High-efficiency buck-boost circuit

Abstract

The invention provides an efficient buck-boost circuit which comprises a power module, a sampling module, a control module, a driving module and a high-side power supply module. The control module receives the input current voltage and the output current voltage of the power module collected by the sampling module, and outputs a driving signal according to the input current voltage and the output current voltage to control the four switch modules to step down or boost so that the output voltage of the power module is close to a set voltage; the high-side power supply module is electrically connected with the control module and the driving module and supplies power to the driving module. When a motor is used for charging a battery, the high-efficiency buck-boost circuit is adopted, the utilization rate of the motor is the highest, the output voltage of the motor cannot be lowered to undervoltage, heating caused by self-loss of the motor is reduced, and the service life of the motor is prolonged.

Description

Technical Field

[0001] The present invention relates to the field of electronic power technology, and in particular to a high-efficiency step-up and step-down circuit. Background Art

[0002] In the process of using a motor to charge a battery, the problem of voltage step-up and voltage step-down needs to be dealt with. The existing technical processing methods are: 1. Control with pure analog devices; 2. Use digital control to step-up and voltage step-down.

[0003] However, existing pure analog device control cannot effectively utilize the power of the motor. When the output power of the motor is exceeded, the input voltage will be pulled to undervoltage, resulting in abnormal system operation or low stability. At the same time, the existing digital control cannot fully open the switch tube when the voltage is only increased or decreased, which has the disadvantage of low efficiency in high-power applications. Summary of the invention

[0004] In order to overcome the defects in the prior art, an object of the present invention is to provide a high-efficiency buck-boost circuit.

[0005] In order to achieve the above-mentioned object of the present invention, the present invention provides a high-efficiency buck-boost circuit, comprising:

[0006] The power module includes an H-type bridge circuit composed of four switch modules, wherein the positive pole of the motor power supply is connected to the high-side switch module at the input end of the H-type bridge circuit, and the negative pole of the motor power supply is connected to the freewheeling switch module at the input end of the H-type bridge circuit; the positive pole of the battery is connected to the high-side switch module at the output end of the H-type bridge circuit, and the negative pole of the battery is connected to the freewheeling switch module at the output end of the H-type bridge circuit;

[0007] The sampling module is electrically connected to the power module, samples the input current and voltage and the output current and voltage of the power module, compares the output current of the power module with the set value, and outputs the current comparison signal;

[0008] The control module is electrically connected to the sampling module, receives the input current voltage and the output current voltage of the power module collected by the sampling module, and adjusts the duty cycle of the output PWM signal according to the input current voltage and the output current voltage to control the four switch modules to reduce or increase the voltage, fully turn on or completely turn off so that the output voltage of the power module is close to the set voltage;

[0009] The driving module is electrically connected to the control module, the power module, and the sampling module, receives the PWM signal output by the control module and the output current comparison signal of the sampling module, and drives the four switch modules of the power module to step down or step up, fully turn on or fully turn off;

[0010] The high-side power supply module is electrically connected to the control module and the drive module to provide power to the drive module.

[0011] Optionally, when only the high-side switch module and the freewheeling switch module at the input end of the H-type bridge circuit step down, the control module outputs a high-level signal to control the driving module to output a high-level signal to drive the high-side switch module at the output end of the H-type bridge circuit to be fully turned on;

[0012] When only the high side switch module and the freewheeling switch module at the output end of the H-type bridge circuit are boosted, the control module outputs a high level signal to control the driving module to output a high level signal to drive the high side switch module at the input end of the H-type bridge circuit to be fully turned on.

[0013] Optionally, the power module further includes an LC filter circuit;

[0014] The positive pole of the motor power supply is connected to an LC filter circuit and then to the high-side switch module at the input end of the H-type bridge circuit; a first inductor L1 is electrically connected between the output end of the high-side switch module at the input end of the H-type bridge circuit and the input end of the high-side switch module at the output end of the H-type bridge circuit.

[0015] Optionally, the sampling module includes an input current and voltage sampling circuit, an output current and voltage sampling circuit, and an output current comparison circuit;

[0016] The input current and voltage sampling circuit comprises an input current sampling circuit and an input voltage sampling circuit;

[0017] The input current sampling circuit includes an input current sampling chip IC2 and an input current sampling resistor R42, wherein the input current sampling resistor R42 is electrically connected to the voltage output end of the motor; the input current sampling chip IC2 collects the current signal flowing through the input current sampling resistor R42 and outputs it to the corresponding signal input end of the control module;

[0018] The input voltage sampling circuit includes an input voltage sampling chip U6, the positive phase end of the input voltage sampling chip U6 is connected to the positive pole of the motor power supply, the negative phase end of the input voltage sampling chip U6 is connected to the negative pole of the motor power supply, and the output end of the input voltage sampling chip U6 is connected to the corresponding signal input end of the control module;

[0019] The output current and voltage sampling circuit comprises an output current sampling circuit and an output voltage sampling circuit;

[0020] The output current sampling circuit includes an output current sampling chip IC1 and an output current sampling resistor R2, wherein the output current sampling resistor R2 is electrically connected to the voltage input terminal of the battery; the output current sampling chip IC1 collects the current signal flowing through the output current sampling resistor R2 and outputs it to the corresponding signal input terminal of the control module;

[0021] The output voltage sampling circuit includes an output voltage sampling chip U7, the positive phase end of the output voltage sampling chip U7 is connected to the positive electrode of the battery, the negative phase end of the output voltage sampling chip U7 is connected to the negative electrode of the battery, and the output end of the output voltage sampling chip U7 is connected to the corresponding signal input end of the control module;

[0022] The output current comparison circuit includes a comparison chip IC10A, a positive phase terminal of the comparison chip IC10A is connected to the current signal output terminal of the output current sampling circuit, an inverting terminal of the comparison chip IC10A inputs a set current value, and an output terminal of the comparison chip IC10A is connected to a corresponding signal input terminal of the driving module.

[0023] Optionally, the driving module includes a first switch driver U2, a second switch driver U4 and a logic circuit U5, the logic AND gate circuit U5 is connected to the control module, and the first switch driver U2 and the second switch driver U4 are respectively connected to the logic AND gate circuit U5;

[0024] A buck-boost control signal output terminal of the first switch driver U2 is connected to the buck-boost control terminal of the high-side switch module at the input end of the H-type bridge circuit, and another buck-boost control signal output terminal of the first switch driver U2 is connected to the buck-boost control terminal of the freewheeling switch module at the input end of the H-type bridge circuit; the high-side power supply terminal of the first switch driver U2 is connected to the voltage output terminal of the high-side power supply module; the power supply terminal of the first switch driver U2 is connected to the output terminal of the high-side switch module at the input end of the H-type bridge circuit;

[0025] A buck-boost control signal output terminal of the second switch driver U4 is connected to the buck-boost control terminal of the high-side switch module at the output end of the H-type bridge circuit, and another buck-boost control signal output terminal of the second switch driver U4 is connected to the buck-boost control terminal of the freewheeling switch module at the output end of the H-type bridge circuit; the high-side power supply terminal of the second switch driver U4 is connected to the voltage output terminal of the high-side power supply module; the power supply terminal of the second switch driver U4 is connected to the input terminal of the high-side switch module at the output end of the H-type bridge circuit.

[0026] Optionally, the high-side power supply module includes a current and voltage amplification module and a transformer T1, and the transformer T1 includes two sets of secondary coils;

[0027] The PWM signal output end of the control module is connected to the electrical signal input end of the current and voltage amplification module, and its voltage output end is connected to the transformer T1. The voltage output end of the first group of secondary coils of the transformer T1 is connected to the high-side power supply end of the driving module, and the voltage output end of the second group of secondary coils of the transformer T1 is connected to the high-side power supply end of the driving module.

[0028] Optionally, a power supply module is also included, which provides power for the power consumption module of the high-efficiency buck-boost circuit.

[0029] Optionally, a communication module is further included, and the communication module is communicatively connected with the control module.

[0030] The beneficial effects of the present invention are: when the motor is used to charge the battery, the high-efficiency buck-boost circuit is used, which has the following advantages:

[0031] 1. The motor utilization rate is maximized and the motor output voltage will not be pulled down to undervoltage;

[0032] 2. Reduce the heat caused by the motor's self-loss and increase the motor's service life;

[0033] 3. High conversion efficiency, which minimizes the heating of the switch tube, especially in high-power applications;

[0034] 4. Good function under efficient conversion and small size.

[0035] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0037] Figure 1 It is a principle block diagram of the first embodiment;

[0038] Figure 2 It is the circuit diagram of the power module;

[0039] Figure 3 is the schematic diagram of the input current sampling circuit;

[0040] Figure 4 is a schematic diagram of the input voltage sampling circuit;

[0041] Figure 5 is a schematic diagram of the output current sampling circuit;

[0042] Figure 6 is a schematic diagram of the output voltage sampling circuit;

[0043] Figure 7 is a schematic diagram of the output current comparison circuit;

[0044] Figure 8 It is a schematic diagram of the connection of logic and gate circuits;

[0045] Fig. 9 is a schematic diagram of the connection of a first switch driver circuit;

[0046] Fig.10 is a schematic diagram of the connection of the second switch driver circuit;

[0047] Fig.11 This is the schematic diagram of the high-side power supply module circuit

[0048] Fig.12 It is the circuit diagram of the control module;

[0049] Fig.13 It is the schematic diagram of the power module circuit;

[0050] Fig.14 It is the circuit diagram of the communication module. DETAILED DESCRIPTION

[0051] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0052] In the description of the present invention, unless otherwise specified and limited, it should be noted that the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a mechanical connection or an electrical connection, or it can be the internal connection between two components. It can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to the specific circumstances.

[0053] Embodiment 1

[0054] This embodiment provides a high-efficiency buck-boost circuit. Figures 1 to 14 As shown, specifically including:

[0055] The power module includes an H-type bridge circuit composed of four switch modules, wherein the positive pole of the motor power supply is connected to the high-side switch module at the input end of the H-type bridge circuit, and the negative pole of the motor power supply is connected to the freewheeling switch module at the input end of the H-type bridge circuit; the positive pole of the battery is connected to the high-side switch module at the output end of the H-type bridge circuit, and the negative pole of the battery is connected to the freewheeling switch module at the output end of the H-type bridge circuit;

[0056] The sampling module is electrically connected to the power module, samples the input current and voltage and the output current and voltage of the power module, compares the output current of the power module with the set value, and outputs a current comparison signal.

[0057] The control module is electrically connected to the sampling module, receives the input current voltage and output current voltage of the power module collected by the sampling module, and adjusts the duty cycle of the output PWM signal according to the input current voltage and output current voltage to control the four switch modules to reduce or increase the voltage, fully turn on or completely turn off, so that the output voltage of the power module is close to the set voltage.

[0058] The driving module is electrically connected to the control module, the power module, and the sampling module, receives the PWM signal output by the control module and the output current comparison signal of the sampling module, and drives the four switch modules of the power module to reduce or increase the voltage, fully turn on or completely turn off.

[0059] The high-side power supply module is electrically connected to the control module and the drive module to provide power to the drive module.

[0060] In single step-down, that is, only the high-side switch module and the freewheeling switch module at the input end of the H-type bridge circuit step down the voltage, the control module outputs a high-level signal to control the drive module to output a high-level signal to drive the high-side switch module at the output end of the H-type bridge circuit to be fully turned on.

[0061] In single boost, when only the high-side switch module and the freewheeling switch module at the output end of the H-type bridge circuit are boosted, the control module outputs a high-level signal to control the drive module to output a high-level signal to drive the high-side switch module at the input end of the H-type bridge circuit to be fully turned on.

[0062] The power module provides power for the power module of the high-efficiency buck-boost circuit, and mainly includes a control module and a drive module. The circuit diagram of this embodiment is as follows Fig.13 shown.

[0063] The communication module is connected to the control module for communication, and can upload monitoring data and execute communication commands to adjust voltage and current. Fig.14 shown.

[0064] like Figure 2 As shown, the power module also includes an LC filtering circuit, the positive pole of the motor power supply is connected to the LC filtering circuit and then connected to the high-side switch module at the input end of the H-type bridge circuit, and the negative pole of the motor power supply is connected to the freewheeling switch module at the input end of the H-type bridge circuit; the positive pole of the battery is connected to the high-side switch module at the output end of the H-type bridge circuit, and the negative pole of the battery is connected to the freewheeling switch module at the output end of the H-type bridge circuit, and a first inductor L1 for energy storage is electrically connected between the output end of the high-side switch module at the input end of the H-type bridge circuit and the input end of the high-side switch module at the output end of the H-type bridge circuit.

[0065] In this embodiment, Figure 2As shown, the LC filter circuit includes a first filter capacitor CE10, a third inductor L3 and a second filter capacitor CE4, the high-side switch module at the input end of the H-type bridge circuit includes a first MOS tube Q7, the freewheeling switch module at the input end of the H-type bridge circuit includes a second MOS tube Q6, the high-side switch module at the output end of the H-type bridge circuit includes a third MOS tube Q3, and the freewheeling switch module at the output end of the H-type bridge circuit includes a fourth MOS tube Q10.

[0066] Among them, Figure 2 Shown and Figure 8 As shown, the D pole of the first MOS tube Q7 is connected to the output end of the third inductor L3, and the S pole of the first MOS tube Q7 is connected to the input end of the first inductor L1; the G pole of the first MOS tube Q7 is connected to the seventh resistor R7 and the first resistor R1 and the first diode D1 connected in series, and the cathode of the first diode D1 and the seventh resistor R7 are connected together as the buck-boost control end of the high-side switch module of the H-type bridge circuit input end, and are connected to the buck-boost control signal output end of the driving module, which is the HO end of the first switch driver U2 of the driving module in this embodiment; the thirty-eighth resistor R38 and the first voltage regulator diode DZ3 connected in parallel are also connected between the S pole and the G pole of the first MOS tube Q7, and the first capacitor C1 and the ninetieth resistor R90 connected in series are also connected between the D pole and the S pole of the first MOS tube Q7.

[0067] The D pole of the second MOS tube Q6 is connected to the S pole of the first MOS tube Q7, the S pole of the second MOS tube Q6 is grounded, and is also connected to the negative pole of the power supply of the motor; the G pole of the second MOS tube Q6 is connected to the twenty-fourth resistor R24 ​​and the eighteenth resistor R18 and the second diode D7 in series, the negative pole of the second diode D7 and the twenty-fourth resistor R24 ​​are connected together as the buck-boost control end of the freewheeling switch module at the input end of the H-bridge circuit, and are connected to another buck-boost control signal output end of the driving module, which is the LO end of the first switch driver U2 of the driving module in this embodiment; the thirtieth resistor R30 and the second voltage stabilizing diode DZ6 in parallel are also connected between the S pole and the G pole of the second MOS tube Q6, and the second capacitor C8 and the one-hundred-and-seventeenth resistor R117 are also connected in series between the D pole and the S pole of the second MOS tube Q6.

[0068] like Figure 2 Shown and Fig. 9As shown, the D pole of the third MOS tube Q3 is connected to the positive pole of the battery, and the S pole of the third MOS tube Q3 is connected to the output end of the first inductor L1; the G pole of the third MOS tube Q3 is connected to the tenth resistor R10 and the fourth resistor R4 and the third diode D4 connected in series, and the cathode of the third diode D4 and the tenth resistor R10 are connected together as the buck-boost control end of the high-side switch module at the output end of the H-type bridge circuit, and are connected to another buck-boost control signal output end of the driving module, which is the HO end of the second switch driver U4 in this embodiment; the fifteenth resistor R15 and the third voltage stabilizing diode DZ9 connected in parallel are also connected between the S pole and the G pole of the third MOS tube Q3, and the third capacitor C4 and the one-hundred-and-twentieth resistor R120 connected in series are also connected between the D pole and the S pole of the third MOS tube Q3.

[0069] The D pole of the fourth MOS tube Q10 is connected to the S pole of the third MOS tube Q7, the S pole of the fourth MOS tube Q10 is grounded, and is also connected to the negative pole of the battery; the G pole of the fourth MOS tube Q10 is connected to the twenty-seventh resistor R27 and the twenty-first resistor R21 and the fourth diode D10 connected in series, the negative pole of the fourth diode D10 and the twenty-seventh resistor R27 are connected together as the buck-boost control end of the freewheeling switch module at the output end of the H-type bridge circuit, and are connected to another buck-boost control signal output end of the drive module, which is the LO end of the second switch driver U4 in this embodiment; the thirty-third resistor R33 and the fourth voltage stabilizing diode DZ12 in parallel are also connected between the S pole and the G pole of the fourth MOS tube Q10, and the fourth capacitor C12 and the one-hundred-and-twenty-third resistor R123 are also connected in series between the D pole and the S pole of the fourth MOS tube Q10.

[0070] A fifth capacitor C7 for filtering is connected between the D pole of the third MOS transistor Q3 and the S pole of the fourth MOS transistor Q10.

[0071] In this embodiment, the sampling module includes an input current and voltage sampling circuit, an output current and voltage sampling circuit, and an output current comparison circuit.

[0072] Wherein, the input current and voltage sampling circuit includes an input current sampling circuit and an input voltage sampling circuit; Figure 3 As shown, the input current sampling circuit includes an input current sampling chip IC2 and an input current sampling resistor R42. The input current sampling resistor R42 is electrically connected to the voltage output terminal of the motor, and in this embodiment is connected between the negative power supply VI N- of the motor and the ground; the input current sampling chip IC2 collects the current signal flowing through the input current sampling resistor R42 and outputs it to the corresponding signal input terminal of the control module. Figure 4As shown, the input voltage sampling circuit includes an input voltage sampling chip U6, the positive phase end of the input voltage sampling chip U6 is connected to the positive power supply electrode I N+ of the motor, the negative phase end of the input voltage sampling chip U6 is connected to the negative power supply electrode VI N- of the motor, and the output end of the input voltage sampling chip U6 is connected to the corresponding signal input end of the control module.

[0073] The output current and voltage sampling circuit includes an output current sampling circuit and an output voltage sampling circuit. Figure 5 As shown, the output current sampling circuit includes an output current sampling chip IC1 and an output current sampling resistor R2, the output current sampling resistor R2 is electrically connected to the voltage input terminal of the battery, and in this embodiment is connected between the negative electrode of the battery and the ground; the output current sampling chip IC1 collects the current signal flowing through the output current sampling resistor R2 and outputs it to the corresponding signal input terminal of the control module. Figure 6 As shown, the output voltage sampling circuit includes an output voltage sampling chip U7, the positive phase end of the output voltage sampling chip U7 is connected to the positive electrode of the battery, which is the VOUT+ end of the power module in this embodiment, the negative phase end of the output voltage sampling chip U7 is connected to the negative electrode of the battery, which is the VOUT- end of the power module in this embodiment, and the output end AD_OUT_1 of the output voltage sampling chip U7 is connected to the corresponding signal input end of the control module.

[0074] like Figure 7 As shown, the output current comparison circuit includes a comparison chip IC10A, a positive phase terminal of the comparison chip IC10A is connected to the current signal output terminal AD_OUT_1 of the output current sampling circuit, an inverting terminal of the comparison chip IC10A inputs a set current value, and an output terminal PWM-1-OP of the comparison chip IC10A is connected to a logic AND gate circuit U5 of the driving module.

[0075] In this embodiment, the driving module includes a first switch driver U2, a second switch driver U4 and a logic AND gate circuit U5. The logic AND gate circuit U5 is connected to the control module, and the first switch driver U2 and the second switch driver U4 are respectively connected to the logic AND gate circuit U5.

[0076] The logic AND gate circuit U5 includes four groups of AND gate circuits. Figure 8 , 9 As shown in 10, the two input terminals 1A and 1B of the first group of AND gate circuits are respectively connected to the 31-pin output terminal of the control module and the output terminal PWM-1-OP of the output current comparison circuit of the sampling circuit, and the output terminal 1Y of the first group of AND gate circuits is connected to the H1 terminal of the second switch driver U4.

[0077] The two input terminals 2A and 2B of the second AND gate circuit are respectively connected to the 26-pin output terminal of the control module and the output terminal PWM-1-OP of the output current comparison circuit of the sampling circuit, and the output terminal 2Y of the second AND gate circuit is connected to the L1 terminal of the first switch driver U2.

[0078] The two input terminals 3A and 3B of the third AND gate circuit are respectively connected to the 25-pin output terminal and the 29-pin output terminal of the control module, and the output terminal 3Y of the third AND gate circuit is connected to the H1 terminal of the first switch driver U2.

[0079] The two input terminals 4A and 4B of the fourth AND gate circuit are respectively connected to the 33-pin output terminal and the 32-pin output terminal of the control module, and the output terminal 4Y of the fourth AND gate circuit is connected to the L1 terminal of the second switch driver U4.

[0080] like Fig. 9 As shown, a buck-boost control signal output terminal HO of the first switch driver U2 is connected to the buck-boost control terminal of the high-side switch module at the input end of the H-type bridge circuit, another buck-boost control signal output terminal LO of the first switch driver U2 is connected to the buck-boost control terminal of the freewheeling switch module at the input end of the H-type bridge circuit, the BST high-side power supply terminal of the first switch driver U2 is connected to the voltage output by the high-side power supply module, and the SW terminal of the first switch driver U2 is connected to the output terminal DG_LS of the high-side switch module at the input end of the H-type bridge circuit.

[0081] like Fig.10 As shown, the buck-boost control signal output terminal HO of the second switch driver U4 is connected to the buck-boost control terminal of the high-side switch module at the output end of the H-type bridge circuit, the other buck-boost control signal output terminal LO of the second switch driver U4 is connected to the buck-boost control terminal of the freewheeling switch module at the output end of the H-type bridge circuit, the BST high-side power supply terminal of the second switch driver U4 is connected to the voltage output by the high-side power supply module, and the SW terminal of the second switch driver U4 is connected to the input terminal DG_RS of the high-side switch module at the output end of the H-type bridge circuit.

[0082] Based on the above circuit, when the output current of the power module is lower than the set value, the output current comparison circuit outputs a low level to the first group of AND gate circuits and the second AND gate circuit of the logic AND gate circuit U5, and the output terminal 1Y of the first group of AND gate circuits of the logic AND gate circuit U5 outputs a low level signal to the H1 terminal of the second switch driver U4, and the high side HO terminal of the second switch driver U4 outputs a low level, so that the third MOS tube Q3 is turned off; the output terminal 2Y of the second group of AND gate circuits of the logic AND gate circuit U5 outputs a low level signal to the L1 terminal of the first switch driver U2, and the low side LO terminal of the first switch driver U2 outputs a low level, so that the second MOS tube Q6 is turned off. In this way, asynchronous buck or synchronous boost is achieved without the risk of current backflow.

[0083] In this embodiment, Fig.11 As shown, the high-side power supply module includes a current and voltage amplifier module IC4 and a transformer T1, and the transformer T1 includes two groups of secondary coils; the PWM signal output end of the control module is connected to the electrical signal input end of the current and voltage amplifier module, and its voltage output end is connected to the transformer T1, and the voltage output end of the first group of secondary coils of the transformer T1 is connected to the BST high-side power supply end of the first switch driver U2 of the driving module to power the first switch driver U2, and the voltage output end of the second group of secondary coils of the transformer T1 is connected to the BST high-side power supply end of the second switch driver U4 of the driving module to power the second switch driver U4.

[0084] Control principle: The control module determines whether the input voltage of the power module is higher than the output voltage based on the input current voltage and output current voltage collected by the sampling module.

[0085] When the input voltage of the power module is higher than the output voltage, the control module starts the buck mode, the control module reduces the duty cycle of the PWM signal of the second group of AND gate circuits output to the logic AND gate circuit U5, the output end 2Y of the second group of AND gate circuits outputs a corresponding signal to the L1 end of the first switch driver U2, the low side LO end of the first switch driver U2 outputs a corresponding signal to control the second MOS tube Q6 to step down, the control module reduces the duty cycle of the PWM signal of the third group of AND gate circuits output to the logic AND gate circuit U5, the output end 3Y of the third group of AND gate circuits outputs a corresponding signal to the H1 end of the first switch driver U2, and the high side HO end of the first switch driver U2 outputs a corresponding signal to control the first MOS tube Q7 to step down. The control module adjusts the duty cycle of the PWM signal of the first group of AND gate circuits output to the logic AND gate circuit U5 to 100%, the output terminal 1Y of the first group of AND gate circuits continuously outputs a high level signal to the H1 terminal of the second switch driver U4, and the high side HO terminal of the second switch driver U4 continuously outputs a high level to fully turn on the third MOS tube Q3. The control module adjusts the duty cycle of the PWM signal of the fourth group of AND gate circuits output to the logic AND gate circuit U5 to 0%, the output terminal 4Y of the fourth group of AND gate circuits continuously outputs a low level signal to the L1 terminal of the second switch driver U4, and the low side LO terminal of the second switch driver U4 continuously outputs a low level to fully turn off the fourth MOS tube 10. The addition of the high side power supply module enables the third MOS tube Q3 to be fully turned on and the fourth MOS tube Q10 to be fully turned off, so the efficiency can be improved.

[0086] When the input voltage of the power module is lower than the output voltage, the control module starts the boost mode, the control module increases the duty cycle of the PWM signal of the first group of AND gate circuits output to the logic AND gate circuit U5, the output terminal 1Y of the first group of AND gate circuits outputs a corresponding signal to the H1 terminal of the second switch driver U4, the high side HO terminal of the second switch driver U4 outputs a corresponding signal to boost the third MOS tube Q3, the control module increases the duty cycle of the PWM signal of the fourth group of AND gate circuits output to the logic AND gate circuit U5, the output terminal 4Y of the fourth group of AND gate circuits outputs a corresponding signal to the L1 terminal of the second switch driver U4, the low side LO terminal of the second switch driver U4 outputs a corresponding signal to boost the fourth MOS tube Q10. The control module adjusts the duty cycle of the PWM signal of the third group of AND gate circuits output to the logic AND gate circuit U5 to 100%, the output terminal 3Y of the third group of AND gate circuits continuously outputs a high-level signal to the H1 terminal of the first switch driver U2, and the high-side HO terminal of the first switch driver U2 continuously outputs a high-level signal to fully turn on the first MOS tube Q7. The control module adjusts the duty cycle of the PWM signal of the second group of AND gate circuits output to the logic AND gate circuit U5 to 0%, the output terminal 2Y of the second group of AND gate circuits continuously outputs a low-level signal to the L1 terminal of the first switch driver U2, and the low-side LO terminal of the first switch driver U2 continuously outputs a low-level signal to fully turn off the second MOS tube Q6. The addition of the high-side power supply module enables the first MOS tube Q7 to be fully turned on and the second MOS tube Q6 to be fully turned off, so the efficiency can be improved.

[0087] When the input voltage is close to the output voltage, the control module reduces the duty cycle of the PWM signal of the second group of AND gate circuits output to the logic AND gate circuit U5, the output end 2Y of the second group of AND gate circuits outputs a corresponding signal to the L1 end of the first switch driver U2, the low side LO end of the first switch driver U2 outputs a corresponding signal to reduce the voltage of the second MOS tube Q6, the control module reduces the duty cycle of the PWM signal of the third group of AND gate circuits output to the logic AND gate circuit U5, the output end 3Y of the third group of AND gate circuits outputs a corresponding signal to the H1 end of the first switch driver U2, the high side HO end of the first switch driver U2 outputs a corresponding signal to reduce the voltage of the first MOS tube Q7. The control module increases the duty cycle of the PWM signal of the first group of AND gate circuits output to the logic AND gate circuit U5, the output terminal 1Y of the first group of AND gate circuits outputs a corresponding signal to the H1 terminal of the second switch driver U4, the high side HO terminal of the second switch driver U4 outputs a corresponding signal to boost the third MOS tube Q3, the control module increases the duty cycle of the PWM signal of the fourth group of AND gate circuits output to the logic AND gate circuit U5, the output terminal 4Y of the fourth group of AND gate circuits outputs a corresponding signal to the L1 terminal of the second switch driver U4, the low side LO terminal of the second switch driver U4 outputs a corresponding signal to boost the fourth MOS tube Q10, to ensure that the output voltage is close to the set voltage.

[0088] If a serious overcurrent, short circuit, or overvoltage condition occurs, the control module outputs a PWM signal with a duty cycle of 0 to the 3A terminal of the third group of AND gate circuits and the 4A terminal of the fourth group of AND gate circuits of the logic AND gate circuit U5, the third group of AND gate circuits of the logic AND gate circuit U5 outputs a low level to the H1 terminal of the first switch driver U2, the first switch driver U2 outputs a low level to the buck-boost control terminal of the first MOS tube Q7, turns off the first MOS tube Q7, blocks the input, the fourth group of AND gate circuits of the logic AND gate circuit U5 outputs a low level signal to the L1 terminal of the second switch driver U4, the second switch driver U4 outputs a low level to the buck-boost control terminal of the fourth MOS tube Q10, the fourth MOS tube Q10 is turned off, and the output is blocked.

[0089] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0090] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A high-efficiency buck-boost circuit, characterized in that: include: The power module includes an H-type bridge circuit composed of four switch modules, wherein the positive pole of the motor power supply is connected to the high-side switch module at the input end of the H-type bridge circuit, and the negative pole of the motor power supply is connected to the freewheeling switch module at the input end of the H-type bridge circuit; the positive pole of the battery is connected to the high-side switch module at the output end of the H-type bridge circuit, and the negative pole of the battery is connected to the freewheeling switch module at the output end of the H-type bridge circuit; The sampling module is electrically connected to the power module, samples the input current and voltage and the output current and voltage of the power module, compares the output current of the power module with the set value, and outputs the current comparison signal; The control module is electrically connected to the sampling module, receives the input current voltage and the output current voltage of the power module collected by the sampling module, and adjusts the duty cycle of the output PWM signal according to the input current voltage and the output current voltage to control the four switch modules to reduce or increase the voltage, fully turn on or completely turn off so that the output voltage of the power module is close to the set voltage; The driving module is electrically connected to the control module, the power module, and the sampling module, receives the PWM signal output by the control module and the output current comparison signal of the sampling module, and drives the four switch modules of the power module to step down or step up, fully turn on or fully turn off; The high-side power supply module is electrically connected to the control module and the drive module to provide power to the drive module.

2. The high-efficiency buck-boost circuit according to claim 1, characterized in that: When only the high-side switch module and the freewheeling switch module at the input end of the H-type bridge circuit are voltage-reduced, the control module outputs a high-level signal to control the driving module to output a high-level signal to drive the high-side switch module at the output end of the H-type bridge circuit to be fully turned on; When only the high side switch module and the freewheeling switch module at the output end of the H-type bridge circuit are boosted, the control module outputs a high level signal to control the driving module to output a high level signal to drive the high side switch module at the input end of the H-type bridge circuit to be fully turned on.

3. The high-efficiency buck-boost circuit according to claim 1, characterized in that: The power module also includes an LC filter circuit; The positive pole of the motor power supply is connected to an LC filter circuit and then to the high-side switch module at the input end of the H-type bridge circuit; a first inductor L1 is electrically connected between the output end of the high-side switch module at the input end of the H-type bridge circuit and the input end of the high-side switch module at the output end of the H-type bridge circuit.

4. The high-efficiency buck-boost circuit according to claim 1, characterized in that: The sampling module includes an input current and voltage sampling circuit, an output current and voltage sampling circuit, and an output current comparison circuit; The input current and voltage sampling circuit comprises an input current sampling circuit and an input voltage sampling circuit; The input current sampling circuit includes an input current sampling chip IC2 and an input current sampling resistor R42, wherein the input current sampling resistor R42 is electrically connected to the voltage output end of the motor; the input current sampling chip IC2 collects the current signal flowing through the input current sampling resistor R42 and outputs it to the corresponding signal input end of the control module; The input voltage sampling circuit includes an input voltage sampling chip U6, the positive phase end of the input voltage sampling chip U6 is connected to the positive pole of the motor power supply, the negative phase end of the input voltage sampling chip U6 is connected to the negative pole of the motor power supply, and the output end of the input voltage sampling chip U6 is connected to the corresponding signal input end of the control module; The output current and voltage sampling circuit comprises an output current sampling circuit and an output voltage sampling circuit; The output current sampling circuit includes an output current sampling chip IC1 and an output current sampling resistor R2, wherein the output current sampling resistor R2 is electrically connected to the voltage input terminal of the battery; the output current sampling chip IC1 collects the current signal flowing through the output current sampling resistor R2 and outputs it to the corresponding signal input terminal of the control module; The output voltage sampling circuit includes an output voltage sampling chip U7, the positive phase end of the output voltage sampling chip U7 is connected to the positive electrode of the battery, the negative phase end of the output voltage sampling chip U7 is connected to the negative electrode of the battery, and the output end of the output voltage sampling chip U7 is connected to the corresponding signal input end of the control module; The output current comparison circuit includes a comparison chip IC10A, the positive phase end of the comparison chip IC10A is connected to the current signal output end of the output current sampling circuit, the negative phase end of the comparison chip IC10A inputs a set current value, and the output end of the comparison chip IC10A is connected to the corresponding signal input end of the driving module.

5. The high-efficiency buck-boost circuit according to claim 1, characterized in that: The driving module includes a first switch driver U2, a second switch driver U4 and a logic circuit U5, wherein the logic AND gate circuit U5 is connected to the control module, and the first switch driver U2 and the second switch driver U4 are respectively connected to the logic AND gate circuit U5; A buck-boost control signal output terminal of the first switch driver U2 is connected to the buck-boost control terminal of the high-side switch module at the input end of the H-type bridge circuit, and another buck-boost control signal output terminal of the first switch driver U2 is connected to the buck-boost control terminal of the freewheeling switch module at the input end of the H-type bridge circuit; the high-side power supply terminal of the first switch driver U2 is connected to the voltage output terminal of the high-side power supply module; the power supply terminal of the first switch driver U2 is connected to the output terminal of the high-side switch module at the input end of the H-type bridge circuit; A buck-boost control signal output terminal of the second switch driver U4 is connected to the buck-boost control terminal of the high-side switch module at the output end of the H-type bridge circuit, and another buck-boost control signal output terminal of the second switch driver U4 is connected to the buck-boost control terminal of the freewheeling switch module at the output end of the H-type bridge circuit; the high-side power supply terminal of the second switch driver U4 is connected to the voltage output terminal of the high-side power supply module; the power supply terminal of the second switch driver U4 is connected to the input terminal of the high-side switch module at the output end of the H-type bridge circuit.

6. The high-efficiency buck-boost circuit according to claim 1, characterized in that: The high-side power supply module includes a current and voltage amplification module and a transformer T1, and the transformer T1 includes two sets of secondary coils; The PWM signal output end of the control module is connected to the electrical signal input end of the current and voltage amplification module, and its voltage output end is connected to the transformer T1. The voltage output end of the first group of secondary coils of the transformer T1 is connected to the high-side power supply end of the driving module, and the voltage output end of the second group of secondary coils of the transformer T1 is connected to the high-side power supply end of the driving module.

7. The high-efficiency buck-boost circuit according to claim 1, characterized in that: It also includes a power module, which provides power to the power-consuming module of the high-efficiency buck-boost circuit.

8. The high-efficiency buck-boost circuit according to claim 1, characterized in that: It also includes a communication module, which is communicatively connected with the control module.

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