Overcurrent protection method and overcurrent protection circuit

Abstract

The embodiment of the present application discloses an overcurrent protection method and an overcurrent protection circuit, the method comprising: a sampling module acquires a current signal connected to the overcurrent protection circuit; a logic processing module determines a power control signal of a load corresponding to the overcurrent protection circuit, and a dynamic reference voltage generator determines a corresponding dynamic reference voltage signal based on the power control signal; the logic processing module determines that when an overcurrent protection condition is reached according to the current value signal and the dynamic reference voltage signal, the switch module is controlled to disconnect to perform overcurrent protection on the load. The dynamic reference voltage generator determines the corresponding dynamic reference voltage signal based on the power control signal, so that the dynamic reference voltage changes in real time with the change of the power control signal, thereby achieving the effect of dynamically adjusting the reference voltage. At the same time, the overcurrent protection circuit composed of the logic processing module, the dynamic reference voltage generator and the switch module satisfies the overcurrent protection of the protection circuit under the premise of low cost and high reliability.

Description

Technical Field

[0001] The present application relates to the field of circuit technology, and in particular to an overcurrent protection method and an overcurrent protection circuit. Background Art

[0002] Overcurrent protection refers to a protection method that activates the protection device when the current in the protected circuit exceeds the preset maximum value. When the current flowing through the protected circuit exceeds a certain preset value, the protection device is activated and cuts off the current circuit. In the power circuit of high-power electrical devices, overcurrent protection function is usually added.

[0003] In the related art, overcurrent protection methods include pure hardware overcurrent protection methods and overcurrent protection methods with software monitoring. However, the pure hardware overcurrent protection method can only pre-set a current protection value and cannot meet the overcurrent protection requirements under different working conditions; the overcurrent protection method with software monitoring increases the cost and depends on the reliability of the software.

[0004] Application Contents

[0005] The embodiments of the present application hope to provide an overcurrent protection method and an overcurrent protection circuit, which can achieve overcurrent protection for the protection circuit under the premise of meeting low cost and high reliability.

[0006] The technical solution of this application is implemented as follows:

[0007] The embodiment of the present application provides an overcurrent protection method, which is applied to an overcurrent protection circuit. The overcurrent protection circuit includes a sampling module, a logic processing module, a dynamic reference voltage generator and a switch module, including:

[0008] The sampling module acquires a current signal connected to the overcurrent protection circuit;

[0009] The logic processing module determines a power control signal of a load corresponding to the overcurrent protection circuit, and the dynamic reference voltage generator determines a corresponding dynamic reference voltage signal based on the power control signal;

[0010] When the logic processing module determines that an overcurrent protection condition is reached according to the current value signal and the dynamic reference voltage signal, the logic processing module controls the switch module to disconnect to perform overcurrent protection on the load.

[0011] The embodiment of the present application provides an overcurrent protection circuit, comprising: a sampling module, a logic processing module, a dynamic reference voltage generator and a switch module, wherein the input end of the sampling module is used to sample the input current of the power input end, the output end of the sampling module is connected to the logic processing module, the output end of the logic processing module is connected to the control end of the switch module, and the output end of the switch module is connected to the overcurrent protection circuit and the power input end;

[0012] The sampling module is used to collect the current signal connected to the overcurrent protection circuit;

[0013] The logic processing module is used to determine the power control signal of the load corresponding to the overcurrent protection circuit;

[0014] The dynamic reference voltage generator is used to determine a corresponding dynamic reference voltage signal based on the power control signal;

[0015] The logic processing module is further used to control the switch module to disconnect to perform overcurrent protection on the load when determining that an overcurrent protection condition is met based on the current value signal and the dynamic reference voltage signal.

[0016] An embodiment of the present application provides a computer-readable storage medium storing executable instructions, characterized in that when the executable instructions are executed by a processor, the overcurrent protection method provided by the embodiment of the present application is implemented.

[0017] The embodiment of the present application provides an overcurrent protection method and an overcurrent protection circuit. When implemented, first, the sampling module obtains the current signal connected to the overcurrent protection circuit; then, the logic processing module determines the power control signal of the load corresponding to the overcurrent protection circuit, and the dynamic reference voltage generator determines the corresponding dynamic reference voltage signal based on the power control signal; finally, the logic processing module determines that when the overcurrent protection condition is met based on the current value signal and the dynamic reference voltage signal, the switch module is controlled to disconnect to perform overcurrent protection on the load. In this way, the dynamic reference voltage generator determines the corresponding dynamic reference voltage signal based on the power control signal, so that the dynamic reference voltage changes in real time with the change of the power control signal, thereby achieving the effect of dynamically adjusting the reference voltage. At the same time, the overcurrent protection circuit composed of the logic processing module, the dynamic reference voltage generator and the switch module satisfies the overcurrent protection of the protection circuit under the premise of low cost and high reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A pure hardware overcurrent protection solution provided in the prior art;

[0019] Figure 2 A solution with software monitoring provided in the prior art;

[0020] Figure 3 A flow chart of an overcurrent protection method is provided for an embodiment of the present application;

[0021] Figure 4 A schematic diagram of the structure of an overcurrent protection circuit provided in an embodiment of the present application;

[0022] Figure 5 A schematic diagram of the structure of another overcurrent protection circuit provided in an embodiment of the present application;

[0023] Figure 6 A schematic diagram of the structure of another overcurrent protection circuit provided in an embodiment of the present application;

[0024] Figure 7 A flow chart of a dynamic threshold overcurrent protection method provided in an embodiment of the present application. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings. The described embodiments should not be regarded as limiting the present application. All other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of this application.

[0026] In the following description, reference is made to “some embodiments\other embodiments”, which describe a subset of all possible embodiments, but it can be understood that “some embodiments\other embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0027] In the following description, the terms "first\second" involved are merely used to distinguish similar objects and do not represent a specific ordering of the objects. It can be understood that "first\second" can be interchanged with a specific order or sequence where permitted, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein.

[0028] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used in this application are only for the purpose of describing the embodiments of this application and are not intended to limit this application.

[0029] In the related art, the overcurrent protection circuit usually includes several elements, including a power supply, a switching device, a load, a power control device, a current sensor, a logic control unit, a comparator, and a reference voltage source. The power control device generally includes an electronic switch or an array of electronic switches, which can convert a pulse width modulation signal (PWM) or other digital signal into an actual power output device. The reference voltage source is mainly provided to a stable and accurate power supply for use by the comparator. The output value of the reference voltage source determines the preset value of the overcurrent protection point. The current value signal output by the current sensor is compared with the output value of the reference voltage source. If the current value signal is lower than the reference voltage, no protection occurs. If the current value signal is greater than the reference voltage, it means that the current is too large, and the protection is triggered.

[0030] Figure 1 The figure shows a pure hardware overcurrent protection solution provided in the prior art, which can only preset a current protection value. In some applications, the entire power circuit has a large dynamic range when working. For example, in normal operation, the minimum current is 1A under certain working conditions, and the maximum current is 100A under other working conditions. At this time, the preset overcurrent protection point can only be set to more than 100A. If the system is abnormal under low current conditions and generates an abnormal current within 100A, but does not reach the preset protection value, the circuit will not be cut off, which may cause serious consequences such as circuit burning.

[0031] Figure 2 The figure shows a solution with software monitoring provided in the prior art. Figure 1 The pure hardware overcurrent protection solution in the system adds an analog-to-digital converter (ADC). The ADC can also be included in the logic processing unit to convert the current value signal into a digital signal and send it to the logic processing unit for comparison with the preset value. Then, by judging the comparison result, the protection signal is output, and the final protection signal is generated after the logical relationship with the output of the comparator. At this time, the preset value of the protection point in the software can be changed dynamically. The first disadvantage of this method is that it increases the cost. ADC chips or programmable devices with ADC functions are usually more expensive; the second disadvantage is that it depends on the reliability of the software. If there is a bug in the software or the control chip is disturbed and works abnormally, the software runs away, etc., the protection may not be executed normally.

[0032] The embodiment of the present application provides an overcurrent protection method, which can achieve overcurrent protection for a protection circuit under the premise of meeting low cost and high reliability.

[0033] The following will describe the overcurrent method provided by the embodiment of the present application. Figure 3The figure is a flow chart of an overcurrent protection method provided by an embodiment of the present application, which is applied to Figure 4 The overcurrent protection circuit shown, Figure 4 The overcurrent protection circuit 1 includes a sampling module 11, a logic processing module 12, a dynamic reference voltage generator 13 and a switch module 14. The overcurrent protection method provided in the embodiment of the present application includes the following steps:

[0034] S101. A sampling module obtains a current signal connected to an overcurrent protection circuit.

[0035] It should be noted that the sampling module can be a current sensor, such as a Hall current sensor, a sampling resistor, a current transformer, or any other device that can convert a current signal. The current signal connected to the overcurrent protection circuit can be the current connected to the overcurrent protection circuit. In practice, the sampling module can convert the current signal to obtain a corresponding voltage signal, or directly output the collected current signal without converting the current signal. The current signal involved in the overcurrent protection circuit can be collected by the sampling module.

[0036] S102: The logic processing module determines a power control signal of a load corresponding to the overcurrent protection circuit, and the dynamic reference voltage generator determines a corresponding dynamic reference voltage signal based on the power control signal.

[0037] In some embodiments, the logic processing module may include programmable devices such as MCU, MCU, DSP, FPGA, etc. The power control signal may be a PWM signal, which is used to adjust the power consumed by the load corresponding to the overcurrent protection circuit. In practice, the duty cycle of the PWM signal can be adjusted according to the power required to be consumed by the load corresponding to the overcurrent protection circuit to achieve the adjustment of the voltage size connected to the load, and then achieve the adjustment of the power required to consume by the load.

[0038] The dynamic reference voltage generator can be used to generate a dynamic reference voltage. The dynamic reference voltage signal can be a reference voltage signal that changes dynamically. The dynamic reference voltage signal can change according to the change of the power control signal. Different power control signals can be PWM signals with different duty cycles. For example, the same electrical device has different functions or different working conditions. The corresponding load in the electrical device needs to consume different power. The power control signal determined by the logic processing module is different, and the reference voltage signal determined according to the different power control signals is different, that is, the reference voltage signal can change dynamically according to the change of the power control signal.

[0039] S103: When the logic processing module determines that the overcurrent protection condition is met according to the current signal and the dynamic reference voltage signal, the logic processing module controls the switch module to disconnect to perform overcurrent protection on the load.

[0040] In some embodiments, the switch module can be a switch device such as a relay, a circuit breaker, a contactor, a transistor, etc. When implementing this step, the current signal collected by the sampling module can be first converted into a voltage signal, and then based on the voltage signal and the dynamic reference voltage signal, it is determined whether the overcurrent protection condition is met. When implementing, the determined voltage signal and the dynamic reference voltage signal can be directly compared to determine whether the overcurrent protection condition is met, wherein when the voltage value of the voltage signal is greater than or equal to the voltage value of the dynamic reference voltage signal, it is determined that the overcurrent protection condition is met, and when the voltage value of the voltage signal is less than the voltage value of the dynamic reference voltage signal, it is determined that the overcurrent protection condition is not met. In some embodiments, a preset difference voltage value can also be obtained, and then a target reference voltage value is determined based on the voltage value of the dynamic reference voltage signal and the preset voltage value, and then the determined voltage value and the target reference voltage value are compared to determine whether the overcurrent protection condition is met.

[0041] When it is determined that the overcurrent protection condition is met, the switch module can be controlled to disconnect to provide overcurrent protection for the load, thereby preventing the current connected to the load from being too large and burning the electrical equipment corresponding to the load.

[0042] In the embodiment of the present application, the current signal connected to the overcurrent protection circuit is obtained through the sampling module; the logic processing module determines the power control signal of the load corresponding to the overcurrent protection circuit, and the dynamic reference voltage generator determines the corresponding dynamic reference voltage signal based on the power control signal; the logic processing module determines that when the overcurrent protection condition is met based on the current value signal and the dynamic reference voltage signal, the switch module is controlled to disconnect to protect the load from overcurrent. In this way, the dynamic reference voltage generator determines the corresponding dynamic reference voltage signal based on the power control signal, so that the dynamic reference voltage changes in real time with the change of the power control signal, thereby achieving the effect of dynamically adjusting the reference voltage. At the same time, the overcurrent protection circuit composed of the logic processing module, the dynamic reference voltage generator and the switch module satisfies the overcurrent protection of the protection circuit under the premise of low cost and high reliability.

[0043] In some embodiments of the present application, step S102 "the logic processing module determines the power control signal corresponding to the overcurrent protection circuit, and the dynamic reference voltage generator determines the corresponding dynamic reference voltage signal based on the power control signal" can be implemented by the following steps S1021A to S1023A, and each step is described in detail below.

[0044] S1021A, the logic processing module obtains the working power of the load corresponding to the overcurrent protection circuit.

[0045] In some embodiments, the working power of the load corresponding to the overcurrent protection circuit may be the power required to be consumed by the load, such as the power consumed by the corresponding load when the electrical equipment is working normally. The power consumed by the load may be different under different working conditions of the electrical equipment. For example, the power required to be consumed by the corresponding load of the oven is different at different set temperatures. In practice, the logic processing module can obtain the working power of the corresponding load of the electrical equipment under different working conditions.

[0046] S1022A, the logic processing module determines a power control signal based on the operating power and the power supply voltage connected to the overcurrent protection circuit.

[0047] In some embodiments, the power control signal is used to control the electrical signal (such as a voltage signal) connected to the overcurrent protection circuit to reach the power consumed by the load. According to the connected overcurrent protection circuit, the power supply voltage and the working power of the load, the power control signal required to reach the working power of the load can be determined. In practice, PWM modulation can be performed on the power supply voltage signal connected to the current protection circuit. For example, under a certain working condition of the electrical equipment, the working power required by the load is P, the voltage connected to the overcurrent protection circuit is U1, and the resistance value corresponding to the load is R. According to the formula P=U 2 / R, the actual voltage required by the load is calculated as U2, thereby determining the duty cycle of the PWM signal to modulate U1 to U2. For example, the voltage U1 connected to the overcurrent protection circuit is 200 volts (V), and the voltage U2 corresponding to the working power of the load is calculated to be 100V, then it can be determined that the duty cycle corresponding to the PWM signal is 50%.

[0048] S1023A: The dynamic reference voltage generator integrates the power control signal to obtain a dynamic reference voltage signal corresponding to the power control signal.

[0049] In some embodiments, the dynamic reference voltage generator may include an analog integrator to integrate the power control signal to obtain a dynamic reference voltage signal corresponding to the power control signal. Since the power control signal can control the voltage of the load to achieve power control of the load, the dynamic reference voltage signal obtained after integrating the power control signal is associated with the voltage corresponding to the working power of the load. Using the dynamic reference voltage signal as a reference voltage for overcurrent protection can ensure the normal operation of the load.

[0050] It can be understood that in the embodiment of the present application, after the logic processing module obtains the working power of the load corresponding to the overcurrent protection circuit, it determines the power control signal according to the working power and the power supply voltage connected to the overcurrent protection circuit, and the dynamic reference voltage generator integrates the power control signal to obtain a dynamic reference voltage signal corresponding to the power control signal, so that the dynamic reference voltage will change in real time with the change of the power control signal, thereby achieving the effect of dynamically adjusting the reference voltage.

[0051] In some embodiments of the present application, step S103 "when the logic processing module determines, based on the current signal and the dynamic reference voltage signal, that the overcurrent protection condition is met, the control switch module is disconnected to protect the load from overcurrent" can be implemented through the following steps S1031 to S1034, and each step is described in detail below.

[0052] S1031. The logic processing module obtains a preset voltage signal.

[0053] It should be noted that the preset voltage signal can be a voltage value pre-set in the logic processing module. For example, the preset voltage signal can be 1V, 2V, etc. The preset voltage signal can be a compensation signal for the error generated by the acquisition module during the current signal acquisition process or the error generated by the logic processing module during the integration of the power control signal. It can be set by relevant technical personnel in the logic processing module (for example, in the software program).

[0054] 1032. The dynamic reference voltage generator determines a target reference voltage signal based on the dynamic reference voltage signal and the preset voltage signal.

[0055] In some embodiments, the target reference voltage signal may be a reference voltage signal obtained by compensating the dynamic reference voltage signal based on the preset reference voltage signal. The dynamic reference voltage may include an adder. In practice, the adder in the dynamic reference voltage may be used to implement the summation operation of the preset reference voltage signal and the preset reference voltage signal to obtain the target reference voltage signal. For example, if the dynamic reference voltage signal and the preset voltage signal are 120V and 1V respectively, the target reference voltage determined thereby is 121V.

[0056] 1033. The logic processing module determines a voltage signal corresponding to the current signal, compares the target reference voltage signal with the voltage signal, and obtains a first overcurrent protection signal.

[0057] In some embodiments, the logic processing module can convert the current signal collected by the sampling module into a corresponding voltage signal; in other embodiments, the current signal collected by the sampling module can also be converted from current to voltage by the sampling module to obtain a voltage signal corresponding to the current signal.

[0058] After comparing the target reference voltage signal and the voltage signal, a corresponding comparison result, i.e., a first overcurrent protection signal, can be obtained. The first overcurrent protection signal can indicate the magnitude relationship between the target reference voltage and the voltage signal corresponding to the current signal. When the target reference voltage signal is greater than or equal to the voltage signal corresponding to the current signal, the first overcurrent protection signal is a low-level signal, indicating that the current signal is not overcurrent and overcurrent protection does not need to be performed; when the target reference voltage signal is less than the voltage signal corresponding to the current signal, the first overcurrent protection signal is a high-level signal, indicating that the current signal is overcurrent and overcurrent protection needs to be performed.

[0059] 1034. The logic processing module determines, based on the enable signal of the overcurrent protection function and the first overcurrent protection signal, that when an overcurrent protection condition is met, the logic processing module controls the switch module to disconnect to perform overcurrent protection on the load.

[0060] The enable signal of the overcurrent protection function can control the implementation of the overcurrent protection function. The enable signal can be a high-level signal or a low-level signal. When the enable signal is a high-level signal, it indicates that the overcurrent protection can be performed; when the enable signal is a low-level signal, it indicates that the overcurrent protection is not performed. The logic processing module can determine a final overcurrent protection judgment result based on the enable signal of the overcurrent protection function and the first overcurrent protection signal, that is, whether the overcurrent protection condition is met. When it is determined that the overcurrent protection condition is met, the control switch module is disconnected to achieve overcurrent protection for the load.

[0061] In some embodiments, when the enable signal is a high-level signal and the first overcurrent protection signal is a low-level signal, it is determined that the overcurrent protection condition is not met and the overcurrent protection of the load is not triggered; when the enable signal is a low-level signal and the first overcurrent protection signal is a low-level signal, it is determined that the overcurrent protection condition is not met and the overcurrent protection of the load is not triggered; when the first overcurrent protection signal is a low-level signal and the first overcurrent protection signal is a low-level signal, it is determined that the overcurrent protection condition is not met and the overcurrent protection of the load is not triggered.

[0062] In some embodiments of the present application, the above-mentioned step S1034 "the logic processing module determines that when the overcurrent protection condition is met based on the overcurrent protection enable signal and the first overcurrent protection signal, the control switch module is disconnected to perform overcurrent protection on the load" can be implemented by the following steps S201 and S202.

[0063] S201. If the enable signal is a high level signal and the first overcurrent protection signal is a high level signal, it is determined that an overcurrent protection condition is met.

[0064] When the enable signal based on the overcurrent protection function is a high-level signal, it means that the overcurrent protection function can be executed, and the first overcurrent protection signal is a high-level signal, indicating that the current signal exceeds the set maximum current value (corresponding to the target reference voltage signal) and overcurrent protection needs to be executed. When the enable signal and the first overcurrent protection signal are both high-level signals, it means that the overcurrent protection condition has been met.

[0065] S202 . Based on the high-level signal, the switch module is controlled to be disconnected to cut off the overcurrent protection circuit and trigger overcurrent protection for the load.

[0066] When the enable signal and the first overcurrent protection signal are both high-level signals, the logic processing module can control the switch corresponding to the switch module to disconnect based on the high-level signal, cut off the overcurrent protection circuit, and achieve overcurrent protection for the load.

[0067] In some embodiments of the present application, the above-mentioned step S102 "the logic processing module determines, based on the current value signal and the dynamic reference voltage signal, that when the overcurrent protection condition is met, the control switch is disconnected to protect the load from overcurrent" can be implemented not only through the above-mentioned steps S1021A to S1023A, but also through the following steps S1021B to S1024B.

[0068] S1021B, the logic processing module obtains a preset voltage signal.

[0069] It should be noted that the preset voltage signal can be a voltage value pre-set in the logic processing module. For example, the preset voltage signal can be -1V, 1V, 2V, etc. The preset voltage signal can be a compensation signal for the error generated by the acquisition module during the current signal acquisition process or the error generated by the logic processing module during the integration of the power control signal. It can be set by relevant technical personnel in the logic processing module (for example, in the software program).

[0070] S1022B, the logic processing module determines the access voltage signal corresponding to the current signal, and determines a difference voltage signal between the access voltage signal and the preset voltage signal.

[0071] The access voltage signal corresponding to the current signal may be a voltage signal obtained by performing current-to-voltage conversion on the current signal, and the difference voltage signal between the access voltage signal and the preset voltage signal may be obtained by subtracting the access voltage signal from the preset reference voltage signal.

[0072] S1023B: The logic processing module compares the difference voltage signal with the dynamic reference voltage signal to obtain a second overcurrent protection signal.

[0073] After comparing the difference voltage signal and the dynamic reference voltage signal, a corresponding comparison result, i.e., a second overcurrent protection signal, can be obtained. The second overcurrent protection signal can indicate the magnitude relationship between the difference voltage signal and the dynamic reference voltage signal. When the difference voltage signal is greater than the dynamic reference voltage signal, the second overcurrent protection signal is a high-level signal, indicating that the current signal is overcurrent and overcurrent protection needs to be performed; when the difference voltage signal is less than or equal to the dynamic reference voltage signal, the second overcurrent protection signal is a low-level signal, indicating that the current signal is not overcurrent and overcurrent protection does not need to be performed.

[0074] S1024B: The logic processing module determines that when an overcurrent protection condition is met based on the enable signal of the overcurrent protection function and the second overcurrent protection signal, the logic processing module controls the switch module to disconnect to perform overcurrent protection on the load.

[0075] The enable signal of the overcurrent protection function can control the implementation of the overcurrent protection function. The enable signal can be a high-level signal or a low-level signal. When the enable signal is a high-level signal, it indicates that the overcurrent protection can be performed; when the enable signal is a low-level signal, it indicates that the overcurrent protection is not performed. Based on the enable signal of the overcurrent protection function and the second overcurrent protection signal, the logic processing module can determine a final overcurrent protection judgment result, that is, whether the overcurrent protection condition is met. When it is determined that the overcurrent protection condition is met, the control switch module is disconnected to achieve overcurrent protection for the load.

[0076] In some embodiments, the enable signal is a high-level signal, and the second overcurrent protection signal is a high-level signal, and it is determined that the overcurrent protection condition is met. At this time, the switch module can be controlled to disconnect to cut off the overcurrent protection circuit and trigger the overcurrent protection of the load; when the enable signal is a high-level signal, and the first overcurrent protection signal is a low-level signal, it is determined that the overcurrent protection condition is not met, and the overcurrent protection of the load is not triggered; when the enable signal is a low-level signal, and the first overcurrent protection signal is a low-level signal, it is determined that the overcurrent protection condition is not met, and the overcurrent protection of the load is not triggered; when the first overcurrent protection signal is a low-level signal, and the first overcurrent protection signal is a low-level signal, it is determined that the overcurrent protection condition is not met, and the overcurrent protection of the load is not triggered.

[0077] In the embodiment of the present application, the current signal connected to the overcurrent protection circuit is obtained through the sampling module; the logic processing module determines the power control signal of the load corresponding to the overcurrent protection circuit, and the dynamic reference voltage generator determines the corresponding dynamic reference voltage signal based on the power control signal; the logic processing module determines that when the overcurrent protection condition is reached according to the current value signal and the dynamic reference voltage signal, the switch module is controlled to disconnect to protect the load from overcurrent. In this way, the dynamic reference voltage generator determines the corresponding dynamic reference voltage signal based on the power control signal, so that the dynamic reference voltage changes in real time with the change of the power control signal, thereby achieving the effect of dynamically adjusting the reference voltage. At the same time, the overcurrent protection circuit composed of the logic processing module, the dynamic reference voltage generator and the switch module satisfies the overcurrent protection of the protection circuit under the premise of low cost and high reliability.

[0078] The present application embodiment provides an overcurrent protection circuit, such as Figure 4 As shown, it is a structural schematic diagram of an overcurrent protection circuit provided in an embodiment of the present application. The overcurrent protection circuit 2 includes: a sampling module 21, a logic processing module 22, a dynamic reference voltage generator 23 and a switch module 24. The input end of the sampling module 21 is connected to an external input current, the first output end of the sampling module 21 is connected to the logic processing module 22, the second output end of the sampling module 21 is connected to the first input end of the switch module 24, the output end of the logic processing module 22 is connected to the second input end of the switch module 24, and the output end of the switch module 24 is connected to the input end of the overcurrent protection circuit corresponding to the load.

[0079] In some embodiments, the sampling module 21 is used to collect the current signal connected to the overcurrent protection circuit. It should be noted that the sampling module 21 can be a current sensor, such as a Hall current sensor, a sampling resistor, a current transformer, or any other device that can convert a current signal. The sampling module 21 can convert the collected current signal to obtain a converted voltage signal.

[0080] In some embodiments, the logic processing module 22 is used to determine the power control signal of the load corresponding to the overcurrent protection circuit. The logic processing module 22 may include a programmable device such as MCU, MCU, DSP, FPGA, etc. The logic processing module 22 may adjust the power consumed by the load corresponding to the overcurrent protection circuit. In practice, the duty cycle of the PWM signal may be adjusted according to the power required to be consumed by the load corresponding to the overcurrent protection circuit, so as to adjust the voltage size connected to the load, thereby adjusting the power required to be consumed by the load.

[0081] In some embodiments, the dynamic reference voltage generator 23 is used to determine the corresponding dynamic reference voltage signal based on the power control signal. The dynamic reference voltage generator 23 can generate a dynamic reference voltage, and the dynamic reference voltage signal can be a reference voltage signal that changes dynamically. According to the power control signal, the dynamic reference voltage generator 23 can generate a dynamic reference voltage signal that changes with the power control signal.

[0082] In some embodiments, the logic processing module 22 is further used to control the switch module 24 to disconnect to protect the load from overcurrent when it is determined that the overcurrent protection condition is reached according to the current value signal and the dynamic reference voltage signal. In some embodiments, the switch module can be a switch device such as a relay, a circuit breaker, a contactor, a transistor, etc. When the logic processing module determines that the overcurrent protection condition is reached according to the current value signal and the dynamic reference voltage signal, the switch module can be controlled to disconnect to protect the load from overcurrent, so as to prevent the current connected to the load from being too large and burning the electrical equipment corresponding to the load.

[0083] In some embodiments of the present application, Figure 5 FIG. 1 is a schematic diagram of another overcurrent protection circuit provided in an embodiment of the present application. Figure 5 As shown, the logic processing module 22 includes a main control module 221 , and the dynamic reference voltage generator 23 includes an analog integrator 231 .

[0084] In some embodiments, the main control module 221 is used to obtain the working power of the load corresponding to the overcurrent protection circuit, and determine the power control signal based on the working power and the power supply voltage connected to the overcurrent protection circuit. The main control module 221 can be a programmable device such as MCU, MCU, DSP, FPGA, etc., and can determine the required power control signal corresponding to the working power of the load when the working power of the load is reached according to the connected overcurrent protection circuit, the power supply voltage and the working power of the load.

[0085] In some embodiments, the analog integrator 231 is used to integrate the power control signal to obtain a dynamic reference voltage signal corresponding to the power control signal. The analog integrator 231 integrates the power control signal to obtain a dynamic reference voltage signal corresponding to the power control signal. Since the power control signal can control the voltage of the load to achieve power control of the load, the dynamic reference voltage signal obtained after integrating the power control signal is associated with the voltage corresponding to the working power of the load, and the dynamic reference voltage signal is used as the reference voltage for overcurrent protection to ensure normal operation of the load.

[0086] In some embodiments, Figure 5As shown, the logic processing module 22 also includes a comparator 222 and a logic judgment unit 223, the output end of the comparator 222 is connected to the first input end of the logic judgment unit 223, the second output end of the main control module 221 is connected to the second input end of the logic judgment unit 223, the second output end of the sampling module 21 is connected to the first input end of the comparator 222, the output end of the dynamic reference voltage generator 23 is connected to the second input end of the comparator 222, the output end of the logic judgment unit 223 is connected to the second input end of the switch module 24, and the dynamic reference voltage generator 23 includes an analog adder 232.

[0087] In some embodiments, the main control module 221 is also used to obtain a preset voltage signal and determine the access voltage signal corresponding to the current signal. The preset voltage signal can be a voltage value preset in the main control module 221. The preset voltage signal can be a compensation signal for the error generated by the acquisition module during the current signal acquisition process or the error generated by the logic processing module during the integration of the power control signal, and can be set by relevant technicians in the main control module 221.

[0088] In some embodiments, the analog adder 232 is used to perform a sum operation on the dynamic reference voltage and the preset voltage signal to determine the target reference voltage signal. The analog adder 232 can use the adder in the dynamic reference voltage to perform a sum operation on the preset reference voltage signal and the preset reference voltage signal to obtain the target reference voltage signal.

[0089] In some embodiments, the comparator 222 is used to compare the target reference voltage signal with the access voltage signal and output a first overcurrent protection signal to convert the current signal collected by the sampling module 21 into a corresponding voltage signal; in other embodiments, the current signal collected by the sampling module can also be converted from current to voltage by the sampling module 21 to obtain a voltage signal corresponding to the current signal.

[0090] In some embodiments, the logic judgment unit 223 is used to determine the first output signal of the logic judgment unit 223 based on the enable signal of the overcurrent protection function and the first overcurrent protection signal. The logic judgment unit 223 can determine a final overcurrent protection judgment result based on the enable signal of the overcurrent protection function and the first overcurrent protection signal, that is, whether the overcurrent protection condition is met. When it is determined that the overcurrent protection condition is met, the switch module 24 is controlled to be disconnected to achieve overcurrent protection for the load.

[0091] In some embodiments, the main control module 221 is used to control the switch module 24 to disconnect to protect the load from overcurrent when it determines that the overcurrent protection condition is met based on the first output signal. When the first output signal is a high-level signal, the main control module 221 controls the switch module 24 to disconnect to cut off the overcurrent protection circuit line to achieve overcurrent protection for the load.

[0092] In some embodiments, when the enable signal is determined to be a high level signal, and the first overcurrent protection signal output by the comparator 222 is a high level signal, and the first output signal of the logic judgment unit 223 is a high level signal, it is determined that the overcurrent protection condition is met.

[0093] In some embodiments of the present application, Figure 6 As shown in FIG. 1 , it is a structural diagram of another overcurrent protection circuit provided in an embodiment of the present application, such as Figure 6 As shown, the logic processing module 22 further includes an analog subtractor 233 , and the analog subtractor 233 is connected to the second output terminal of the sampling module 21 and the first input terminal of the comparator 222 .

[0094] In some embodiments, the analog subtractor 233 is used to determine a difference voltage signal between the access voltage signal and the preset voltage signal. The difference voltage signal between the access voltage signal and the preset voltage signal can be obtained by subtracting the access voltage signal from the preset reference voltage signal, and the analog subtractor 233 can subtract the access voltage signal from the preset voltage signal to obtain the difference voltage signal.

[0095] In some embodiments, the comparator 222 is used to compare the difference voltage signal with the dynamic reference voltage signal and output a second overcurrent protection signal. After the comparator 222 compares the difference voltage signal with the dynamic reference voltage signal, a corresponding comparison result, i.e., an output result of the comparator 222, can be obtained, and the output result can be a low level or a high level.

[0096] In some embodiments, the logic judgment unit 223 is used to determine the second output signal of the logic judgment unit 223 based on the enable signal of the overcurrent protection function and the second overcurrent protection signal. The logic judgment unit 223 can be a logic AND gate, the enable signal of the overcurrent protection function and the second overcurrent protection signal can be used as inputs of the logic judgment unit 223, and the second output signal is the output of the logic judgment unit 223.

[0097] In some embodiments, the main control module 221 is used to control the switch module 24 to disconnect to protect the load from overcurrent when it determines that the overcurrent protection condition is met based on the second output signal. When the output result of the logic judgment unit 223, that is, the second output signal is at a high level, it indicates that the overcurrent protection condition is met. At this time, the switch module 24 is controlled to disconnect to achieve overcurrent protection for the load.

[0098] In the embodiment of the present application, in the overcurrent protection circuit composed of the sampling module, the logic processing module, the dynamic reference voltage generator 23 and the switch module, the sampling module is used to collect the current signal connected to the overcurrent protection circuit; the logic processing module is used to determine the power control signal of the load corresponding to the overcurrent protection circuit; the dynamic reference voltage generator is used to determine the corresponding dynamic reference voltage signal based on the power control signal. The dynamic reference voltage generator determines the corresponding dynamic reference voltage signal based on the power control signal, so that the dynamic reference voltage changes in real time with the change of the power control signal, thereby achieving the effect of dynamically adjusting the reference voltage. At the same time, the overcurrent protection circuit composed of the logic processing module, the dynamic reference voltage generator and the switch module satisfies the overcurrent protection of the protection circuit under the premise of low cost and high reliability.

[0099] The following is an introduction to the implementation process of the embodiments of the present application in actual application scenarios.

[0100] In some embodiments, Figure 7 As shown, it is a flow chart of a dynamic threshold overcurrent protection method provided in an embodiment of the present application. The overcurrent method provided in an embodiment of the present application can be implemented through the following steps S301 to S304. Each step is described in detail below.

[0101] S301. The current sensor (sampling module) obtains a current value signal.

[0102] The current sensor can be any device that can convert current signals, such as a Hall current sensor, a sampling resistor, a current transformer, etc. The current sensor can collect the current signal connected to the overcurrent protection circuit (obtain the current signal connected to the overcurrent protection circuit), and convert the collected current signal to obtain a current signal corresponding to the current signal.

[0103] S302: Determine a dynamic reference voltage signal based on a power control signal for a load.

[0104] It should be noted that the power control signal of the load can be determined by the MCU (logic processing module). The power control signal is determined according to the power of the connected load (the logic processing module determines the power control signal of the load corresponding to the overcurrent protection circuit). The power control signal can be a PWM signal. The dynamic reference voltage generator can integrate the PWM signal (the dynamic reference voltage generator determines the corresponding dynamic reference voltage signal based on the power control signal) to obtain a dynamic reference voltage signal that changes in real time with the changes in the power control signal.

[0105] S303: Determine a voltage signal (target reference voltage signal) corresponding to the overcurrent protection point based on a preset reference voltage source (preset voltage signal) and a dynamic reference voltage signal.

[0106] In some embodiments, the preset reference voltage source may be a voltage margin signal determined by the MCU, which is used to compensate for the error in the process of current sensing to collect the current signal. The preset reference voltage source may be 1V, 2V, etc. The adder in the dynamic generator may be used to sum the preset reference voltage source and the dynamic reference voltage signal to obtain a voltage signal corresponding to the overcurrent protection point (the dynamic reference voltage generator determines the target reference voltage signal based on the dynamic reference voltage signal and the preset voltage signal).

[0107] S304: When it is determined that the overcurrent protection condition is met according to the voltage signal and the current value signal corresponding to the overcurrent protection point, the switch is controlled to be disconnected to implement overcurrent protection for the load.

[0108] In practice, a comparator can be used to compare the voltage signal corresponding to the overcurrent protection point with the voltage signal corresponding to the current value signal, and output a judgment result. Based on the judgment result and the enable signal output from the MCU, the result is input into the logic AND gate to obtain the final output result. The final output result can determine whether the overcurrent protection condition is met. When the output result of the comparator is a high-level signal and the enable signal output from the MCU is also a high-level signal, the overcurrent protection condition is met, and the control switch is disconnected to achieve overcurrent protection for the load.

[0109] In the application embodiment, a current sensor is used to obtain a current value signal; a dynamic reference voltage signal is determined based on a power control signal for the load; a voltage signal corresponding to an overcurrent protection point is determined based on a preset reference voltage and a dynamic reference voltage signal; when it is determined that the overcurrent protection condition is met according to the voltage signal and the current value signal corresponding to the overcurrent protection point, the control switch is disconnected to achieve overcurrent protection for the load, thereby achieving effective protection for the load in the overcurrent protection circuit. At the same time, a pure hardware protection circuit composed of an MCU, a current sensor, a dynamic reference voltage generator, a comparator, and a logic AND gate has the characteristics of low cost and high reliability.

[0110] The embodiment of the present application also provides a computer-readable storage medium storing executable overcurrent protection instructions, which are used to cause the processor to execute and implement the method provided by the embodiment of the present application, for example, the executable overcurrent protection method provided by the embodiment of the present application. Exemplarily, the overcurrent protection method instruction in this embodiment can be stored on a storage medium such as a CD, a hard disk, a USB flash drive, etc. When the program instructions corresponding to an overcurrent protection method in the storage medium are read or executed by an electronic device, the overcurrent protection method described in any of the above embodiments can be implemented.

[0111] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of hardware embodiments, software embodiments, or embodiments in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage and optical storage, etc.) that contain computer-usable program code.

[0112] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0113] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0114] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0115] The above are only preferred embodiments of the present application and are not intended to limit the protection scope of the present application.

Claims

1. An overcurrent protection method, applied to an overcurrent protection circuit, wherein the overcurrent protection circuit comprises a sampling module, a logic processing module, a dynamic reference voltage generator and a switch module, characterized in that: include: The sampling module acquires a current signal connected to the overcurrent protection circuit; The logic processing module determines a power control signal of a load corresponding to the overcurrent protection circuit, and the dynamic reference voltage generator determines a corresponding dynamic reference voltage signal based on the power control signal; When the logic processing module determines that an overcurrent protection condition is reached according to the current signal and the dynamic reference voltage signal, the logic processing module controls the switch module to disconnect to perform overcurrent protection on the load; The logic processing module determines, according to the current signal and the dynamic reference voltage signal, that when an overcurrent protection condition is reached, controls the switch to be disconnected to perform overcurrent protection on the load, including: The logic processing module obtains a preset voltage signal; The logic processing module determines the access voltage signal corresponding to the current signal, and determines a difference voltage signal between the access voltage signal and the preset voltage signal; The logic processing module compares the difference voltage signal with the dynamic reference voltage signal to obtain a second overcurrent protection signal; The logic processing module controls the switch module to disconnect to perform overcurrent protection on the load when determining that an overcurrent protection condition is met based on the enable signal of the overcurrent protection function and the second overcurrent protection signal.

2. The overcurrent protection method according to claim 1, characterized in that: The logic processing module determines a power control signal corresponding to the overcurrent protection circuit, and the dynamic reference voltage generator determines a corresponding dynamic reference voltage signal based on the power control signal, including: The logic processing module obtains the working power of the load corresponding to the overcurrent protection circuit; The logic processing module determines the power control signal based on the operating power and the power supply voltage connected to the overcurrent protection circuit; The dynamic reference voltage generator integrates the power control signal to obtain a dynamic reference voltage signal corresponding to the power control signal.

3. The overcurrent protection method according to claim 1, characterized in that: The logic processing module determines, according to the current signal and the dynamic reference voltage signal, that an overcurrent protection condition is reached, and controls the switch module to disconnect to perform overcurrent protection on the load, including: The logic processing module obtains a preset voltage signal; The dynamic reference voltage generator determines a target reference voltage signal based on the dynamic reference voltage signal and the preset voltage signal; The logic processing module determines a voltage signal corresponding to the current signal, compares the target reference voltage signal with the voltage signal, and obtains a first overcurrent protection signal; The logic processing module controls the switch module to disconnect to perform overcurrent protection on the load when determining that an overcurrent protection condition is met based on the enable signal of the overcurrent protection function and the first overcurrent protection signal.

4. The method according to claim 3, characterized in that The logic processing module determines, based on the overcurrent protection enable signal and the first overcurrent protection signal, that when an overcurrent protection condition is reached, controls the switch module to disconnect to perform overcurrent protection on the load, including: If the enable signal is a high level signal and the first overcurrent protection signal is a high level signal, it is determined that the overcurrent protection condition is met; Based on the high level signal, the switch module is controlled to be disconnected to cut off the overcurrent protection circuit and trigger the overcurrent protection for the load.

5. An overcurrent protection circuit, characterized in that: include: A sampling module, a logic processing module, a dynamic reference voltage generator and a switch module, wherein the sampling module is used to sample the input current of the power input terminal, the output terminal of the sampling module is connected to the logic processing module, the output terminal of the logic processing module is connected to the control terminal of the switch module, and the output terminal of the switch module is connected to the load corresponding to the overcurrent protection circuit and the power input terminal; The sampling module is used to collect the current signal connected to the overcurrent protection circuit; The logic processing module is used to determine the power control signal of the load corresponding to the overcurrent protection circuit; The dynamic reference voltage generator is used to determine a corresponding dynamic reference voltage signal based on the power control signal; The logic processing module is further used to control the switch module to disconnect to perform overcurrent protection on the load when determining that an overcurrent protection condition is reached according to the current signal and the dynamic reference voltage signal; Wherein, the logic processing module obtains a preset voltage signal; The logic processing module determines the access voltage signal corresponding to the current signal, and determines a difference voltage signal between the access voltage signal and the preset voltage signal; The logic processing module compares the difference voltage signal with the dynamic reference voltage signal to obtain a second overcurrent protection signal; The logic processing module controls the switch module to disconnect to perform overcurrent protection on the load when determining that an overcurrent protection condition is met based on the enable signal of the overcurrent protection function and the second overcurrent protection signal.

6. The overcurrent protection circuit according to claim 5, characterized in that: The logic processing module includes a main control module, and the dynamic reference voltage generator includes an analog integrator; The main control module is used to obtain the working power of the load corresponding to the overcurrent protection circuit, and determine the power control signal based on the working power and the power supply voltage connected to the overcurrent protection circuit; The analog integrator is used to perform integration processing on the power control signal to obtain a dynamic reference voltage signal corresponding to the power control signal.

7. The overcurrent protection circuit according to claim 6, characterized in that: The logic processing module further includes a comparator and a logic judgment unit, the output end of the comparator is connected to the first input end of the logic judgment unit, the second output end of the main control module is connected to the second input end of the logic judgment unit, the output end of the sampling module is connected to the first input end of the comparator, the output end of the dynamic reference voltage generator is connected to the second input end of the comparator, the output end of the logic judgment unit is connected to the control end of the switch module, and the dynamic reference voltage generator includes an analog adder; The main control module is further used to obtain a preset voltage signal and determine an access voltage signal corresponding to the current signal; The analog adder is used to perform a sum operation on the dynamic reference voltage and the preset voltage signal to determine a target reference voltage signal; The comparator is used to compare the target reference voltage signal with the access voltage signal and output a first overcurrent protection signal; The logic judgment unit is used to determine the first output signal of the logic judgment unit based on the enable signal of the overcurrent protection function and the first overcurrent protection signal; The main control module is used to control the switch module to disconnect to perform overcurrent protection on the load when determining that the overcurrent protection condition is met based on the first output signal.

8. The overcurrent protection circuit according to claim 7, characterized in that: Determine that the enable signal is a high-level signal, the first overcurrent protection signal output by the comparator is a high-level signal, and the first output signal of the logic judgment unit is a high-level signal; Determine that the first output signal of the logic judgment unit is a high level signal, and determine that the overcurrent protection condition is met.

9. The overcurrent protection circuit according to claim 7 or 8, characterized in that: The logic processing module further comprises an analog subtractor, wherein the analog subtractor is connected to the output end of the sampling module and the first input end of the comparator; The analog subtractor is used to determine a difference voltage signal between the access voltage signal and the preset voltage signal; The comparator is used to compare the difference voltage signal with the dynamic reference voltage signal and output a second overcurrent protection signal; The logic judgment unit is used to determine the second output signal of the logic judgment unit based on the enable signal of the overcurrent protection function and the second overcurrent protection signal; The main control module is used to control the switch module to disconnect to perform overcurrent protection on the load when determining that the overcurrent protection condition is met based on the second output signal.

10. A computer-readable storage medium storing executable instructions, characterized in that: When the executable instructions are executed by the processor, the overcurrent protection method according to any one of claims 1 to 4 is implemented.

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