Direct current boost circuit and energy storage power supply

Abstract

The application relates to a direct-current boosting circuit and an energy storage power supply. The direct-current boosting circuit comprises a direct-current boosting module, a current detection module and a driving control module, a first input end and an output end of the direct-current boosting module are connected with a direct-current input source and a first end of the current detection module respectively, a second end and a third end of the current detection module are connected with a battery and a first input end of the driving control module respectively, a second input end of the driving control module is used for receiving a driving signal, and an output end is connected with a second input end of the direct-current boosting module; the direct-current boosting module is used for charging the battery through an output voltage after boosting; the current detection module is used for detecting a current direction between the direct-current input source and the battery, and outputting a first level signal or a second level signal; the driving control module is used for controlling the direct-current boosting module to work when the first level signal is received, and controlling the direct-current boosting module to stop working when the second level signal is received. The circuit can prevent current from flowing back.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of battery charging, in particular to a direct current boosting circuit and an energy storage power supply. BACKGROUND

[0002] In the process of charging the battery, since the rated voltage of the battery is usually higher than the output voltage of the direct current input source, a direct current boosting circuit is usually used to raise the output voltage of the direct current input source to meet the rated charging voltage and current requirements of the battery.

[0003] In actual application, when the direct current boosting circuit is in a soft start stage, current will flow from the battery to the direct current input end through the rectifier tube in the direct current boosting circuit, which not only reduces the charging efficiency of the battery, but also brings great safety hazards.

[0004] Therefore, there is an urgent need for a direct current boosting circuit that can prevent current from flowing backward. SUMMARY

[0005] Therefore, there is an urgent need for a direct current boosting circuit that can prevent current from flowing backward.

[0006] In a first aspect, the present application provides a direct current boosting circuit, comprising: a direct current boosting module, a current detection module and a driving control module, a first input end of the direct current boosting module being connected with a direct current input source, an output end of the direct current boosting module being connected with a first end of the current detection module, a second end of the current detection module being connected with a battery, a third end of the current detection module being connected with a first input end of the driving control module, a second input end of the driving control module being used for receiving a driving signal, and an output end of the driving control module being connected with a second input end of the direct current boosting module.

[0007] The direct current boosting module is used for boosting the output voltage of the direct current input source and charging the battery through the boosted output voltage.

[0008] The current detection module is used for detecting the current direction between the direct current input source and the battery during the working process of the direct current boosting module, outputting a first level signal when the current direction is transmitted from the direct current input source to the battery, and outputting a second level signal when the current direction is transmitted from the battery to the direct current input source.

[0009] The driving control module is used for controlling the direct current boosting module to work in response to the driving signal when the first level signal is received, and controlling the direct current boosting module to stop working when the second level signal is received.

[0010] In one of the embodiments, the current detection module comprises a detection unit and a signal conversion unit, the detection unit is connected between the DC boost module and the battery, a first input end of the signal conversion unit is connected with an input end of the detection unit, a second input end of the signal conversion unit is connected with an output end of the detection unit, and a third end of the signal conversion unit is connected with a first input end of the drive control module.

[0011] The signal conversion unit is configured to detect the current flowing through the detection unit during the operation of the DC boost module, and determine the current direction between the DC input source and the battery.

[0012] When the current direction is from the DC input source to the battery, the signal conversion unit outputs a first level signal to the drive control module; and when the current direction is from the battery to the DC input source, the signal conversion unit outputs a second level signal to the drive control module.

[0013] In one of the embodiments, the detection unit comprises a resistor one, and the signal conversion unit comprises a resistor two, a resistor three, a resistor four, a first switch tube and a second switch tube.

[0014] A first end of the resistor one is connected with an output end of the DC boost module and a first end of the resistor two respectively, a second end of the resistor one is connected with an emitter of the first switch tube and a positive electrode of the battery respectively, a second end of the resistor two is connected with an emitter of the first switch tube, a base of the first switch tube is connected with a base and a collector of the second switch tube respectively, a collector of the first switch tube is connected with the first input end of the drive control module and a first end of the resistor three respectively, the collector of the second switch tube is also connected with a first end of the resistor four, and a second end of the resistor three and a second end of the resistor four are grounded.

[0015] In one of the embodiments, the drive control module comprises a first switch unit and a second switch unit, an input end of the first switch unit is connected with the third end of the current detection module, an output end of the first switch unit is connected with a first input end of the second switch unit, a second input end of the second switch unit is configured to receive a drive signal, and an output end of the second switch unit is connected with a second input end of the DC boost module.

[0016] In a case where the second level signal sent by the current detection module is received, the first switch unit and the second switch unit are both in an off state to control the DC boost module to stop working; and in a case where the first level signal sent by the current detection module is received, the first switch unit and the second switch unit are both in an on state to control the DC boost module to work in response to the drive signal.

[0017] In one of the embodiments, the first switch unit comprises a resistor five, a resistor six and a third switch tube, the first end of the resistor five is connected with the third end of the current detection module, the second end of the resistor five is connected with the base of the third switch tube, the collector of the third switch tube is connected with the first end of the resistor six, the second end of the resistor six is connected with the first input end of the second switch unit, and the emitter of the third switch tube is grounded.

[0018] In one of the embodiments, the second switch unit comprises a resistor seven, a resistor eight and a fourth switch tube, the first end of the resistor seven is used for receiving the driving signal, the second end of the resistor seven is connected with the first end of the resistor eight and the emitter of the fourth switch tube respectively, the collector of the fourth switch tube is connected with the second input end of the DC boost module, and the base of the fourth switch tube is connected with the second end of the resistor eight and the output end of the first switch unit respectively.

[0019] In one of the embodiments, the DC boost module comprises a rectifier tube and a boost unit, the DC boost circuit further comprises a driving bleed module, the first input end of the driving bleed module is connected with the output end of the boost unit, the second input end of the driving bleed module is connected with the output end of the driving control module, the output end of the driving bleed module is connected with the gate of the rectifier tube, the first input end of the boost unit is connected with the DC input source, and the second input end of the boost unit is used for receiving the driving signal.

[0020] The driving bleed module is used for turning on a path between the gate of the rectifier tube and the output end of the boost unit, and pulling down the gate voltage of the rectifier tube to control the rectifier tube to be in the closed state when the driving signal output by the driving control module is not received, and the on time of the path is less than a preset time threshold.

[0021] In one of the embodiments, the driving bleed module comprises a resistor nine and a fifth switch tube, the first end of the resistor nine is connected with the output end of the driving control module, the second end of the resistor nine is connected with the base of the fifth switch tube, the emitter of the fifth switch tube is connected with the gate of the rectifier tube, and the collector of the fifth switch tube is connected with the output end of the boost unit.

[0022] In one of the embodiments, the boost unit comprises an inductor, a resistor ten, a resistor eleven, a resistor twelve, a resistor thirteen, a capacitor, a diode and a boost tube.

[0023] The first end of the inductor is connected with the first end of the capacitor and used for receiving a boost driving signal, the second end of the inductor is connected with the first end of the resistor ten, the first end of the resistor eleven, the source of the rectifier tube and the drain of the boost tube respectively, the gate of the boost tube is connected with the first end of the resistor twelve and the first end of the resistor thirteen respectively, the second end of the resistor ten is connected with the output end of the driving control module and the positive electrode of the diode respectively, the second end of the resistor eleven is connected with the negative electrode of the diode and the gate of the rectifier tube respectively, the second end of the resistor twelve is used for inputting a driving signal, the second end of the resistor thirteen and the second end of the capacitor are grounded, and the second input end of the driving control module is used for receiving a rectification driving signal.

[0024] In a second aspect, the application further provides a storage power supply, which comprises the DC boost circuit according to any one of the first aspect.

[0025] The DC boost circuit and the storage power supply, the DC boost circuit comprises: a DC boost module, a current detection module and a driving control module, the first input end of the DC boost module is connected with a DC input source, the output end of the DC boost module is connected with the first end of the current detection module, the second end of the current detection module is connected with a battery, the third end of the current detection module is connected with the first input end of the driving control module, the second input end of the driving control module is used for receiving a driving signal, and the output end of the driving control module is connected with the second input end of the DC boost module; the DC boost module is used for boosting the output voltage of the DC input source and charging the battery through the boosted output voltage; the current detection module is used for detecting the current direction between the DC input source and the battery during the working process of the DC boost module, outputting a first level signal when the current direction is transmitted from the DC input source to the battery, and outputting a second level signal when the current direction is transmitted from the battery to the DC input source; the driving control module is used for controlling the DC boost module to work in response to the driving signal when the first level signal is received, and controlling the DC boost module to stop working when the second level signal is received. The current detection module in the DC boost circuit can detect the current direction in real time, and once the opposite current direction is found, the second level signal will be output to the driving control module, and the driving control module can timely control the DC boost module to stop working, thus preventing the continuous existence of the reverse current from the source, preventing the current from flowing backward, protecting the safety of the entire DC boost circuit, and reducing the risk of safety accidents such as fire and short circuit caused by circuit failure. In addition, by preventing the current from flowing backward, the battery is prevented from charging the DC input source in reverse, the energy consumption of the battery power is reduced, and thus the charging efficiency of the battery is improved. BRIEF DESCRIPTION OF DRAWINGS

[0026] In order to make the technical solutions in the embodiments of the present application or the related art clearer, the accompanying drawings needed to be used in the description of the embodiments of the present application or the related art will be briefly introduced. Obviously, the accompanying drawings in the following description are only some embodiments of the present application, and other related drawings can be obtained by those skilled in the art without any creative effort on the basis of these drawings.

[0027] Figure 1 First circuit schematic diagram of a DC boost circuit in an embodiment;

[0028] Figure 2 Second circuit schematic diagram of a DC boost circuit in an embodiment;

[0029] Figure 3 Third circuit schematic diagram of a DC boost circuit in an embodiment.

[0030] Explanation of reference signs:

[0031] 10: DC boost circuit; 11: DC boost module; 111: boost unit; 12: current detection module; 121: detection unit; 122: signal conversion unit; 13: drive control module; 131: first switch unit; 132: second switch unit; VCC: DC input source. DETAILED DESCRIPTION

[0032] In order to make the technical solutions in the embodiments of the present application or the related art clearer, the accompanying drawings needed to be used in the description of the embodiments of the present application or the related art will be briefly introduced. Obviously, the accompanying drawings in the following description are only some embodiments of the present application, and other related drawings can be obtained by those skilled in the art without any creative effort on the basis of these drawings.

[0033] In the process of charging the battery, since the rated voltage of the battery is often higher than the output voltage of the DC input source, it is usually necessary to use a DC boost circuit to raise the output voltage of the DC input source to meet the rated charging voltage and current requirements of the battery.

[0034] Under the driving of global energy structure transformation and carbon neutralization target, photovoltaic power generation, as one of the core technologies of clean energy, is experiencing unprecedented development opportunities. Photovoltaic power generation, with zero emissions and renewable characteristics, has become an ideal energy source for off-grid scenarios. Energy storage devices combined with photovoltaic power can meet users' demand for green power, especially in outdoor activities, emergency rescue and other scenarios without power grid coverage.

[0035] Taking photovoltaic as an example, due to the intermittence and volatility of photovoltaic power generation, it is greatly affected by light intensity; especially for portable energy storage equipment, when the photovoltaic input voltage is too low, it is difficult to charge the energy storage battery. To solve this problem, the photovoltaic voltage can be further raised by a switching direct current (BOOST) boost circuit to meet the charging demand.

[0036] In order to reduce the loss of the BOOST boost circuit, for a larger power scene, a metal-oxide semiconductor field-effect transistor (MOSFET) is usually used instead of a rectifier diode in the BOOST boost circuit. However, in this case, there is a risk of simultaneous conduction of the rectifier tube and the BOOST tube, causing irreversible damage to the BOOST boost circuit. In order to prevent this from happening, the driving of the two MOSFETs can be complementary, that is, the driving of one MOSFET is high level, and the driving of the other MOSFET is low level, and vice versa, the driving of the other MOSFET is high level.

[0037] When the BOOST boost circuit is in the soft start stage, the duty cycle is small, the inductance energy storage time is short, and the inductance current is in the discontinuous mode. Due to the complementarity of the driving of the two MOSFETs, the BOOST tube off time is too long, that is, the rectifier tube on time is too long. In this case, since the inductance current is in the discontinuous conduction mode (DCM), when the inductance current drops to zero, the rectifier tube drive is still not closed. At this time, the battery will backflow current to the photovoltaic input end, not only reducing the efficiency, but also possibly damaging the external equipment and causing greater safety hazards. It should be noted that diodes are only suitable for small power scenarios (for example, small current, small diode loss scenarios); the current in a large power scenario will be very large, and the diode will have a large loss after conduction, which requires additional heat dissipation, otherwise it will cause damage to the diode; MOS has only a small on-resistance, and the loss is relatively small.

[0038] In view of the above problems, there is an urgent need for a direct current boost circuit that can prevent current backflow. Next, the specific content of the present application will be introduced.

[0039] In one embodiment, a direct current boost circuit 10 is provided, as shown in Figure 1As shown, the direct current boosting circuit 10 comprises a direct current boosting module 11, a current detection module 12 and a driving control module 13. The first input end of the direct current boosting module 11 is connected with the direct current input source VCC. The output end of the direct current boosting module 11 is connected with the first end of the current detection module 12. The second end of the current detection module 12 is connected with the battery BAT. The third end of the current detection module 12 is connected with the first input end of the driving control module 13. The second input end of the driving control module 13 is used for receiving a driving signal. The output end of the driving control module 13 is connected with the second input end of the direct current boosting module 11.

[0040] The direct current boosting module 11 is used for boosting the output voltage of the direct current input source VCC, and charging the battery BAT through the boosted output voltage.

[0041] The current detection module 12 is used for detecting the current direction between the direct current input source VCC and the battery BAT during the working process of the direct current boosting module 11. The first level signal is output when the current direction is transmitted from the direct current input source VCC to the battery BAT. The second level signal is output when the current direction is transmitted from the battery BAT to the direct current input source VCC.

[0042] The driving control module 13 is used for controlling the direct current boosting module 11 to work in response to the driving signal when the first level signal is received. The direct current boosting module 11 is controlled to stop working when the second level signal is received.

[0043] In the embodiment of the present application, the direct current boosting module 11 in the direct current boosting circuit 10 is the BOOST boosting circuit mentioned in the related art. The direct current boosting module 11 is arranged between the direct current input source VCC and the battery BAT, and boosts the output voltage of the direct current input source VCC to charge the battery BAT. That is to say, the direct current boosting circuit 10 is an improvement on the basis of the BOOST boosting circuit. Taking photovoltaic charging as an example, the direct current input source VCC refers to photovoltaic. The output voltage of the direct current input source VCC is the output voltage of photovoltaic power generation. In the BOOST boosting circuit, elements such as inductance, rectifier tube, BOOST tube, diode and capacitor are usually included.

[0044] On the basis of the DC boost module 11, the DC boost circuit 10 further increases the current detection module 12 and the drive control module 13, the two ends of the current detection module 12 are connected between the output end of the DC boost module 11 and the battery BAT, and the output end is connected with the drive control module 13. In this way, the current detection module 12 can detect the current between the DC boost module 11 and the battery BAT in real time during the working process of the DC boost module 11, determine the current direction, and output different level signals to the drive control module 13 based on different current directions. The DC boost module 11 can include a sampling resistor and a comparison circuit, the sampling resistor can be arranged between the output end of the DC boost module 11 and the battery BAT, when the current flows through the sampling resistor, the voltage difference proportional to the current size will be generated at both ends of the sampling resistor, and then the comparison circuit compares the positive and negative of the voltage difference to determine the current direction and output the corresponding level signal.

[0045] The drive control module 13 is arranged between the third end of the current detection module 12 and the second input end of the DC boost module 11, which can control the DC boost module 11 to continue working or stop working according to the level signal output by the current detection module 12. For example, the drive control module 13 can be realized by a special control chip, which can generate appropriate pulse signals through internal circuit according to the external input drive signal, control the conduction and cut-off of the switch tube in the DC boost module 11, and realize the drive control of the DC boost module 11. Or, the drive control module 13 can also be realized by combining multiple electronic elements.

[0046] For example, when the DC input source VCC is connected to the circuit, the DC boost module 11 is in working state, and when the current detection module 12 determines that the current direction is transmitted from the DC input source VCC to the battery BAT, it means that the current direction is normal, and the DC input source VCC can normally charge the battery BAT. At this time, the current detection module 12 sends the first level signal to the drive control module 13, and after the drive control module 13 receives the first level signal, the drive signal received by the second input end of the drive control module 13 can be transmitted to the DC boost module 11, that is, the drive control module 13 can control the DC boost module 11 to continue working to ensure that the DC input source VCC continues to charge the battery BAT.

[0047] When the current detection module 12 determines that the current direction is transmitted from the battery BAT to the direct current input source VCC, it indicates that the current direction is abnormal, that is, the current in the battery BAT backflows, and the direct current input source VCC cannot charge the battery BAT. At this time, the current detection module 12 sends a second level signal to the drive control module 13, and after the drive control module 13 receives the second level signal, the drive signal received by the second input end of the drive control module 13 cannot be transmitted to the direct current boost module 11, that is, the drive control module 13 controls the direct current boost module 11 to stop working. In this way, when the current backflow occurs, the direct current boost module 11 can be turned off in time to avoid the safety hazard caused by the current backflow and improve the charging efficiency of the battery BAT.

[0048] The direct current boost circuit 10 described above comprises a direct current boost module 11, a current detection module 12, and a drive control module 13. The first input end of the direct current boost module 11 is connected with the direct current input source VCC, the output end of the direct current boost module 11 is connected with the first end of the current detection module 12, the second end of the current detection module 12 is connected with the battery BAT, the third end of the current detection module 12 is connected with the first input end of the drive control module 13, the second input end of the drive control module 13 is used for receiving a drive signal, and the output end of the drive control module 13 is connected with the second input end of the direct current boost module 11. The direct current boost module 11 is used for boosting the output voltage of the direct current input source VCC and charging the battery BAT through the boosted output voltage. The current detection module 12 is used for detecting the current direction between the direct current input source VCC and the battery BAT during the working process of the direct current boost module 11, outputting a first level signal when the current direction is transmitted from the direct current input source VCC to the battery BAT, and outputting a second level signal when the current direction is transmitted from the battery BAT to the direct current input source VCC. The drive control module 13 is used for controlling the direct current boost module 11 to work in response to the drive signal when the first level signal is received, and controlling the direct current boost module 11 to stop working when the second level signal is received. The current detection module 12 in the direct current boost circuit 10 can detect the current direction in real time. Once the opposite current direction is found, the second level signal will be output to the drive control module 13, and the drive control module 13 can control the direct current boost module 11 to stop working in time, thereby preventing the continuous existence of the reverse current and preventing the current backflow, protecting the safety of the entire direct current boost circuit 10, and reducing the risk of fire, short circuit, and other safety accidents caused by circuit failure. In addition, by preventing the current backflow, the battery BAT is prevented from charging the direct current input source VCC in reverse, thereby reducing the energy consumption of the battery BAT, and improving the charging efficiency of the battery BAT.

[0049] Next, the specific content of the current detection module 12 in the direct current boost circuit 10 described above will be described. Figure 2As shown, the current detection module 12 includes a detection unit 121 and a signal conversion unit 122, the detection unit 121 is connected between the DC boost module 11 and the battery BAT, a first input end of the signal conversion unit 122 is connected with an input end of the detection unit 121, a second input end of the signal conversion unit 122 is connected with an output end of the detection unit 121, and a third end of the signal conversion unit 122 is connected with a first input end of the drive control module 13;

[0050] The signal conversion unit 122 is configured to detect the current flowing through the detection unit 121 during the working process of the DC boost module 11, and determine the current direction between the DC input source VCC and the battery BAT.

[0051] When the current direction is from the DC input source VCC to the battery BAT, the signal conversion unit 122 outputs a first level signal to the drive control module 13; and when the current direction is from the battery BAT to the DC input source VCC, the signal conversion unit 122 outputs a second level signal to the drive control module 13.

[0052] In the embodiment, the current detection module 12 is divided into the detection unit 121 for detecting the current and the signal conversion unit 122 for analyzing the current direction and outputting the level signal according to the functions. The detection unit 121 is mainly configured to convert the current signal between the DC boost module 11 and the battery BAT into a measurable voltage signal. The detection unit 121 can be realized by a sampling resistor, or can be realized by an open-loop or closed-loop Hall current sensor. In the use process of the Hall current sensor, the magnetic field generated when the current flows through the wire is detected by the Hall element, and is converted into a voltage signal related to the current size and direction.

[0053] The signal conversion unit 122 is mainly configured to amplify, compare and convert the weak voltage signal output by the detection unit 121, and finally output a level signal recognizable by the drive control module 13. The signal conversion unit 122 can be composed of operational amplifiers, voltage comparators and other electronic elements, or can be composed of multiple switching tubes and multiple resistors.

[0054] For example, when the current direction is from the DC input source VCC to the battery BAT, the current direction is correct, and the DC input source VCC can normally charge the battery BAT. At this time, the first level signal output by the signal conversion unit 122 to the drive control module 13 can be a high level signal, and the drive control module 13 can continue to control the DC boost module 11 to work.

[0055] When the current direction is from the battery BAT to the DC input source VCC output, current reverse flow occurs, and it is necessary to immediately stop the current reverse flow. At this time, the second level signal output by the signal conversion unit 122 to the drive control module 13 can be a low level signal, and the drive control module 13 can control the DC boost module 11 to stop working.

[0056] In one embodiment, such as Figure 3 As shown, the detection unit 121 includes a resistor R1, and the signal conversion unit 122 includes a resistor R2, a resistor R3, a resistor R4, a first switch Q1, and a second switch Q2.

[0057] The first end of resistor R1 is connected to the output terminal of DC boost module 11 and the first end of resistor R2. The second end of resistor R1 is connected to the emitter of second switch Q2 and the positive terminal of battery BAT. The second end of resistor R2 is connected to the emitter of first switch Q1. The base of first switch Q1 is connected to the base and collector of second switch Q2. The collector of first switch Q1 is connected to the first input terminal of drive control module 13 and the first end of resistor R3. The collector of second switch Q2 is also connected to the first end of resistor R4. The second ends of resistor R3 and resistor R4 are grounded.

[0058] from Figure 3 As can be seen from this, with the base and collector of the second switch Q2 short-circuited, the second switch Q2 is always in a saturated conduction state. The base voltage of the second switch Q2 can be expressed as:

[0059]

[0060] Among them, V th This represents the threshold voltage at which the emitter and base of the second switch Q2 are switched on; V BAT This indicates the voltage of battery BAT.

[0061] When the DC-DC boost circuit 10 is initially powered on, the output signal of the signal conversion unit 122 is pulled low to zero by resistor R3. When the BOOST transistor in the DC-DC boost module 11 is turned off, current flows through the body diode of the rectifier Q6 in the DC-DC boost module 11 to the battery BAT. The current direction through resistor R1 is from left to right, that is, from the DC-DC boost module 11 to the battery BAT. At this time, a voltage drop will be generated across resistor R1, with the left side higher than the right side. Assuming the first switching transistor Q1 is turned on, then the emitter voltage of the first switching transistor Q1 is:

[0062]

[0063] The bias voltages between the emitter and base of the first switching transistor Q1 are:

[0064]

[0065] It can be seen that by adjusting the resistance of the second resistor R2, the voltage V R1 -V R2 >0, that is, V EB1 >V th At this time, the first switch tube Q1 meets the opening condition. Further adjust the resistance of the second resistor R2 to make it close to or in saturation conduction, the collector of the first switch tube Q1 obtains high level, then, the level signal SR_EN output by the output end of the signal conversion unit 122 is high level signal.

[0066] When the DC boost circuit 10 is in the soft start stage, the DC boost module 11 works in the DCM mode. Assuming that the inductor LD current drops to zero, the rectifier tube Q6 drive is still not closed, at this time the battery BAT discharges to the outside, that is, the current direction through the first resistor R1 is from right to left, and the voltage on the left side of the first resistor R1 is lower than that on the right side. The first resistor R1 and the second resistor R2 will produce a certain voltage drop, resulting in that the emitter voltage of the first switch tube Q1 is less than the battery BAT voltage, since the second switch tube Q2 is always in the on state, at this time, the bias voltage between the emitter and the base of the first switch tube Q1 is:

[0067]

[0068] At this time, the first switch tube Q1 is in the off state, and the collector voltage of the first switch tube Q1 is pulled low to zero by the third resistor R3, that is, the level signal SR_EN output by the output end of the signal conversion unit 122 is low level signal.

[0069] The aforementioned current detection module 12 includes a detection unit 121 and a signal conversion unit 122. The detection unit 121 is connected between the DC boost module 11 and the battery BAT. The first input terminal of the signal conversion unit 122 is connected to the input terminal of the detection unit 121, the second input terminal of the signal conversion unit 122 is connected to the output terminal of the detection unit 121, and the third terminal of the signal conversion unit 122 is connected to the input terminal of the drive control module 13. The signal conversion unit 122 is used to detect the current flowing through the detection unit 121 during the operation of the DC boost module 11, determine the current direction between the DC input source VCC and the battery BAT, and output a first-level signal to the drive control module 13 when the current direction is from the DC input source VCC to the output of the battery BAT; and output a second-level signal to the drive control module 13 when the current direction is from the battery BAT to the output of the DC input source VCC. By directly connecting the detection unit 121 between the DC boost module 11 and the battery BAT, the current flowing through the detection unit 121 can be directly captured. In this way, the signal conversion unit 122 can determine whether there is current backflow based on the detected current direction. Based on the current direction, it can accurately output the corresponding level signal to the drive control module 13, so that the drive control module 13 can identify current backflow in a timely manner based on the level signal and take corresponding protection or adjustment measures to ensure stable circuit operation.

[0070] In one embodiment, the specific contents of the drive control module 13 in the DC boost circuit 10 described above will be explained, see below. Figure 2 As shown, the drive control module 13 includes a first switch unit 131 and a second switch unit 132. The input terminal of the first switch unit 131 is connected to the third terminal of the current detection module 12, the output terminal of the first switch unit 131 is connected to the first input terminal of the second switch unit 132, the second input terminal of the second switch unit 132 is used to receive drive signals, and the output terminal of the second switch unit 132 is connected to the second input terminal of the DC boost module 11.

[0071] When the second level signal is received from the current detection module 12, both the first switch unit 131 and the second switch unit 132 are in the off state to control the DC boost module 11 to stop working; when the first level signal is received from the current detection module 12, both the first switch unit 131 and the second switch unit 132 are in the on state to control the DC boost module 11 to work in response to the drive signal.

[0072] In this embodiment, the drive control module 13 consists of two switching units, both of which have the same on / off state at the same time. When the drive control module 13 receives a second-level signal sent by the current detection module 12, it indicates that there is current backflow. The second-level signal can be a low-level signal, which drives both the first switching unit 131 and the second switching unit 132 to turn off, thus stopping the DC boost module 11 from working.

[0073] When the drive control module 13 receives the first level signal sent by the current detection module 12, it indicates that there is no backflow of current. The first level signal can be a high level signal, which drives both the first switching unit 131 and the second switching unit 132 to conduct, controlling the DC boost module 11 to continue working.

[0074] It is understood that both the first switching unit 131 and the second switching unit 132 can be composed of switching transistors and other electronic components, and the first switching unit 131 and the second switching unit 132 can be connected in series.

[0075] In one embodiment, see continue to see Figure 3 As shown, the first switching unit 131 includes resistor R5, resistor R6 and third switching transistor Q3. The first end of resistor R5 is connected to the third end of the current detection module 12, the second end of resistor R5 is connected to the base of the third switching transistor Q3, the collector of the third switching transistor Q3 is connected to the first end of resistor R6, the second end of resistor R6 is connected to the first input end of the second switching unit 132, and the emitter of the third switching transistor Q3 is grounded.

[0076] The second switching unit 132 includes a resistor R7, a resistor R8, and a fourth switching transistor Q4. The first terminal of the resistor R7 is used to receive a drive signal. The second terminal of the resistor R7 is connected to the first terminal of the resistor R8 and the emitter of the fourth switching transistor Q4. The collector of the fourth switching transistor Q4 is connected to the second input terminal of the DC boost module 11. The base of the fourth switching transistor Q4 is connected to the second terminal of the resistor R8 and the output terminal of the first switching unit 131.

[0077] In the embodiment of the present application, when powered on for the first time, the level signal SR_EN at the output end of the signal conversion unit 122 is pulled low to zero by the resistor R3, so that the third switch tube Q3 and the fourth switch tube Q4 are both in the off state. When the BOOST tube in the DC boost module 11 is off, the inductor current flows through the resistor R1 in a very short time through the body diode of the rectifier tube Q6, the level signal SR_EN at the output end of the signal conversion unit 122 is a high level signal, and the third switch tube Q3 is turned on. At this time, if the driving signal received by the second input end of the driving control module 13 is a high level, there is a current flowing through the branch composed of the resistor R6 and the resistor R8, and there is a voltage drop on the resistor R8, so that there is a positive bias voltage between the emitter and the base of the fourth switch tube Q4, and the fourth switch tube Q4 is turned on. The driving signal can normally drive the rectifier tube Q6 in the DC boost module 11, the rectifier tube Q6 is turned on, the current flows from the body of the rectifier tube Q6, and the DC input source VCC can normally charge the battery BAT. If the driving signal SR_EN received by the first input end of the driving control module 13 is a low level, there is no current flowing through the branch composed of the resistor R6 and the resistor R8, there is no voltage drop on the resistor R8, there is no bias between the emitter and the base of the fourth switch tube Q4, the fourth switch tube Q4 is off, the voltage between the gate and the source of the rectifier tube Q6 is zero, and the rectifier tube Q6 is in the off state.

[0078] When the level signal SR_EN at the output end of the signal conversion unit 122 is a low level, the third switch tube Q3 is off, and there is no positive bias voltage between the emitter and the base of the fourth switch tube Q4, so that the fourth switch tube Q4 is also in the off state.

[0079] At this time, the driving signal received by the second input end of the driving control module 13 is cut off by the fourth switch tube Q4, so that the rectifier tube Q6 in the DC boost module 11 can be controlled to be off, and the current backflow can be prevented in time.

[0080] The driving control module 13 comprises a first switch unit 131 and a second switch unit 132, an input end of the first switch unit 131 is connected with the third end of the current detection module 12, an output end of the first switch unit 131 is connected with a first input end of the second switch unit 132, a second input end of the second switch unit 132 is used for receiving a driving signal, and an output end of the second switch unit 132 is connected with the second input end of the DC voltage boosting module 11; in the case that the second level signal sent by the current detection module 12 is received, the first switch unit 131 and the second switch unit 132 are both in an off state, so as to control the DC voltage boosting module 11 to stop working; in the case that the first level signal sent by the current detection module 12 is received, the first switch unit 131 and the second switch unit 132 are both in an on state, so as to control the DC voltage boosting module 11 to work in response to the driving signal. The first switch unit 131 in the driving control module 13 is directly linked with the current detection module 12, and the second switch unit 132 is associated with the driving signal and the DC voltage boosting module 11, and the cooperation of the two-stage switches can realize accurate regulation and control of the working state of the DC voltage boosting module 11 according to the level signal output by the current detection module 12.

[0081] When the driving control module 13 controls the DC voltage boosting module 11 to stop working, because there is a junction capacitance between the gate and the source of the rectifier tube Q6 in the DC voltage boosting module 11, the voltage cannot naturally and quickly drop to zero, which prolongs the time for the DC voltage boosting module 11 to stop working, so that the current backflow cannot be immediately stopped. In view of this situation, the DC voltage boosting circuit 10 further comprises a driving discharge module 14, and next, the content of quickly controlling the rectifier tube Q6 in the DC voltage boosting module 11 to be turned off will be described in detail through an embodiment.

[0082] The DC voltage boosting module 11 comprises the rectifier tube Q6 and a voltage boosting unit 111, and the DC voltage boosting circuit 10 further comprises the driving discharge module 14, a first input end of the driving discharge module 14 is connected with an output end of the voltage boosting unit 111, a second input end of the driving discharge module 14 is connected with an output end of the driving control module 13, an output end of the driving discharge module 14 is connected with a gate of the rectifier tube Q6, a first input end of the voltage boosting unit 111 is connected with a DC input source VCC, and a second input end of the voltage boosting unit 111 is used for receiving a driving signal.

[0083] The driving discharge module 14 is used for, in the case that no driving signal output by the driving control module 13 is received, turning on a path between the gate of the rectifier tube Q6 and the output end of the voltage boosting unit 111, pulling down the gate voltage of the rectifier tube Q6, and controlling the rectifier tube Q6 to be in a closed state; the on time of the path is less than a preset time threshold.

[0084] In the embodiment of the application, the drive bleed module 14 is arranged on the DC boost module 11, and the main purpose is to rapidly lower the gate voltage of the rectifier tube Q6 in the DC boost module 11 when the drive control module 13 controls the DC boost module 11 to stop working, so that the rectifier tube Q6 in the DC boost module 11 can be rapidly turned off, the path of current backflow is cut off, and the battery BAT will not backflow current.

[0085] In one embodiment, the drive bleed module 14 includes a ninth resistor R9 and a fifth switch tube Q5, a first end of the ninth resistor R9 is connected with an output end of the drive control module 13, a second end of the ninth resistor R9 is connected with a base of the fifth switch tube Q5, an emitter of the fifth switch tube Q5 is connected with a gate of the rectifier tube Q6, and a collector of the fifth switch tube Q5 is connected with an output end of the boost unit 111.

[0086] The boost unit 111 includes an inductor LD, a tenth resistor R10, an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a capacitor CE, a diode D, and a boost tube Q7, a first end of the inductor LD is connected with a first end of the capacitor CE, and is used for receiving a boost drive signal DC_IN, a second end of the inductor LD is respectively connected with a first end of the tenth resistor R10, a first end of the eleventh resistor R11, a source of the rectifier tube Q6, and a drain of the boost tube Q7, a gate of the boost tube Q7 is respectively connected with a first end of the twelfth resistor R12 and a first end of the thirteenth resistor R13, a second end of the tenth resistor R10 is respectively connected with an output end of the drive control module and a positive electrode of the diode D, a second end of the eleventh resistor R11 is respectively connected with a negative electrode of the diode D and a gate of the rectifier tube Q6, a second end of the twelfth resistor R12 is used for inputting a drive signal DC_L1, a second end of the thirteenth resistor R13 and a second end of the capacitor CE are grounded; and a second input end of the drive control module 13 is used for receiving a rectification drive signal DC_H1.

[0087] In the embodiment of the present application, the boost tube Q7 in the boost unit 111 corresponds to the BOOST tube in the BOOST circuit. When the DC boost circuit 10 is powered on for the first time, the inductor LD first stores energy, and then the output voltage of the DC input source VCC is raised to charge the battery BAT. Therefore, when powered on, the boost drive signal DC_L1 of the boost tube Q7 is high, and the boost tube Q7 is turned on to store energy for the inductor LD. After the duration of the high level of the drive signal DC_L1 ends, the boost drive signal DC_L1 of the boost tube Q7 becomes low, and the boost tube Q7 is turned off. At this time, due to the complementarity of the drive signal DC_L1 and the rectification drive signal DC_H1, the rectification drive signal input to the second input end of the drive control module 13 is high. That is, the level of the boost drive signal DC_L1 of the boost tube Q7 is completely opposite to the level of the rectification drive signal DC_H1 input to the second input end of the drive control module 13, one is high and the other is necessarily low.

[0088] When the current exists in the reverse direction, the current detection module 12 can quickly detect that the current direction is in the reverse direction, at this time, a low-level signal is sent to the drive control module 13, and the rectification drive signal input to the second input end of the drive control module 13 is cut off by the fourth switch tube Q4. There is no capacitance between the fourth switch tube Q4 and the diode D for the output end voltage DC_S1 of the inductor LD, and the voltage between the two can be quickly pulled down to the output end voltage DC_S1 of the inductor LD by the resistor R10. Because of the existence of the junction capacitance between the gate and the source of the rectifier tube Q6, the voltage cannot naturally and quickly drop to zero. Due to the existence of the gate-source voltage of the rectifier tube Q6, the fifth switch tube Q5 is turned on, the gate voltage of the rectifier tube Q6 is quickly pulled down to the output end voltage DC_S1 of the inductor LD, so that the rectifier tube Q6 is quickly turned off, the external discharge path of the battery BAT is cut off, and the battery BAT will not flow current in the reverse direction, achieving the purpose of preventing current reverse flow.

[0089] It should be noted that the rectifier tube Q6 is a diode in the traditional BOOST circuit, and does not have a driving loss. The purpose of using the MOS tube is only to reduce the loss in the high-power application scenario. For the boost unit 111, the boost tube Q7 needs to be driven first, and the rectifier tube Q6 cannot be driven first. After the boost tube Q7 is driven, the current can flow through the body diode of the rectifier tube Q6, so that the current flows to the battery BAT end, the first switch tube Q1 is turned on, the output level of the current detection module 12 is high, and the two switch tubes in the drive control module 13 are turned on, so that the rectification drive signal can normally drive the rectifier tube Q6 to work.

[0090] The direct current boosting module 11 includes a rectifier tube Q6 and a boosting unit 111, the direct current boosting circuit 10 further includes a drive bleed module 14, a first input end of the drive bleed module 14 is connected with an output end of the boosting unit 111, a second input end of the drive bleed module 14 is connected with an output end of the drive control module 13, an output end of the drive bleed module 14 is connected with a gate of the rectifier tube Q6, a first input end of the boosting unit 111 is connected with a direct current input source VCC, and a second input end of the boosting unit 111 is used for receiving a drive signal; the drive bleed module 14 is used for, in a case where the drive signal output by the drive control module 13 is not received, turning on a passageway between the gate of the rectifier tube Q6 and the output end of the boosting unit 111, pulling down a gate voltage of the rectifier tube Q6, and controlling the rectifier tube Q6 to be in an off state; and a turn-on time of the passageway is less than a preset time threshold. When the drive signal output by the drive control module 13 is not received, the drive bleed module 14 can quickly turn on the passageway between the gate of the rectifier tube Q6 and the output end of the boosting unit 111, and forcibly turn off the rectifier tube Q6 by quickly pulling down the gate voltage. The active bleed mechanism can avoid the problems of shutdown delay or incomplete shutdown of the rectifier tube Q6 caused by residual gate charge, and ensure that the rectifier tube Q6 can quickly enter an off state when current backflow occurs, thereby greatly reducing the response time of current backflow.

[0091] In an embodiment, an energy storage power supply is also provided, and the energy storage power supply includes the content of any one of the above direct current boosting circuits 10.

[0092] The technical features of the above embodiments can be combined in any manner. To make the description concise, all possible combinations of the technical features in the above embodiments are not described, but as long as the combinations of the technical features do not exist contradictory, they should be considered as the scope of the present application.

[0093] The above embodiments only express several implementation manners of the present application, and the description is relatively specific and detailed, but it should not be understood as a limitation on the patent scope of the present application. It should be pointed out that, for ordinary skilled persons in the art, several modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A DC boost circuit, characterized in that, The DC-DC boost circuit includes: a DC-DC boost module, a current detection module, and a drive control module. The first input terminal of the DC-DC boost module is connected to a DC input source, the output terminal of the DC-DC boost module is connected to the first terminal of the current detection module, the second terminal of the current detection module is connected to a battery, the third terminal of the current detection module is connected to the first input terminal of the drive control module, the second input terminal of the drive control module is used to receive drive signals, and the output terminal of the drive control module is connected to the second input terminal of the DC-DC boost module. The current detection module includes a detection unit and a signal conversion unit. The detection unit includes a resistor one, and the signal conversion unit includes resistors two, three, and four, a first switching transistor, and a second switching transistor. The first end of resistor one is connected to the output terminal of the DC boost module and the first end of resistor two. The second end of resistor one is connected to the emitter of the second switching transistor and the positive terminal of the battery. The second end of resistor two is connected to the emitter of the first switching transistor. The base of the first switching transistor is connected to the base of the second switching transistor and the collector of the second switching transistor. The collector of the first switching transistor is connected to the first input terminal of the drive control module and the first end of resistor three. The collector of the second switching transistor is also connected to the first end of resistor four. The second ends of resistors three and four are grounded. The DC boost module is used to boost the output voltage of the DC input source and charge the battery with the boosted output voltage. The current detection module is used to detect the current direction between the DC input source and the battery during the operation of the DC boost module, and to output a first level signal from the DC input source to the battery in the current direction, and to output a second level signal from the battery to the DC input source in the current direction. The drive control module is configured to control the DC-DC boost module to operate in response to the drive signal when receiving the first level signal; and to control the DC-DC boost module to stop operating when receiving the second level signal.

2. The circuit according to claim 1, characterized in that, The drive control module includes a first switching unit and a second switching unit. The input terminal of the first switching unit is connected to the third terminal of the current detection module, the output terminal of the first switching unit is connected to the first input terminal of the second switching unit, the second input terminal of the second switching unit is used to receive drive signals, and the output terminal of the second switching unit is connected to the second input terminal of the DC boost module. Upon receiving a second-level signal from the current detection module, both the first and second switching units are in an off state to control the DC-DC boost module to stop working; upon receiving a first-level signal from the current detection module, both the first and second switching units are in an on state to control the DC-DC boost module to work in response to the drive signal.

3. The circuit according to claim 2, characterized in that, The first switching unit includes a resistor five, a resistor six, and a third switching transistor. The first end of the resistor five is connected to the third end of the current detection module, the second end of the resistor five is connected to the base of the third switching transistor, the collector of the third switching transistor is connected to the first end of the resistor six, the second end of the resistor six is ​​connected to the first input end of the second switching unit, and the emitter of the third switching transistor is grounded.

4. The circuit according to claim 2, characterized in that, The second switching unit includes a resistor seven, a resistor eight, and a fourth switching transistor. The first end of the resistor seven is used to receive the drive signal. The second end of the resistor seven is connected to the first end of the resistor eight and the emitter of the fourth switching transistor. The collector of the fourth switching transistor is connected to the second input terminal of the DC boost module. The base of the fourth switching transistor is connected to the second end of the resistor eight and the output terminal of the first switching unit.

5. The circuit according to any one of claims 1-4, characterized in that, The DC boost module includes a rectifier diode and a boost unit. The DC boost circuit also includes a drive discharge module. The first input terminal of the drive discharge module is connected to the output terminal of the boost unit. The second input terminal of the drive discharge module is connected to the output terminal of the drive control module. The output terminal of the drive discharge module is connected to the gate of the rectifier diode. The first input terminal of the boost unit is connected to the DC input source. The second input terminal of the boost unit is used to receive drive signals. The drive discharge module is used to open the path between the gate of the rectifier and the output terminal of the boost unit when no drive signal is received from the drive control module, thereby pulling down the gate voltage of the rectifier to control the rectifier to be in a closed state; the conduction time of the path is less than a preset time threshold.

6. The circuit according to claim 5, characterized in that, The drive discharge module includes a resistor nine and a fifth switching transistor. The first end of the resistor nine is connected to the output terminal of the drive control module, the second end of the resistor nine is connected to the base of the fifth switching transistor, the emitter of the fifth switching transistor is connected to the gate of the rectifier, and the collector of the fifth switching transistor is connected to the output terminal of the boost unit.

7. The circuit according to claim 5, characterized in that, The boost unit includes an inductor, resistors 10, 11, 12, and 13, a capacitor, a diode, and a boost transistor; The first end of the inductor is connected to the first end of the capacitor and is used to receive the boost drive signal. The second end of the inductor is connected to the first end of resistor 10, the first end of resistor 11, the source of the rectifier, and the drain of the boost diode. The gate of the boost diode is connected to the first end of resistor 12 and the first end of resistor 13. The second end of resistor 10 is connected to the output terminal of the drive control module and the anode of the diode. The second end of resistor 11 is connected to the cathode of the diode and the gate of the rectifier. The second end of resistor 12 is used to input the drive signal. The second end of resistor 13 and the second end of the capacitor are both grounded. The second input terminal of the drive control module is used to receive the rectified drive signal.

8. The circuit according to claim 7, characterized in that, The boost drive signal of the boost tube is opposite in level to the rectified drive signal input to the second input terminal of the drive control module.

9. The circuit according to any one of claims 1-4, characterized in that, When the DC boost circuit is in the soft-start phase, the DC boost module operates in DCM mode.

10. An energy storage power source, characterized in that, The energy storage power supply includes the DC boost circuit described in any one of claims 1-9.

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