Battery discharge circuit and protection method

Abstract

The invention discloses a battery discharge circuit and a protection method. The battery discharge circuit comprises a steady-state signal acquisition module, a transient signal acquisition module, a switch control module and a switch module, the steady-state signal acquisition module is connected with the battery and is used for acquiring an electric signal output by the battery; the transient signal acquisition module is used for acquiring an electric signal output by the battery; the switch control module is connected with the steady-state signal acquisition module and the transient signal acquisition module, and the switch control module is switched on when the voltage signal output by the steady-state signal acquisition module is greater than a first preset threshold value or is switched on when the voltage signal output by the transient signal acquisition module is greater than a second preset threshold value; the switch module is used for being switched off when the switch control module is switched on so as to inhibit electric signals output by the battery from being released through the discharging port. The battery discharging circuit provided by the invention effectively inhibits the external discharging of the discharging port caused by the increase of the output current of the battery.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic circuits, and in particular to a battery discharge circuit and a protection method. Background Art

[0002] In electronic products, the discharge energy of the battery discharge port is strictly limited. If the positive and negative electrodes of the discharge port are short-circuited, the battery will discharge externally. In a flammable gas environment, this discharge may ignite the surrounding flammable gas and cause an explosion. Therefore, in order to ensure the safety of product use and improve product reliability, it is necessary to design a protective device to suppress discharge at the battery discharge port.

[0003] At present, the protection circuit used in the battery discharge circuit generally adopts sampling resistors, switch devices, comparators or operational amplifiers, etc. The comparator or operational amplifier controls the switch device according to the electrical signal collected by the sampling resistor and the reference electrical signal. When the electrical signal collected by the sampling resistor is greater than the reference electrical signal, the comparator or operational amplifier controls the switch device to turn off. Since the comparator or operational amplifier has the characteristic of delay, when the positive and negative poles of the discharge port are short-circuited, the current of the discharge port increases rapidly, and the comparator or operational amplifier cannot control the switch device to turn off in time, and there is a safety hazard in the discharge port to discharge to the outside. Summary of the invention

[0004] The present invention provides a battery discharge circuit and protection method to solve the problem in the prior art that when the current of a discharge port increases rapidly, a switch device cannot be turned off in time, resulting in a potential safety hazard.

[0005] According to one aspect of the present invention, a battery discharge circuit is provided, comprising: a steady-state signal acquisition module, a transient signal acquisition module, a switch control module and a switch module;

[0006] The steady-state signal acquisition module is connected between the battery port and the discharge port of the battery discharge circuit, and the steady-state signal acquisition module is used to collect the electrical signal output by the battery;

[0007] The transient signal acquisition module is connected between the battery port and the discharge port, and is used to acquire the electrical signal output by the battery;

[0008] The switch control module is connected to the steady-state signal acquisition module and the transient signal acquisition module;

[0009] The switch module is connected between the battery port and the discharge port and is connected to the switch control module;

[0010] The switch control module is used to control the switch module to shut down when the voltage signal output by the steady-state signal acquisition module is greater than a first preset threshold or the voltage signal output by the transient signal acquisition module is greater than a second preset threshold, so as to disconnect the connection between the battery port and the discharge port.

[0011] Optionally, the transient signal acquisition module includes a first inductor or a first magnetic bead, a first end of the first inductor or the first magnetic bead is connected to the steady-state signal acquisition module, and a second end of the first inductor or the first magnetic bead is connected to the switch control module.

[0012] Optionally, the switch control module includes a first steady-state signal processing submodule, a first transient signal processing submodule and a switch driving submodule, the first steady-state signal processing submodule is connected to the steady-state signal acquisition module, the first steady-state signal processing submodule is used to process the signal output by the steady-state signal acquisition module, the first transient signal processing submodule is connected to the transient signal acquisition module, the first transient signal processing submodule is used to process the signal output by the transient signal acquisition module, the switch driving submodule is connected to the first steady-state signal processing submodule and the first transient signal processing submodule, and the switch driving submodule is used to drive the switch module according to the signal output by the first steady-state signal processing submodule or according to the signal output by the first transient signal processing submodule.

[0013] Optionally, the first steady-state signal processing submodule includes a first voltage stabilizing unit and a comparison unit; the first voltage stabilizing unit is connected to the battery, and is used to perform voltage stabilization processing on the voltage signal output by the battery; the comparison unit is connected to the first voltage stabilizing unit and the steady-state signal acquisition module, and the comparison unit is used to output a control signal when the voltage signal output by the steady-state signal acquisition module is greater than the first preset threshold value, and the switch driving submodule controls the switch module to turn off according to the control signal.

[0014] Optionally, the first transient signal processing submodule includes a second voltage stabilizing unit, which is connected to the transient signal acquisition module and the switch driving submodule. The second voltage stabilizing unit is used to perform voltage stabilization processing on the voltage signal output by the transient signal acquisition module, and output a control signal when the voltage signal output by the transient signal acquisition module is greater than the second preset threshold value. The switch driving submodule controls the switch module to turn off according to the control signal.

[0015] Optionally, the second voltage stabilizing unit includes a first diode, a first capacitor and a first resistor, the first end of the first diode is connected to the transient signal acquisition module, the second end of the first diode is connected to the first end of the first capacitor, the first end of the first resistor and the switch driving submodule, the second end of the first capacitor is grounded, and the second end of the first resistor is grounded.

[0016] Optionally, the battery port includes a positive port and a negative port, the discharge port includes a discharge port positive electrode and a discharge port negative electrode, the first voltage stabilizing unit includes a regulator, a first end of the regulator is connected to the positive port, and a second end of the regulator is connected to the comparison unit.

[0017] Optionally, the comparison unit includes a comparator, a second resistor, a third resistor and a second diode, the first end of the second resistor is connected to the second end of the regulator and the comparator, the second end of the second resistor is connected to the first end of the third resistor and the comparator, the second end of the third resistor is grounded, the comparator is connected to the steady-state signal acquisition module, the first end of the second diode is connected to the comparator, and the second end of the second diode is connected to the switch driving submodule.

[0018] Optionally, the switch driving submodule includes a first transistor and a fourth resistor, the control end of the first transistor is connected to the first steady-state signal processing submodule and the first transient signal processing submodule, the first end of the first transistor is connected to the first end of the fourth resistor and the switch module, the second end of the fourth resistor is connected to the discharge port, and the second end of the first transistor is grounded.

[0019] Optionally, the steady-state signal acquisition module includes a fifth resistor, a first end of the fifth resistor is connected to the battery, and a second end of the fifth resistor is connected to the transient signal acquisition module and the switch control module.

[0020] Optionally, the switch module includes a second transistor, a control end of the second transistor is connected to the switch control module, a first end of the second transistor is connected to the transient signal acquisition module, and a second end of the second transistor is connected to the discharge port.

[0021] Optionally, the transient signal acquisition module includes a second inductor or a second magnetic bead, a first end of the second inductor or the second magnetic bead is connected to the battery port, and a second end of the second inductor or the second magnetic bead is connected to the second transient signal processing submodule and the discharge port.

[0022] Optionally, the switch control module includes a second steady-state signal processing submodule and a second transient signal processing submodule, the second steady-state signal processing submodule is connected to the steady-state signal acquisition module, the second steady-state signal processing submodule is used to process the signal output by the steady-state signal acquisition module and drive the switch module to turn off when the voltage signal output by the steady-state signal acquisition module is greater than the first preset threshold value, and the second transient signal processing submodule is connected to the transient signal acquisition module, the second transient signal processing submodule is used to process the signal output by the transient signal acquisition module and drive the switch module to turn off when the voltage signal output by the transient signal acquisition module is greater than the first preset threshold value.

[0023] Optionally, the second steady-state signal processing submodule includes an operation unit, which is connected to the steady-state signal acquisition module and the switch module, and is used to drive the switch module to turn off when the voltage signal output by the steady-state signal acquisition module is greater than the first preset threshold.

[0024] Optionally, the operation unit includes an operational amplifier and a third diode; the operational amplifier is connected to the steady-state signal acquisition module, the first end of the third diode is connected to the output end of the operational amplifier, and the second end of the second diode is connected to the switch module.

[0025] Optionally, the second transient signal processing submodule includes a fourth diode, a second capacitor, a seventh resistor, a first NOT gate chip, a second NOT gate chip and a fifth diode, the first end of the fourth diode is connected to the transient signal acquisition module, the second end of the fourth diode is connected to the first end of the second capacitor, the first end of the seventh resistor and the first end of the first NOT gate chip, the second end of the second capacitor and the second end of the seventh resistor are grounded, the second end of the first NOT gate chip is connected to the first end of the second NOT gate chip, the second end of the second NOT gate chip is connected to the first end of the fifth diode, and the second end of the fifth diode is connected to the switch module.

[0026] Optionally, the steady-state signal acquisition module includes a sixth resistor, a first end of the sixth resistor is connected to the battery port, and a second end of the sixth resistor is connected to the second steady-state signal processing submodule.

[0027] Optionally, the switch module includes a third transistor, a control end of the third transistor is connected to the second steady-state signal processing submodule and the second transient signal processing submodule, a first end of the third transistor is connected to the steady-state signal acquisition module, and a second end of the third transistor is connected to the discharge port.

[0028] According to another aspect of the present invention, a battery discharging protection method is provided, the protection method being executed by the battery discharging circuit, and the protection method comprising:

[0029] The steady-state signal acquisition module and the transient signal acquisition module acquire the electrical signal output by the battery; when the voltage signal output by the steady-state signal acquisition module is greater than the first preset threshold or the voltage signal output by the transient signal acquisition module is greater than the second preset threshold, the switch control module controls the switch module to turn off, thereby disconnecting the connection between the battery port and the discharge port.

[0030] The technical solution of the embodiment of the present invention provides a battery discharge circuit, including: a steady-state signal acquisition module, a transient signal acquisition module, a switch control module and a switch module; the steady-state signal acquisition module is connected to the battery, and the steady-state signal acquisition module is used to acquire the electrical signal output by the battery; the transient signal acquisition module is connected to the steady-state signal acquisition module, and the transient signal acquisition module is used to acquire the electrical signal output by the battery; the switch control module is connected to the steady-state signal acquisition module and the transient signal acquisition module, and the switch control module is used to turn on when the voltage signal output by the steady-state signal acquisition module is greater than a first preset threshold, or turn on when the voltage signal output by the transient signal acquisition module is greater than a second preset threshold; the switch module is used to turn off when the switch control module is turned on, so as to suppress the electrical signal output by the battery from being released through the discharge port. When the signal detection module detects a sudden change in the battery output current, the transient signal acquisition module responds immediately and outputs a transient response voltage. When the voltage signal output by the transient signal acquisition module is greater than a second preset threshold, the switch control module is turned on so that the switch module is turned off in time, effectively suppressing the increase in the battery output current that causes the discharge port to discharge externally, and solving the problem in the prior art that when the current of the discharge port increases rapidly, the switch device cannot be turned off in time, causing the discharge port to discharge externally, thereby causing a safety hazard.

[0031] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0033] Figure 1 It is a circuit diagram of a battery discharge circuit provided in the related art;

[0034] Figure 2 is a circuit diagram of another battery discharge circuit provided in the related art;

[0035] Figure 3 is a structural schematic diagram of a battery discharge circuit provided by an embodiment of the present invention;

[0036] Figure 4 is a circuit diagram of a battery discharge circuit provided by an embodiment of the present invention;

[0037] Figure 5 is a circuit diagram of another battery discharge circuit provided by an embodiment of the present invention;

[0038] Figure 6 It is a curve diagram of the change of the electrical signal when the discharge port is short-circuited in the related art;

[0039] Figure 7 is a curve diagram of the change of the electrical signal when the discharge port is short-circuited according to the embodiment of the present invention;

[0040] Figure 8 is a curve diagram of discharge energy when the discharge port is short-circuited in an embodiment of the present invention;

[0041] Fig. 9 The present invention provides a flow chart of a battery discharging protection method. DETAILED DESCRIPTION

[0042] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0043] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0044] Explosion-proof safety protection is an important part of the application of electrical equipment. Electrical equipment used in explosive hazardous areas should be designed according to the explosion-proof standards of the area and pass type tests. There are many types of protection methods for electrical equipment to achieve explosion-proof functions. These methods are all achieved by limiting one of the three elements of explosion (ignition source, combustion-supporting material, and explosive material). The common explosion-proof type of handheld terminals is intrinsically safe. Intrinsically safe type achieves explosion-proof by limiting the ignition source of the three elements. For any substance, it must have enough energy to ignite it, and any explosive substance has a corresponding critical point ignition energy. If this critical ignition energy is exceeded, ignition will occur, and if it is not exceeded, it will not occur. Intrinsically safe type achieves safety by limiting energy to below the critical ignition energy.

[0045] In electronic products, the discharge energy of the battery discharge port is strictly limited. The battery connector is a connection device that connects electrical equipment and batteries and is used to transmit current. The battery connector is connected to the discharge port. When the positive and negative ends of the battery connector are short-circuited (that is, the positive and negative poles of the discharge port are short-circuited), the battery will discharge externally. If in a flammable gas environment, the battery discharges externally and may ignite the surrounding flammable gas and cause an explosion. Therefore, in order to ensure the safety of product use and improve product reliability, it is necessary to design a protective device to suppress discharge at the battery discharge port. At present, the protection circuit used in the battery discharge circuit generally uses sampling resistors, switching devices, comparators or operational amplifiers. Figure 1 is a circuit diagram of a battery discharge circuit provided in the related art, such as Figure 1 As shown, the charge and discharge management chip is connected to the positive electrode of the battery and the MOS tube, the voltage regulator chip LDO is connected to the positive electrode of the battery and the comparator, the voltage regulator chip LDO and the comparator constitute a current limiting unit, and the battery discharge circuit includes current limiting unit 1, current limiting unit 2 and current limiting unit 3. The discharge port includes a discharge port positive electrode and a discharge port negative electrode, the discharge port positive electrode is connected to the positive electrode of the battery, and the discharge port negative electrode is connected to the electronic switch (MOS tube). The sampling resistor, the comparator and the electronic switch constitute an overcurrent protection circuit, the sampling resistor is connected to the negative electrode of the battery, and the electrical signal Det collected by the sampling resistor is input into the comparator, and the comparator compares the electrical signal Det with the reference signal Vref. When the electrical signal Det is greater than the reference signal Vref, the comparator controls the electronic switch connected in series in the battery discharge circuit to turn off, thereby achieving the purpose of limiting the discharge port current. Figure 2 is a circuit diagram of another battery discharge circuit provided in the related art, such as Figure 2As shown, the charge and discharge management chip is connected to the negative electrode of the battery and the MOS tube, the discharge port includes the positive electrode of the discharge port and the negative electrode of the discharge port, and the positive electrode of the discharge port is connected to the electronic switch (MOS tube). The sampling resistor, the operational amplifier U and the electronic switch form an overcurrent protection circuit. The sampling resistor is connected to the positive electrode of the battery. The electrical signal collected by the sampling resistor is input to the operational amplifier U. The operational amplifier U processes the input electrical signal. When the electrical signal exceeds the current limiting threshold, the operational amplifier U controls the electronic switch connected in series in the battery discharge circuit to turn off, thereby achieving the purpose of limiting the current of the discharge port.

[0046] In the above-mentioned related technologies, the comparator or operational amplifier controls the switch device according to the electrical signal collected by the sampling resistor and the reference electrical signal. When the electrical signal collected by the sampling resistor is greater than the reference electrical signal, the comparator or operational amplifier controls the switch device to disconnect. However, when a short circuit occurs at the discharge port of the battery, the current at the discharge port increases rapidly. Since the comparator or operational amplifier has the characteristic of delay, the actual current limit point is much greater than the designed current limit threshold. The comparator or operational amplifier cannot control the switch device to disconnect in time, causing the discharge port to discharge to the outside. The discharge spark energy is large and is likely to ignite an explosive environment.

[0047] To solve the above problem, an embodiment of the present invention provides a battery discharging circuit. Figure 3 is a schematic diagram of a battery discharge circuit provided by an embodiment of the present invention. Figure 3 As shown, the battery discharge circuit includes a steady-state signal acquisition module 110, a transient signal acquisition module 120, a switch control module 130 and a switch module 140; the steady-state signal acquisition module 110 is connected to the battery, and the steady-state signal acquisition module 110 is used to acquire the electrical signal output by the battery; the transient signal acquisition module 120 is connected to the steady-state signal acquisition module 110, and the transient signal acquisition module 120 is used to acquire the electrical signal output by the battery; the switch control module 130 is connected to the steady-state signal acquisition module 110 and the transient signal acquisition module 120, and the switch control module 130 is used to turn on when the current signal output by the steady-state signal acquisition module 110 is greater than a first preset threshold, or to turn on when the voltage signal output by the transient signal acquisition module 120 is greater than a second preset threshold; the switch module 140 is connected to the discharge port, the battery and the switch control module 130, and the switch module 140 is used to turn off when the switch control module 130 is turned on, so as to suppress the electrical signal output by the battery from being released through the discharge port.

[0048] In this embodiment, the battery discharge circuit is a circuit for discharging the battery, and the battery supplies power to the electrical device through the battery discharge circuit. The steady-state signal acquisition module 110 is a module for collecting the electrical signal output by the battery. For example, the steady-state signal acquisition module 110 may include a sampling resistor, and the sampling resistor may convert the collected current into a voltage. The transient signal acquisition module 120 is a module that responds when the electrical signal output by the battery changes suddenly. For example, the transient signal acquisition module 120 includes a first inductor and other devices that respond quickly to the electrical signal. When the discharge port is short-circuited, the battery output current changes sharply, and the transient signal acquisition module 120 responds immediately and outputs a transient voltage. The switch control module 130 is a module that controls the switch module 140 according to the voltage signal output by the steady-state signal acquisition module 110 or the voltage signal output by the transient signal acquisition module 120. The switch module 140 is a module with a switch function. For example, the switch module 140 includes a switch device. The discharge port includes a discharge port positive pole P+ and a discharge port negative pole P-. The discharge port can be directly connected to the load or connected to a battery connector. The battery connector is connected to the load. The discharge port positive pole P+ is connected to the positive pole of the battery, and the discharge port negative pole P- is connected to the switch module 140.

[0049] In this embodiment, when the current of the battery discharge circuit increases due to a fault of the electrical equipment connected to the discharge port, the current signal output by the steady-state signal acquisition module 110 increases, and the steady-state signal acquisition module 110 transmits the collected electrical signal to the switch control module 130. If the voltage signal output by the steady-state signal acquisition module 110 is greater than the first preset threshold, the switch control module 130 is turned on according to the electrical signal collected by the steady-state signal acquisition module 110, and outputs a shutdown signal. For example, the shutdown signal can be represented by a low-level signal. The switch module 140 is turned off when the switch control module 130 outputs the shutdown signal, so that the discharge port is disconnected from the battery, thereby inhibiting the discharge port from discharging to the outside. When the current of the battery discharge circuit suddenly changes due to the short circuit of the discharge port, the current signal output by the battery suddenly changes, and the transient signal acquisition module 120 immediately responds and outputs a transient voltage. When the voltage signal output by the transient signal acquisition module 120 is greater than the second preset threshold, the switch control module 130 is turned on and outputs a shutdown signal, and the switch module 140 is turned off when the switch control module 130 outputs the shutdown signal, so that the discharge port is disconnected from the battery module, thereby suppressing the discharge port from discharging to the outside.

[0050] The technical solution of this embodiment provides a battery discharge circuit, including: a steady-state signal acquisition module, a transient signal acquisition module, a switch control module and a switch module; the steady-state signal acquisition module is connected to the battery, and the steady-state signal acquisition module is used to acquire the electrical signal output by the battery; the transient signal acquisition module is connected to the steady-state signal acquisition module, and the transient signal acquisition module is used to acquire the electrical signal output by the battery; the switch control module is connected to the steady-state signal acquisition module and the transient signal acquisition module, and the switch control module is used to turn on when the voltage signal output by the steady-state signal acquisition module is greater than a first preset threshold, or turn on when the voltage signal output by the transient signal acquisition module is greater than a second preset threshold; the switch module is used to turn off when the switch control module is turned on, so as to suppress the electrical signal output by the battery from being released through the discharge port. When the signal detection module detects a sudden change in the battery output current, the transient signal acquisition module responds immediately and outputs a transient response voltage. When the voltage signal output by the transient signal acquisition module is greater than a second preset threshold, the switch control module is turned on so that the switch module is turned off in time, effectively suppressing the increase in the battery output current that causes the discharge port to discharge externally, and solving the problem in the prior art that when the current of the discharge port increases rapidly, the switch device cannot be turned off in time, causing the discharge port to discharge externally, thereby causing a safety hazard.

[0051] Figure 4 is a circuit diagram of a battery discharge circuit provided by an embodiment of the present invention, such as Figure 4 As shown, the switch control module 130 includes a first steady-state signal processing submodule, a first transient signal processing submodule and a switch driving submodule. The first steady-state signal processing submodule is connected to the steady-state signal acquisition module. The first steady-state signal processing submodule is used to process the signal output by the steady-state signal acquisition module. The first transient signal processing submodule is connected to the transient signal acquisition module. The first transient signal processing submodule is used to process the signal output by the transient signal acquisition module. The switch driving submodule is connected to the first steady-state signal processing submodule and the first transient signal processing submodule. The switch driving submodule is used to drive the switch module according to the signal output by the first steady-state signal processing submodule or according to the signal output by the first transient signal processing submodule.

[0052] In this embodiment, the first steady-state signal processing submodule includes a first voltage stabilizing unit and a comparison unit; the first voltage stabilizing unit is connected to the battery, and the first voltage stabilizing unit is used to perform voltage stabilization processing on the voltage signal output by the battery; the comparison unit is connected to the first voltage stabilizing unit and the steady-state signal acquisition module, and the comparison unit is used to control the switch driving submodule to turn on when the voltage signal output by the steady-state signal acquisition module is greater than the first preset threshold.

[0053] In this embodiment, the first voltage stabilizing unit stabilizes the voltage output by the battery, and the voltage output by the first voltage stabilizing unit is used as the power supply voltage of the comparison unit. The comparison unit controls the on or off of the switch driving submodule by comparing the voltage output by the steady-state signal acquisition module 110 with the reference voltage, thereby achieving precise control of the switch module 140.

[0054] Specifically, the first voltage stabilizing unit includes a voltage stabilizer U1, a first end of the voltage stabilizer U1 is connected to the positive terminal of the battery, and a second end of the voltage stabilizer U1 is connected to the comparison unit. The comparison unit includes a comparator U2, a second resistor R2, a third resistor R3, and a second diode D2, a first end of the second resistor R2 is connected to the second end of the voltage stabilizer and the comparator U2, a second end of the second resistor R2 is connected to the first end of the third resistor R3 and the comparator U2, a second end of the third resistor R3 is grounded, the comparator U2 is connected to the steady-state signal acquisition module 110, a first end of the second diode D2 is connected to the comparator U2, and a second end of the second diode D2 is connected to the switch driving submodule.

[0055] In this embodiment, the first end of the voltage regulator U1 is connected to the positive electrode of the battery, and the second end of the voltage regulator U1 is connected to the first end of the second resistor R2 and the comparator U2. The voltage regulator U1 provides a working voltage for the comparator U2 after stabilizing the voltage output by the battery. The second resistor R2 and the third resistor R3 divide the output voltage of the voltage regulator U1, and use the divided voltage as the reference voltage of the comparator U2. The comparator U2 is used to compare the voltage output by the steady-state signal acquisition module 110 with the reference voltage. When the voltage output by the steady-state signal acquisition module 110 is greater than the reference voltage, the comparator U2 outputs a voltage signal, and the second diode D2 is turned on. At this time, the switch driving submodule is turned on and outputs a shutdown signal, and the switch module 140 is turned off to control the discharge port to no longer discharge to the outside.

[0056] Continue to refer Figure 4 The first transient signal processing submodule includes a second voltage stabilizing unit, which is connected to the transient signal acquisition module 120 and the switch driving submodule. The second voltage stabilizing unit is used to stabilize the voltage signal output by the transient signal acquisition module 120, and output a control signal when the voltage signal output by the transient signal acquisition module 120 is greater than a second preset threshold value. The switch driving submodule controls the switch module to turn off according to the control signal.

[0057] In this embodiment, the second voltage stabilizing unit is a unit for stabilizing the voltage output by the transient signal acquisition module 120, so that the voltage signal output by the transient signal acquisition module 120 is more stable. The switch control module 130 realizes rapid control of the switch module 140 according to the voltage signal output by the transient signal acquisition module 120.

[0058] Specifically, the transient signal acquisition module 120 includes a first inductor L1 or a first magnetic bead. Exemplarily, the transient signal acquisition module 120 uses the first inductor L1, the first end of the first inductor L1 is connected to the steady-state signal acquisition module 110, and the second end of the first inductor L1 is connected to the switch control module 130. The second voltage stabilizing unit includes a first diode D1, a first capacitor C1 and a first resistor R1, the first end of the first diode D1 is connected to the transient signal acquisition module 120, the second end of the first diode D1 is connected to the first end of the first capacitor C1, the second end of the first capacitor C1 is grounded, the first end of the first resistor R1 is connected to the first end of the first capacitor C1 and the switch driving submodule, and the second end of the first resistor R1 is grounded.

[0059] In this embodiment, the mathematical relationship between the voltage V1 across the first inductor L1 and the current i passing through the first inductor L1 is V1=L1*(di / dt). When the discharge port is short-circuited, the current collected by the steady-state signal acquisition module 110 suddenly changes, that is, the current i passing through the first inductor L1 suddenly changes. Due to the current-voltage characteristics of the first inductor, when a current sudden change occurs, the voltage will suddenly change. The voltage V1 across the first inductor L1 responds quickly according to the current i. When the current sudden change causes the voltage to suddenly change to the second preset threshold, the first diode D1 is turned on. At this time, the switch control module 130 is turned on and outputs a shutdown signal, the switch module 140 is turned off, and the discharge port no longer releases electrical energy to the outside.

[0060] Continue to refer Figure 4 , the steady-state signal acquisition module 110 includes a fifth resistor R5, a first end of the fifth resistor R5 is connected to the battery, and a second end of the fifth resistor R5 is connected to the transient signal acquisition module 120 and the switch control module 130. Among them, the fifth resistor R5 can be used as a sampling resistor to collect electrical signals in the battery discharge circuit, including voltage signals and current signals. For example, the sampling resistor calculates the current size through the voltage difference at both ends. The sampling resistor has a simple structure and simplifies the circuit structure.

[0061] Continue to refer Figure 4 The switch driving submodule includes a first transistor Q1 and a fourth resistor R4, the control end of the first transistor Q1 is connected to the comparison unit and the second voltage stabilizing unit, the first end of the first transistor Q1 is connected to the first end of the fourth resistor R4, the second end of the fourth resistor R4 is connected to the battery, and the second end of the first transistor Q1 is grounded.

[0062] The switch module 140 includes a second transistor Q2, a control end of the second transistor Q2 is connected to the switch control module 130, a first end of the second transistor Q2 is connected to the battery, and a second end of the second transistor Q2 is connected to the discharge port.

[0063] In this embodiment, the control end of the second transistor Q2 is connected to the first end of the first transistor Q1, and the second end of the second transistor Q2 is connected to the negative electrode P- of the discharge port. When the first transistor Q1 is turned on, since the second end of the first transistor Q1 is grounded, the voltage at the first end of the first transistor Q1 is close to 0V, the switch driving submodule outputs a low level signal (i.e., a shutdown signal), the second transistor Q2 is turned off, and the switch module 140 is turned off. When the first transistor Q1 is turned off, since the second end of the fourth resistor R4 is connected to the positive electrode of the battery, the voltage at the first end of the first transistor Q1 is a positive voltage, the switch driving submodule outputs a high level signal, the second transistor Q2 is turned on, and the switch module 140 is turned on.

[0064] Figure 5 is a circuit diagram of another battery discharge circuit provided by an embodiment of the present invention, such as Figure 5 As shown, the switch control module 130 includes a second steady-state signal processing submodule and a second transient signal processing submodule, the second steady-state signal processing submodule is connected to the steady-state signal acquisition module, the second steady-state signal processing submodule processes the signal output by the steady-state signal acquisition module, the second transient signal processing submodule is connected to the transient signal acquisition module, and the second transient signal processing submodule is used to process the signal output by the transient signal acquisition module. Among them, the second steady-state signal processing submodule includes an operation unit, the operation unit is connected to the steady-state signal acquisition module and the switch module, and the operation unit is used to drive the switch module to turn off when the voltage signal output by the steady-state signal acquisition module is greater than the first preset threshold.

[0065] In this embodiment, the steady-state signal acquisition module 110 includes a sixth resistor R6, the transient signal acquisition module 120 includes a second inductor L2 or a second magnetic bead, the switch module 140 includes a third transistor Q3, the operation unit includes an operational amplifier U3 and a third diode D3, and the second transient signal processing submodule includes a fourth diode D4, a second capacitor C2, a seventh resistor R7, a first NOT gate chip U4, a second NOT gate chip U5 and a fifth diode D5; the first end of the sixth resistor R6 is connected to the positive electrode of the battery port and the first input end of the operational amplifier U3, the second end of the sixth resistor R6 is connected to the second input end of the operational amplifier U3 and the first end of the third transistor Q3, the second end of the third transistor Q3 is connected to the positive electrode P+ of the discharge port, and the output end of the operational amplifier U3 is connected to The first end of the third diode D3 is connected to the control end of the third transistor Q3, the first end of the second inductor L2 or the second magnetic bead is connected to the negative electrode of the battery port (that is, the negative electrode of the battery), the second end of the second inductor L2 or the second magnetic bead is connected to the first end of the fourth diode D4 and the negative electrode P- of the discharge port, the second end of the fourth diode D4 is connected to the first end of the second capacitor C2, the first end of the seventh resistor R7 and the first end of the first NOT gate chip U4, the second end of the second capacitor C2 and the second end of the seventh resistor R7 are grounded, the second end of the first NOT gate chip U4 is connected to the first end of the second NOT gate chip U5, the second end of the second NOT gate chip U5 is connected to the first end of the fifth diode D5, and the second end of the fifth diode D5 is connected to the control end of the third transistor Q3.

[0066] In this embodiment, the switch module 140 is connected to the positive electrode P+ of the discharge port. Exemplarily, the transient signal acquisition module 120 adopts the second inductor L2. When the discharge port is not short-circuited, the voltage signal generated by the second inductor L2 is a low-level signal, the fifth diode D5 outputs a low-level signal, and the third transistor Q3 is turned on; when the discharge port is short-circuited, the current in the battery discharge circuit suddenly changes, and the voltage suddenly changes. The voltage across the second inductor L2 responds quickly according to the current. When the current mutation causes the voltage to suddenly increase to a second preset threshold, since the level signal at this time is not a high-level signal marked as stable, the first NOT gate chip U4 performs level conversion according to the level signal output by the second inductor L2. The level signal after conversion by the first NOT gate chip U4 is reversed by the second NOT gate chip U5 and then outputs a high level. The third transistor Q3 is turned off, and the discharge port no longer releases electrical energy to the outside world. The sixth resistor R6 is used as a sampling resistor, and the operational amplifier U3 receives the voltage signal collected by the sixth resistor R6 and performs signal processing. When the voltage across the sixth resistor R6 is greater than the first preset threshold, the operational amplifier U3 outputs a high-level signal, the third diode D3 is turned on, the third transistor Q3 is turned off, and the discharge port no longer releases electrical energy to the outside world.

[0067] Referring to the above embodiment, when the current signal output by the steady-state signal acquisition module 110 is greater than the first preset threshold, or the voltage signal output by the transient signal acquisition module 120 is greater than the second preset threshold, the first transistor Q1 is turned on, the switch control module 130 outputs a shutdown signal, and the switch module 140 is turned off according to the received shutdown signal. The battery discharge circuit realizes precise control of the switch module 140 and rapid control of the switch module 140.

[0068] Compared with the prior art, this embodiment adds a transient response circuit to achieve rapid control of the switch module. Figure 6 It is a curve diagram of the change of the electrical signal when the discharge port is short-circuited in the related technology, such as Figure 6 As shown, the thin solid line represents the current, the thick solid line represents the voltage, and the amplitude of the first current pulse waveform output is 46A. Figure 7 is a curve diagram of the change of the electrical signal when the discharge port is short-circuited in the embodiment of the present invention, such as Figure 7 As shown, the thick solid line is the voltage change curve, and the thin solid line is the current change curve. When the discharge port is short-circuited and the current increases rapidly, the amplitude of the first current pulse waveform output is only 1.77A, which is much lower than the current 46A without the transient response circuit. Figure 8 is a curve diagram of the discharge energy when the discharge port is short-circuited in the embodiment of the present invention, such as Figure 8 As shown, the thin solid line is the energy curve. After adding the transient current suppression circuit, the discharge energy of the discharge port is 3.12uJ, which is much lower than the 20uJ in the intrinsically safe explosion-proof circuit. The battery discharge circuit provided in this embodiment can be used in explosive environments.

[0069] The embodiment of the present invention also provides a battery discharge protection method. Fig. 9 is a flow chart of a battery discharge protection method provided by an embodiment of the present invention. Fig. 9 As shown, the battery discharge protection method includes:

[0070] S910, the steady-state signal acquisition module and the transient signal acquisition module acquire the electrical signal output by the battery.

[0071] S920: When the voltage signal output by the steady-state signal acquisition module is greater than a first preset threshold or the voltage signal output by the transient signal acquisition module is greater than a second preset threshold, the switch control module controls the switch module to turn off, disconnecting the connection between the battery port and the discharge port.

[0072] In this embodiment, the discharge port is directly connected to the load, or connected to the load through a battery connector, and the battery module supplies power to the load through the discharge port. When the load connected to the discharge port causes the current of the battery discharge circuit to increase due to a fault or other reasons, the voltage signal output by the steady-state signal acquisition module increases, and the steady-state signal acquisition module transmits the collected electrical signal to the switch control module. If the voltage signal output by the steady-state signal acquisition module is greater than the first preset threshold, the switch control module is turned on and outputs a shutdown signal according to the electrical signal collected by the steady-state signal acquisition module 110, and the switch module is turned off, which inhibits the discharge port from discharging to the outside, and realizes precise control of the switch module. When the current of the battery discharge circuit suddenly changes due to the short circuit of the discharge port, the current signal output by the battery suddenly changes, and the transient signal acquisition module immediately responds and outputs a transient voltage. When the voltage signal output by the transient signal acquisition module is greater than the second preset threshold, the switch control module is turned on and outputs a shutdown signal, and the switch module is turned off according to the shutdown signal output by the switch control module, so that the discharge port is disconnected from the battery module, inhibiting the discharge port from discharging to the outside, and realizing rapid control of the switch module.

[0073] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0074] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A battery discharge circuit, characterized in that: include: Steady-state signal acquisition module, transient signal acquisition module, switch control module and switch module; The steady-state signal acquisition module is connected between the battery port and the discharge port of the battery discharge circuit, and the steady-state signal acquisition module is used to collect the electrical signal output by the battery; The transient signal acquisition module is connected between the battery port and the discharge port, and is used to acquire the electrical signal output by the battery; The switch control module is connected to the steady-state signal acquisition module and the transient signal acquisition module; The switch module is connected between the battery port and the discharge port and is connected to the switch control module; Among them, the switch control module is used to control the switch module to shut down when the voltage signal output by the steady-state signal acquisition module is greater than a first preset threshold or the voltage signal output by the transient signal acquisition module is greater than a second preset threshold, so as to disconnect the connection between the battery port and the discharge port.

2. The battery discharge circuit according to claim 1, characterized in that: The transient signal acquisition module includes a first inductor or a first magnetic bead, a first end of the first inductor or the first magnetic bead is connected to the steady-state signal acquisition module, and a second end of the first inductor or the first magnetic bead is connected to the switch control module.

3. The battery discharge circuit according to claim 1, characterized in that: The switch control module includes a first steady-state signal processing submodule, a first transient signal processing submodule and a switch driving submodule, wherein the first steady-state signal processing submodule is connected to the steady-state signal acquisition module, the first steady-state signal processing submodule is used to process the signal output by the steady-state signal acquisition module, the first transient signal processing submodule is connected to the transient signal acquisition module, the first transient signal processing submodule is used to process the signal output by the transient signal acquisition module, the switch driving submodule is connected to the first steady-state signal processing submodule and the first transient signal processing submodule, and the switch driving submodule is used to drive the switch module according to the signal output by the first steady-state signal processing submodule or according to the signal output by the first transient signal processing submodule.

4. The battery discharge circuit according to claim 3, characterized in that: The first steady-state signal processing submodule includes a first voltage stabilizing unit and a comparison unit; the first voltage stabilizing unit is connected to the battery, and the first voltage stabilizing unit is used to perform voltage stabilization processing on the voltage signal output by the battery; the comparison unit is connected to the first voltage stabilizing unit and the steady-state signal acquisition module, and the comparison unit is used to output a control signal when the voltage signal output by the steady-state signal acquisition module is greater than the first preset threshold value, and the switch driving submodule controls the switch module to turn off according to the control signal.

5. The battery discharge circuit according to claim 4, characterized in that: The first transient signal processing submodule includes a second voltage stabilizing unit, which is connected to the transient signal acquisition module and the switch driving submodule. The second voltage stabilizing unit is used to perform voltage stabilization processing on the voltage signal output by the transient signal acquisition module, and output a control signal when the voltage signal output by the transient signal acquisition module is greater than the second preset threshold value. The switch driving submodule controls the switch module to turn off according to the control signal.

6. The battery discharge circuit according to claim 5, characterized in that: The second voltage stabilizing unit includes a first diode, a first capacitor and a first resistor, the first end of the first diode is connected to the transient signal acquisition module, the second end of the first diode is connected to the first end of the first capacitor, the first end of the first resistor and the switch driving submodule, the second end of the first capacitor is grounded, and the second end of the first resistor is grounded.

7. The battery discharge circuit according to claim 4, characterized in that: The battery port includes a positive port and a negative port, the discharge port includes a discharge port positive electrode and a discharge port negative electrode, the first voltage stabilizing unit includes a regulator, a first end of the regulator is connected to the positive port, and a second end of the regulator is connected to the comparison unit.

8. The battery discharge circuit according to claim 7, characterized in that: The comparison unit includes a comparator, a second resistor, a third resistor and a second diode, the first end of the second resistor is connected to the second end of the voltage regulator and the comparator, the second end of the second resistor is connected to the first end of the third resistor and the comparator, the second end of the third resistor is grounded, the comparator is connected to the steady-state signal acquisition module, the first end of the second diode is connected to the comparator, and the second end of the second diode is connected to the switch driving submodule.

9. The battery discharge circuit according to claim 3, characterized in that: The switch driving submodule includes a first transistor and a fourth resistor, the control end of the first transistor is connected to the first steady-state signal processing submodule and the first transient signal processing submodule, the first end of the first transistor is connected to the first end of the fourth resistor and the switch module, the second end of the fourth resistor is connected to the discharge port, and the second end of the first transistor is grounded.

10. The battery discharge circuit according to claim 2, characterized in that: The steady-state signal acquisition module includes a fifth resistor, a first end of the fifth resistor is connected to the battery, and a second end of the fifth resistor is connected to the transient signal acquisition module and the switch control module.

11. The battery discharge circuit according to claim 10, characterized in that: The switch module includes a second transistor, a control end of the second transistor is connected to the switch control module, a first end of the second transistor is connected to the transient signal acquisition module, and a second end of the second transistor is connected to the discharge port.

12. The battery discharge circuit according to claim 1, characterized in that: The transient signal acquisition module includes a second inductor or a second magnetic bead, a first end of the second inductor or the second magnetic bead is connected to the battery port, and a second end of the second inductor or the second magnetic bead is connected to the second transient signal processing submodule and the discharge port.

13. The battery discharge circuit according to claim 12, characterized in that: The switch control module includes a second steady-state signal processing submodule and a second transient signal processing submodule, the second steady-state signal processing submodule is connected to the steady-state signal acquisition module, the second steady-state signal processing submodule is used to process the signal output by the steady-state signal acquisition module and drive the switch module to turn off when the voltage signal output by the steady-state signal acquisition module is greater than the first preset threshold value, and the second transient signal processing submodule is connected to the transient signal acquisition module, the second transient signal processing submodule is used to process the signal output by the transient signal acquisition module and drive the switch module to turn off when the voltage signal output by the transient signal acquisition module is greater than the first preset threshold value.

14. The battery discharge circuit according to claim 13, characterized in that: The second steady-state signal processing submodule includes a computing unit, which is connected to the steady-state signal acquisition module and the switch module, and is used to drive the switch module to turn off when the voltage signal output by the steady-state signal acquisition module is greater than the first preset threshold.

15. The battery discharge circuit according to claim 14, characterized in that: The operation unit includes an operational amplifier and a third diode; the operational amplifier is connected to the steady-state signal acquisition module, the first end of the third diode is connected to the output end of the operational amplifier, and the second end of the second diode is connected to the switch module.

16. The battery discharge circuit according to claim 13, characterized in that: The second transient signal processing submodule includes a fourth diode, a second capacitor, a seventh resistor, a first NOT gate chip, a second NOT gate chip and a fifth diode, wherein a first end of the fourth diode is connected to the transient signal acquisition module, a second end of the fourth diode is connected to a first end of the second capacitor, a first end of the seventh resistor and a first end of the first NOT gate chip, a second end of the second capacitor and a second end of the seventh resistor are grounded, a second end of the first NOT gate chip is connected to a first end of the second NOT gate chip, a second end of the second NOT gate chip is connected to a first end of the fifth diode, and a second end of the fifth diode is connected to the switch module.

17. The battery discharge circuit according to claim 12, characterized in that: The steady-state signal acquisition module includes a sixth resistor, a first end of the sixth resistor is connected to the battery port, and a second end of the sixth resistor is connected to the second steady-state signal processing submodule.

18. The battery discharge circuit according to claim 17, characterized in that: The switch module includes a third transistor, a control end of the third transistor is connected to the second steady-state signal processing submodule and the second transient signal processing submodule, a first end of the third transistor is connected to the steady-state signal acquisition module, and a second end of the third transistor is connected to the discharge port.

19. A battery discharge protection method, characterized in that: Applied to the battery discharging circuit according to any one of claims 1 to 18, the battery discharging protection method comprises: The steady-state signal acquisition module and the transient signal acquisition module acquire the electrical signal output by the battery; when the voltage signal output by the steady-state signal acquisition module is greater than the first preset threshold or the voltage signal output by the transient signal acquisition module is greater than the second preset threshold, the switch control module controls the switch module to turn off, thereby disconnecting the connection between the battery port and the discharge port.

Images