Bidirectional charging and discharging circuit

Abstract

The utility model discloses a bidirectional charging and discharging circuit, which belongs to the technical field of electric energy conversion and comprises a bidirectional direct current / direct current conversion module, a first power supply module, a second power supply module, a third power supply module, a digital signal processor (DSP) module and a driving module. A second end of the bidirectional DC / DC conversion module is connected in parallel with two ends of the battery; two ends of the battery are connected in parallel with a first end of the first power supply module, a second end of the first power supply module is connected in parallel with a first end of the third power supply module, a second end of the third power supply module is connected in parallel with a first end of the DSP module, a second end of the DSP module is connected in parallel with a first end of the driving module, and a second end of the driving module is connected in parallel with a third end of the bidirectional DC / DC conversion module. The second end of the second power supply module is connected in parallel with the third end of the driving module. The utility model can realize two-way transmission of electric energy, and has a wide application range.

Description

Technical Field

[0001] The utility model relates to the technical field of electric energy conversion, and in particular to a bidirectional charging and discharging circuit. Background Art

[0002] Existing energy storage devices can output power through lithium batteries to provide power supply for electrical devices. After the power of the lithium battery is used up, an external power supply is needed to charge the lithium battery pack. Among them, the bidirectional charging and discharging circuit is the key circuit of the energy storage device. Utility Model Content

[0003] The utility model aims to provide a high-efficiency bidirectional charging and discharging circuit.

[0004] In order to achieve the above-mentioned purpose, the technical solution of the utility model is:

[0005] A bidirectional charging and discharging circuit comprises a bidirectional DC / DC conversion module, a first power module, a second power module, a third power module, a DSP module and a driving module, wherein a first end of the bidirectional DC / DC conversion module is connected to an external DC power, and a second end of the bidirectional DC / DC conversion module is connected in parallel to two ends of a battery; two ends of the battery are connected in parallel to a first end of the first power module, a second end of the first power module is connected in parallel to a first end of the third power module, a second end of the third power module is connected in parallel to a first end of the DSP module, a second end of the DSP module is connected in parallel to a first end of the driving module, and a second end of the driving module is connected in parallel to a third end of the bidirectional DC / DC conversion module; two ends of the battery are connected in parallel to a first end of the second power module, and a second end of the second power module is connected in parallel to a third end of the driving module.

[0006] The above-mentioned bidirectional charging and discharging circuit further includes a sampling module, a first end of the sampling module is connected in parallel to the fourth end of the bidirectional DC / DC conversion module, and a second end of the sampling module is connected in parallel to the third end of the DSP module.

[0007] The bidirectional DC / DC conversion module comprises a first switch, a second switch, a first inductor, a first capacitor and a second capacitor. The positive terminal of the first end of the bidirectional DC / DC conversion module is connected to the drain of the first switch and the first end of the first capacitor, the source of the first switch is connected to the first end of the first inductor, the second end of the first inductor is connected to the first end of the second capacitor, the second end of the second capacitor is connected to the second end of the first capacitor, the drain of the second switch is connected to the first end of the first inductor, the source of the second switch is connected to the second end of the first capacitor, the second end of the first inductor is connected to the positive electrode of the battery, and the second end of the second capacitor is connected to the negative electrode of the battery.

[0008] The above-mentioned bidirectional DC / DC conversion module also includes a first resistor and a second resistor, the first end of the first resistor is connected to the positive terminal of the first end of the bidirectional DC / DC conversion module, the second end of the first resistor is connected to the first end of the second resistor, and the second end of the second resistor is connected to the negative terminal of the first end of the bidirectional DC / DC conversion module.

[0009] The above-mentioned bidirectional DC / DC conversion module also includes a third resistor and a fourth resistor, the second end of the second resistor is connected to the first end of the third resistor, and the second end of the third resistor is connected to the second end of the first capacitor; the first end of the fourth resistor is connected to the second end of the second capacitor, and the second end of the fourth resistor is connected to the negative electrode of the battery.

[0010] The above-mentioned bidirectional DC / DC conversion module also includes a fifth resistor and a sixth resistor, the first end of the fifth resistor is connected to the second end of the first inductor, the second end of the fifth resistor is connected to the first end of the sixth resistor, and the second end of the sixth resistor is connected to the negative electrode of the battery.

[0011] The above-mentioned bidirectional DC / DC conversion module also includes a seventh resistor and a third capacitor, the first end of the seventh resistor is connected to the positive electrode of the battery, the second end of the seventh resistor is connected to the first end of the third capacitor, and the second end of the third capacitor is connected to the negative electrode of the battery.

[0012] In a specific embodiment, the first power module adopts chip SY7072.

[0013] In a specific embodiment, the second power module adopts chip AP3012.

[0014] In a specific embodiment, the third power module adopts chip JW7830-33.

[0015] Beneficial effect: the utility model is a bidirectional charging and discharging circuit, which can realize bidirectional transmission of electric energy; at the same time, it can directly convert the voltage of the lithium battery into the power supply required by each module; it can also convert the voltage of the lithium battery into a suitable voltage to power external devices; it has a wide range of applications.

[0016] In order to make the above features and advantages of the utility model more obvious and easy to understand, embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The utility model is a schematic diagram of the structure of a bidirectional charging and discharging circuit.

[0018] Figure 2 for Figure 1 A schematic diagram of a specific embodiment of a bidirectional DC / DC conversion module in FIG.

[0019] Figure 3 for Figure 1 A schematic diagram of a specific embodiment of the first power module in FIG.

[0020] Figure 4 for Figure 1 A schematic diagram of a specific embodiment of the second power module in FIG.

[0021] Figure 5 for Figure 1 A schematic diagram of a specific embodiment of the third power module in FIG. DETAILED DESCRIPTION

[0022] In order to make the purpose and technical solution of the embodiment of the utility model clearer, the technical solution of the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings of the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. Based on the described embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0023] Figure 1 This is a schematic diagram of the structure of a bidirectional charging and discharging circuit of the utility model. Figure 1 As shown, the utility model is a bidirectional charging and discharging circuit, including a bidirectional DC / DC conversion module 11, a first power module 12, a second power module 13, a third power module 14, a DSP module 15, a driving module 16 and a sampling module 17. The first end of the bidirectional DC / DC conversion module 11 includes a terminal V O1+ With terminal V O1- The first end of the bidirectional DC / DC conversion module 11 is connected to the external DC power, and the second end of the bidirectional DC / DC conversion module 11 is connected in parallel to the two ends of the battery BT, and the positive electrode of the battery BT is the terminal V B+ , the negative terminal of the battery BT is V B- The two ends of the battery BT are connected in parallel to the first end of the first power module 12, and the second end of the first power module 12 includes a terminal V O2+ With terminal V O2- The second end of the first power module 12 is connected in parallel to the first end of the third power module 14, and the second end of the third power module 14 includes a terminal V O5+ With terminal V O5-The second end of the third power module 14 is connected in parallel to the first end of the DSP module 15, the second end of the DSP module 15 is connected in parallel to the first end of the driving module 16, the second end of the driving module 16 is connected in parallel to the third end of the bidirectional DC / DC conversion module 11; the two ends of the battery BT are connected in parallel to the first end of the second power module 13, the second end of the second power module 13 includes a terminal V O4+ With terminal V O4- The second end of the second power supply module 13 is connected in parallel to the third end of the driving module 16; the first end of the sampling module 17 is connected in parallel to the fourth end of the bidirectional DC / DC conversion module 11, and the second end of the sampling module 17 is connected in parallel to the third end of the DSP module 15.

[0024] When the battery BT is discharged, the voltage V B The bidirectional DC / DC conversion module 11 converts the DC voltage V O1 Output to external electrical equipment; when charging the battery BT, the external DC power is converted by the bidirectional DC / DC conversion module 11 and then output to the battery BT, thereby realizing bidirectional transmission of electrical energy.

[0025] Furthermore, the first power module 17 converts the voltage V B Converted to voltage V O2 Output to the third power module 14, and then converted into a voltage V by the third power module 14 O5 , to supply power to the DSP module 15. The DSP module 15 generates a driving signal which drives the switch in the bidirectional DC / DC conversion module 11 through the driving module 16 to adjust the output voltage.

[0026] Furthermore, the first power module 12 can also convert the voltage V B Converted to voltage V O3 , the voltage V O3 It can power external low-power devices, such as communication units (DTU) and other devices.

[0027] Furthermore, the second power module 13 converts the voltage V B Converted to voltage V O4 The driving module 16 is powered.

[0028] Furthermore, the sampling module 17 samples the voltage and current information in the bidirectional DC / DC conversion module 11 and outputs the samples to the DSP module 15 , so that the DSP module 15 processes the voltage and current information to adjust the driving signal.

[0029] In a specific embodiment, the driving module 16 includes a driving chip. Optionally, the model of the driving chip is JW9610.

[0030] Figure 2 Show Figure 1 FIG. 1 is a schematic diagram of a specific embodiment of a bidirectional DC / DC conversion module 11. Figure 2 As shown, the terminal V O1+ The drain of the switch Q1 is connected to the first end of the capacitor C1, the source of the switch Q1 is connected to the first end of the inductor L1, the second end of the capacitor C1 is grounded, the second end of the inductor L1 is connected to the first end of the capacitor C2, the second end of the capacitor C2 is grounded, the drain of the switch Q2 is connected to the first end of the inductor L1, the source of the switch Q2 is grounded, the second end of the inductor L1 is connected to the first end of the fuse F1, and the second end of the fuse F1 is connected to the terminal V B+ .

[0031] Furthermore, the first end of the resistor R1 is connected to the terminal V O1+ The second end of the resistor R1 is connected to the first end of the resistor R2, and the second end of the resistor R2 is connected to the terminal V O1- , the terminal V O1- A first end of the resistor R3 is connected, and a second end of the resistor R3 is connected to a second end of the capacitor C1.

[0032] Furthermore, the first end of the resistor R5 is connected to the second end of the inductor L1, the second end of the resistor R5 is connected to the first end of the resistor R6, and the second end of the resistor R6 is connected to the terminal V B- The first end of the resistor R4 is connected to the second end of the capacitor C2, and the second end of the resistor R4 is connected to the terminal V B- The first end of the resistor R7 is connected to the first end of the fuse F1, the second end of the resistor R7 is connected to the first end of the capacitor C3, and the second end of the capacitor C3 is connected to the terminal V B- .

[0033] More specifically, the resistor R3 and the resistor R4 are current sampling resistors. The current flowing through the resistor R3 and the resistor R4 is amplified by the operational amplifier in the sampling module 17 and then fed back to the DSP module 15 so that the DSP module 15 can process it.

[0034] More specifically, the resistor R1 and the resistor R2 are used to detect the voltage at the first end of the bidirectional DC / DC conversion module 11, which is filtered by the RC filter in the sampling module 17 and fed back to the DSP module 15 so that the DSP module 15 can process it.

[0035] Optionally, the switch Q1 and the switch Q2 are N-type MOSFETs.

[0036] More specifically, the resistor R5 and the resistor R6 are used to detect the voltage at the second end of the bidirectional DC / DC conversion module 11, which is filtered by the RC filter in the sampling module 17 and fed back to the DSP module 15 so that the DSP module 15 can process it.

[0037] More specifically, the resistor R7 and the capacitor C3 function to reduce the peak when the battery BT is connected.

[0038] Figure 3 Show Figure 1 Schematic diagram of a specific embodiment of the first power module 12, wherein the first power module 12 acts as a voltage booster to increase the voltage V of the battery BT B Increase to voltage V O2 and voltage V O3 Output. Figure 3 As shown, the first power module 12 uses a chip SY7072, and the pin LX of the chip SY7072 is connected to the terminal V through an inductor L2. B+ , the terminal V B+ Through capacitor C4 to ground, the terminal V B+ The capacitor C5 is grounded, the GND pin of the chip SY7072 is grounded, and the IN pin of the chip SY7072 is connected to the terminal V B+ , the pin IN of the chip SY7072 is grounded through the capacitor C6, the pin EN of the chip SY7072 is grounded through the capacitor C6, the pin OUT of the chip SY7072 is connected to the first end of the resistor R8, the second end of the resistor R8 is connected to the first end of the resistor R9, the second end of the resistor R9 is grounded, the second end of the resistor R8 is connected to the pin FB of the chip SY7072, the pin OUT of the chip SY7072 is connected to the first end of the capacitor C7, the second end of the capacitor C7 is connected to the second end of the resistor R8, the pin OUT of the chip SY7072 is grounded through the capacitor C8, the pin OUT of the chip SY7072 is grounded through the capacitor C9, and the pin OUT of the chip SY7072 is the terminal V O2+ The pin OUT of the chip SY7072 is connected to the anode of the diode D1, and the cathode of the diode D1 is the terminal V O3+ .

[0039] More specifically, the capacitor C4 and the capacitor C5 are input capacitors.

[0040] More specifically, the capacitor C6 is a decoupling capacitor of the chip SY7072.

[0041] More specifically, by setting the voltage division ratio of the resistor R8 and the resistor R9, the output voltage V O2 With voltage V O3 At the same time, the output voltage is fed back to the chip SY7072. The capacitor C7 plays a feedforward role.

[0042] More specifically, the capacitor C8 and the capacitor C9 are output capacitors.

[0043] Figure 4 Show Figure 1 The second power module 13 is a schematic diagram of a specific embodiment of the invention, wherein the second power module 13 acts as a voltage booster to increase the voltage V of the battery BT. B Increase to voltage V O4 Output. Figure 4 As shown, the second power module 13 uses a chip AP3012, and the pin VIN of the chip AP3012 is connected to the terminal V B+ , the terminal V B+ Through capacitor C10 grounded, the terminal V B+ The pin VIN of the chip AP3012 is connected to the pin SW of the chip AP3012 through the capacitor C11, and the pin SHDM of the chip AP3012 is connected to the control signal G1 from the DSP module 15 through the resistor R10. The control signal G1 controls the opening or closing of the chip AP3012. The pin SW of the chip AP3012 is also connected to the anode of the diode D2, and the cathode of the diode D2 is the terminal V O4+ , the terminal V O4+ The first end of the resistor R11 is connected to the second end of the resistor R11, the first end of the resistor R12 is connected to the second end of the resistor R12, the second end of the resistor R12 is grounded GND, and the terminal V O4+ Through capacitor C13 grounded, the terminal V O4+ The pin GND of the chip AP3012 is grounded through the capacitor C12, and the pin FB of the chip AP3012 is connected to the first end of the resistor R12.

[0044] More specifically, the capacitor C10 and the capacitor C11 are input capacitors.

[0045] More specifically, the diode D2 is a rectifier diode.

[0046] More specifically, by setting the voltage division ratio of the resistor R11 and the resistor R12, the output voltage V can be adjusted. O4 At the same time, the output voltage is fed back to the chip AP3012.

[0047] More specifically, the capacitor C12 and the capacitor C13 are output capacitors.

[0048] More specifically, the resistor R10 is a current limiting resistor.

[0049] Figure 5 Show Figure 1 The third power module 14 is a schematic diagram of a specific embodiment of the third power module 14, wherein the third power module 14 plays a role of stepping down the voltage V O2 Reduced to voltage V O5 Output. Figure 5 As shown, the third power module 14 uses a chip JW7830-33, and the pin VIN of the chip JW7830-33 is connected to the terminal V O2+ The pin VIN of the chip JW7830-33 is grounded through the capacitor C14, the pin VIN of the chip JW7830-33 is grounded through the capacitor C15, and the pin VOUT of the chip JW7830-33 is the terminal V O5+ The pin VOUT of the chip JW7830-33 is grounded through the capacitor C16, the pin VOUT of the chip JW7830-33 is grounded through the capacitor C17, and the pin GND of the chip JW7830-33 is grounded.

[0050] In a specific embodiment, the voltage V O1 is 12V, the voltage V O2 is 5V, the voltage V O3 is 5V, the voltage V O4 is 10V, the voltage V O5 is 3.3V.

[0051] Although the present invention has been disclosed as above by the embodiments, it is not intended to limit the present invention. Any person with ordinary knowledge in the technical field can make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be determined by the scope of the attached patent application.

Claims

1. A bidirectional charge and discharge circuit, characterized in that: The invention comprises a bidirectional DC / DC conversion module (11), a first power module (12), a second power module (13), a third power module (14), a DSP module (15) and a driving module (16); a first end of the bidirectional DC / DC conversion module (11) is connected to an external DC power, and a second end of the bidirectional DC / DC conversion module (11) is connected in parallel to two ends of a battery; two ends of the battery are connected in parallel to the first end of the first power module (12), a second end of the first power module (12) is connected in parallel to the first end of the third power module (14), a second end of the third power module (14) is connected in parallel to the first end of the DSP module (15), a second end of the DSP module (15) is connected in parallel to the first end of the driving module (16), and a second end of the driving module (16) is connected in parallel to the third end of the bidirectional DC / DC conversion module (11); two ends of the battery are connected in parallel to the first end of the second power module (13), and a second end of the second power module (13) is connected in parallel to the third end of the driving module (16).

2. A bidirectional charge and discharge circuit as claimed in claim 1, characterized in that: It also includes a sampling module (17), wherein a first end of the sampling module (17) is connected in parallel to a fourth end of the bidirectional DC / DC conversion module (11), and a second end of the sampling module (17) is connected in parallel to a third end of the DSP module (15).

3. A bidirectional charge and discharge circuit as claimed in claim 2, characterized in that: The bidirectional DC / DC conversion module (11) comprises a first switch (Q1), a second switch (Q2), a first inductor (L1), a first capacitor (C1) and a second capacitor (C2); the positive terminal of the first end of the bidirectional DC / DC conversion module (11) is connected to the drain of the first switch (Q1) and the first end of the first capacitor (C1); the source of the first switch (Q1) is connected to the first end of the first inductor (L1); the second end of the first inductor (L1) is connected to the first end of the second capacitor (C2); the second end of the second capacitor (C2) is connected to the second end of the first capacitor (C1); the drain of the second switch (Q2) is connected to the first end of the first inductor (L1); the source of the second switch (Q2) is connected to the second end of the first capacitor (C1); the second end of the first inductor (L1) is connected to the positive electrode of the battery; and the second end of the second capacitor (C2) is connected to the negative electrode of the battery.

4. A bidirectional charge and discharge circuit as claimed in claim 3, characterized in that: The bidirectional DC / DC conversion module further comprises a first resistor (R1) and a second resistor (R2), wherein the first end of the first resistor (R1) is connected to the positive terminal of the first end of the bidirectional DC / DC conversion module (11), the second end of the first resistor (R1) is connected to the first end of the second resistor (R2), and the second end of the second resistor (R2) is connected to the negative terminal of the first end of the bidirectional DC / DC conversion module (11).

5. A bidirectional charge and discharge circuit as claimed in claim 4, characterized in that: The bidirectional DC / DC conversion module (11) further comprises a third resistor (R3) and a fourth resistor (R4), wherein the second end of the second resistor (R2) is connected to the first end of the third resistor (R3), and the second end of the third resistor (R3) is connected to the second end of the first capacitor (C1); the first end of the fourth resistor (R4) is connected to the second end of the second capacitor (C2), and the second end of the fourth resistor (R4) is connected to the negative electrode of the battery.

6. A bidirectional charge and discharge circuit as claimed in claim 5, characterized in that: The bidirectional DC / DC conversion module (11) further comprises a fifth resistor (R5) and a sixth resistor (R6), wherein the first end of the fifth resistor (R5) is connected to the second end of the first inductor (L1), the second end of the fifth resistor (R5) is connected to the first end of the sixth resistor (R6), and the second end of the sixth resistor (R6) is connected to the negative electrode of the battery.

7. A bidirectional charge and discharge circuit as claimed in claim 6, characterized in that: The bidirectional DC / DC conversion module (11) further comprises a seventh resistor (R7) and a third capacitor (C3), wherein a first end of the seventh resistor (R7) is connected to the positive electrode of the battery, a second end of the seventh resistor (R7) is connected to the first end of the third capacitor (C3), and a second end of the third capacitor (C3) is connected to the negative electrode of the battery.

8. A bidirectional charge and discharge circuit as claimed in claim 7, characterized in that: The first power module (12) uses a chip SY7072.

9. A bidirectional charge and discharge circuit as claimed in claim 8, characterized in that: The second power module (13) uses chip AP3012.

10. A bidirectional charge and discharge circuit as claimed in claim 9, characterized in that: The third power module (14) uses a chip JW7830-33.

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