configured to divide the bipolar voltage controlled and transmitted by the digital-to-analog converter. A bidirectional voltage regulator circuit, with one end connected to the connection between the first voltage divider resistor and the power amplifier output circuit, and the other end grounded, is configured to turn on after determining that the bipolar voltage exceeds the set voltage regulation range, so that the current flowing through the first voltage divider resistor increases, the voltage division of the first voltage divider resistor increases, and the bipolar voltage after voltage regulation is transmitted to the power amplifier output circuit.

5. The overvoltage protection device according to claim 3, characterized in that, The power amplifier output circuit includes: The power operational amplifier, with its positive input terminal connected to the spike voltage protection circuit, is configured to amplify the power of the regulated bipolar voltage. A feedback circuit, located between the negative input terminal and the output terminal of the power operational amplifier, is configured to feed back the amplified bipolar voltage to the power operational amplifier for power amplification adjustment. A current-limiting resistor is disposed at the output terminal of the power operational amplifier and is configured to limit the maximum output current of the power operational amplifier. The filter capacitor, connected to the positive and negative terminals of the power operational amplifier, is configured to filter the power supply of the power operational amplifier.

6. The overvoltage protection device according to claim 1, characterized in that, The first overvoltage protection circuit includes: A transistor circuit, connected to the output of the bidirectional power supply, is configured to transmit the bipolar voltage; A first optocoupler circuit, connected to the processor and the transistor circuit, is configured to, in response to receiving a first cut-off command from the processor, disconnect the first optocoupler circuit and control the transistor circuit to turn off, cutting off the transmission of the bipolar voltage; or, in response to receiving a first run command from the processor, connect the first optocoupler circuit and control the transistor circuit to turn on, transmitting the bipolar voltage.

7. The overvoltage protection device according to claim 6, characterized in that, The transistor circuit is connected to an external power supply through the first optocoupler circuit and is configured such that the first optocoupler circuit is turned on to connect the external power supply to the transistor circuit, thereby turning on the transistor circuit and transmitting the bipolar voltage; or, it is configured such that the first optocoupler circuit is turned off to disconnect the external power supply, thereby turning off the transistor circuit and cutting off the transmission of the bipolar voltage.

8. The overvoltage protection device according to claim 1, characterized in that, The second overvoltage protection circuit includes: A relay circuit is connected between the first overvoltage protection circuit and the voltage acquisition circuit; The detection circuit, connected to the first overvoltage protection circuit, is configured to detect whether the bipolar voltage transmitted from the first overvoltage protection circuit exceeds the second voltage limit range, and generate a second cut-off command in response to exceeding the second voltage limit range; or, generate a second operation command in response to being within the second voltage limit range. The second optocoupler circuit, connected to the detection circuit and the relay circuit, is configured to, in response to receiving the second cut-off command, disconnect the second optocoupler circuit and control the relay circuit to disconnect, cutting off the transmission of the bipolar voltage; or, in response to receiving the second operation command, connect the second optocoupler circuit and control the relay circuit to connect, transmitting the bipolar voltage.

9. The overvoltage protection device according to claim 8, characterized in that, The detection circuit includes: An absolute value circuit, connected to the first overvoltage protection circuit, is configured to perform absolute value processing on the bipolar voltage transmitted from the first overvoltage protection circuit to obtain an absolute value voltage. A voltage detection circuit, connected between the absolute value circuit and the second optocoupler circuit, is configured to acquire the absolute value voltage of the absolute value circuit, detect whether the absolute value voltage exceeds the second voltage limit range, and generate a second cut-off command and send it to the second optocoupler circuit in response to exceeding the second voltage limit range; or, generate a second operation command and send it to the second optocoupler circuit in response to being within the second voltage limit range.

10. An overvoltage protection method, characterized in that, The method, applied to the overvoltage protection device according to any one of claims 1 to 9, comprises: Using a bidirectional power supply, a bipolar voltage is output to the first overvoltage protection circuit; In response to determining that the voltage sampling voltage of the voltage acquisition circuit exceeds a first voltage limit range, the processor determines a first cut-off command to instruct the first overvoltage protection circuit to cut off the transmission of the bipolar voltage according to the first cut-off command; or, in response to determining that the voltage sampling voltage of the voltage acquisition circuit is within the first voltage limit range, the processor determines a first run command to transmit the bipolar voltage to the second overvoltage protection circuit according to the first run command. The bipolar voltage transmitted from the first overvoltage protection circuit is detected using the second overvoltage protection circuit. In response to the bipolar voltage exceeding the second voltage limit range, the transmission of the bipolar voltage is cut off, or in response to the bipolar voltage being within the second voltage limit range, the bipolar voltage is transmitted to the voltage acquisition circuit. The voltage acquisition circuit is used to provide the bipolar voltage to the load.

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