High-voltage battery pack voltage reduction circuit and high-voltage electric motorcycle battery

Abstract

The high-voltage battery pack voltage reduction circuit comprises a high-voltage voltage reduction module and a voltage reduction output module; the high-voltage voltage reduction module comprises a voltage reduction electronic switch tube, a voltage reduction stabilizing tube and a first resistor, the control end of the voltage reduction electronic switch tube is used for being connected with the non-end voltage node of the high-voltage battery pack; the control end of the voltage reduction electronic switch tube is also connected with the negative electrode of the voltage reduction stabilizing tube, and the positive electrode of the voltage reduction stabilizing tube is connected with the second end of the voltage reduction electronic switch tube. When the non-end voltage node of the high-voltage battery pack is connected, after the voltage between the two ends of the voltage reduction stabilizing tube is stabilized, the voltage reduction electronic switch tube is turned on, the output voltage is clamped and reduced by the voltage reduction stabilizing tube, so that the output voltage on the first end of the first capacitor is lower than the positive electrode voltage of the high-voltage battery pack, and the circuit structure is simple under the condition of meeting the low-voltage output, and the cost is effectively reduced.

Description

Technical Field

[0001] This disclosure relates to the field of battery technology, and in particular to a high-voltage battery pack step-down circuit and a high-voltage electric motorcycle battery. Background Technology

[0002] Traditional high-voltage electric motorcycle battery management systems (BMS) are prone to voltage stress breakdown of the switching power supply chip and low-voltage linear regulator (LDO) used for voltage reduction in high-voltage scenarios (such as DC 100V or higher). To power the switching power supply chip and LDO, the battery voltage needs to be stepped down to 100V or lower. Since most traditional switching power supply chips have a withstand voltage below 100V, and the LDO needs to convert voltages exceeding 100V to 5V or lower, a high-voltage BMS requires a step-down circuit to reduce the input voltage of the switching power supply chip and LDO to below 100V.

[0003] However, there are two main traditional methods for converting high voltage to medium and low voltage: one is to use a transformer circuit, but transformers are too large and the circuit is too complex; the other is to use a high voltage conversion chip, which does not require an extra circuit structure, but such chips are too expensive. Utility Model Content

[0004] The purpose of this disclosure is to overcome the shortcomings of the prior art and provide a high-voltage battery pack step-down circuit with a simple and low-cost step-down circuit structure, as well as a high-voltage electric motorcycle battery.

[0005] The purpose of this disclosure is achieved through the following technical solution:

[0006] A high-voltage battery pack step-down circuit includes: a high-voltage step-down module and a step-down output module; the high-voltage step-down module includes a step-down electronic switch, a step-down Zener diode, and a first resistor, a first terminal of the first resistor being connected to the positive terminal of the high-voltage battery pack, a second terminal of the first resistor being connected to the first terminal of the step-down electronic switch, and a control terminal of the step-down electronic switch being connected to a non-terminal voltage node of the high-voltage battery pack; the control terminal of the step-down electronic switch is also connected to the negative terminal of the step-down Zener diode, and the positive terminal of the step-down Zener diode is connected to the second terminal of the step-down electronic switch; the step-down output module includes a second resistor and a first capacitor, a second terminal of the step-down electronic switch being connected to the first terminal of the second resistor, a second terminal of the second resistor being connected to the negative terminal of the high-voltage battery pack, a first terminal of the first capacitor being connected to the first terminal of the second resistor, and a second terminal of the first capacitor being connected to the second terminal of the second resistor, wherein the first terminal of the first capacitor is used to output the stepped-down voltage.

[0007] In one embodiment, the voltage regulation value of the step-down regulator is greater than or equal to the turn-on voltage of the step-down electronic switch.

[0008] In one embodiment, the step-down electronic switch is an NPN MOS transistor.

[0009] In one embodiment, the high-voltage buck module further includes a third resistor, the first end of which is used to connect to a non-end voltage node, and the second end of which is connected to the control terminal of the buck electronic switch.

[0010] In one embodiment, both the first resistor and the third resistor are adjustable resistors.

[0011] In one embodiment, the high-voltage step-down module further includes a back-drain diode, with the second terminal of the first resistor connected to the positive terminal of the back-drain diode and the negative terminal of the back-drain diode connected to the first terminal of the step-down electronic switch.

[0012] In one embodiment, the buck output module further includes a fourth resistor and a second capacitor. The second end of the second resistor is connected to the negative terminal of the high-voltage battery pack through the fourth resistor. The second end of the first capacitor is connected to the negative terminal of the high-voltage battery pack through the second capacitor. The second end of the first capacitor is also connected to the second end of the second resistor.

[0013] In one embodiment, the buck output module further includes a third capacitor, the second terminal of the buck electronic switch is connected to the first terminal of the third capacitor, and the second terminal of the third capacitor is connected to the negative terminal of the high-voltage battery pack.

[0014] In one embodiment, the third capacitor is an adjustable capacitor.

[0015] A high-voltage electric motorcycle battery includes a high-voltage battery pack step-down circuit as described in any of the above claims.

[0016] Compared with the prior art, this disclosure has at least the following advantages:

[0017] When a non-terminal voltage node of a high-voltage battery pack is connected, the turn-on of the buck electronic switch is determined by the magnitude of the current flowing into the buck regulator. After the voltage across the buck regulator stabilizes, the buck electronic switch turns on. Since the positive voltage of the high-voltage battery pack is applied to the first terminal of the buck electronic switch to provide a continuous output current, and the output voltage is clamped and reduced by the buck regulator, the output voltage at the first terminal of the first capacitor is lower than the positive voltage of the high-voltage battery pack. This buck circuit has a simple circuit structure and effectively reduces costs while meeting the requirements of low voltage output. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of this disclosure, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of this disclosure and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a circuit diagram of a high-voltage battery pack step-down circuit in one embodiment;

[0020] Figure 2 This is a circuit diagram of a high-voltage step-down module in one embodiment;

[0021] Figure 3 This is a circuit diagram of a step-down output module in one embodiment. Detailed Implementation

[0022] To facilitate understanding of this disclosure, a more complete description will be given below with reference to the accompanying drawings, which illustrate preferred embodiments of the present disclosure. However, this disclosure can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure.

[0023] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of this disclosure. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0025] This disclosure relates to a high-voltage battery pack step-down circuit. In one embodiment, the high-voltage battery pack step-down circuit includes a high-voltage step-down module and a step-down output module; the high-voltage step-down module includes a step-down electronic switch, a step-down Zener diode, and a first resistor, a first terminal of the first resistor being connected to the positive terminal of the high-voltage battery pack, a second terminal of the first resistor being connected to the first terminal of the step-down electronic switch, and a control terminal of the step-down electronic switch being connected to a non-terminal voltage node of the high-voltage battery pack; the control terminal of the step-down electronic switch is also connected to the negative terminal of the step-down Zener diode, and the positive terminal of the step-down Zener diode is connected to the second terminal of the step-down electronic switch; the step-down output module includes a second resistor and a first capacitor, a second terminal of the step-down electronic switch being connected to the first terminal of the second resistor, a second terminal of the second resistor being connected to the negative terminal of the high-voltage battery pack, a first terminal of the first capacitor being connected to the first terminal of the second resistor, and a second terminal of the first capacitor being connected to the second terminal of the second resistor, wherein the first terminal of the first capacitor is used to output the stepped-down voltage. When a non-terminal voltage node of a high-voltage battery pack is connected, the turn-on of the buck electronic switch is determined by the magnitude of the current flowing into the buck regulator. After the voltage across the buck regulator stabilizes, the buck electronic switch turns on. Since the positive voltage of the high-voltage battery pack is applied to the first terminal of the buck electronic switch to provide a continuous output current, and the output voltage is clamped and reduced by the buck regulator, the output voltage at the first terminal of the first capacitor is lower than the positive voltage of the high-voltage battery pack. This buck circuit has a simple circuit structure and effectively reduces costs while meeting the requirements of low voltage output.

[0026] Please see Figure 1 This is a circuit diagram of a high-voltage battery pack step-down circuit according to an embodiment of the present disclosure.

[0027] One embodiment of the high-voltage battery pack step-down circuit 10 includes a high-voltage step-down module 100 and a step-down output module 200. Please refer to both. Figure 2 The high-voltage buck module 100 includes a buck electronic switch MP1, a buck regulator ZP2, and a first resistor RP1. The first terminal of the first resistor RP1 is connected to the positive terminal B+ of the high-voltage battery pack, and the second terminal of the first resistor RP1 is connected to the first terminal of the buck electronic switch MP1. The control terminal of the buck electronic switch MP1 is connected to the non-end voltage node Bn of the high-voltage battery pack. The control terminal of the buck electronic switch MP1 is also connected to the negative terminal of the buck regulator ZP2, and the positive terminal of the buck regulator ZP2 is connected to the second terminal of the buck electronic switch MP1. Please refer to the following: Figure 3 The step-down output module 200 includes a second resistor RP5 and a first capacitor CP5. The second terminal of the step-down electronic switch MP1 is connected to the first terminal of the second resistor RP5. The second terminal of the second resistor RP5 is connected to the negative terminal B- of the high-voltage battery pack. The first terminal of the first capacitor CP5 is connected to the first terminal of the second resistor RP5. The second terminal of the first capacitor CP5 is connected to the second terminal of the second resistor RP5. The first terminal of the first capacitor CP5 is used to output the stepped-down voltage.

[0028] In this embodiment, when the non-end voltage node Bn of the high-voltage battery pack is connected, the turn-on of the buck electronic switch MP1 is determined by the magnitude of the current flowing into the buck regulator ZP2. After the voltage across the buck regulator ZP2 stabilizes, the buck electronic switch MP1 turns on. Since the positive terminal B+ voltage of the high-voltage battery pack is applied to the first terminal of the buck electronic switch MP1 to provide a continuous output current, and the output voltage is clamped and reduced by the buck regulator ZP2, the output voltage at the first terminal of the first capacitor CP5 is lower than the positive terminal B+ voltage of the high-voltage battery pack. This buck circuit has a simple circuit structure and effectively reduces costs while meeting the requirements of low voltage output.

[0029] In one embodiment, the voltage regulation value of the step-down regulator ZP2 is greater than or equal to the turn-on voltage of the step-down electronic switch MP1. In this embodiment, the step-down regulator ZP2 is connected in parallel between the control terminal and the second terminal of the step-down electronic switch MP1. The step-down regulator ZP2 serves as a clamping device for the output voltage. Specifically, the positive terminal of the step-down regulator ZP2 is connected to a non-end voltage node Bn of the high-voltage battery pack. The non-end voltage node Bn is one of the nodes in the series-connected battery pack, that is, the node in the series-connected battery pack excluding the highest voltage node, or any node in the series-connected battery pack other than the highest voltage node. This makes the positive terminal voltage of the step-down regulator ZP2 lower than the positive terminal B+ voltage of the high-voltage battery pack. When the step-down regulator ZP2 reaches the regulated state, the step-down electronic switch MP1 reaches the turn-on voltage, which facilitates the timely conduction of the step-down electronic switch MP1 and also clamps and reduces the output voltage.

[0030] In one embodiment, the step-down electronic switch MP1 is an NPN MOS transistor, the first terminal of the step-down electronic switch MP1 is the drain of the NPN MOS transistor, the second terminal of the step-down electronic switch MP1 is the source of the NPN MOS transistor, and the control terminal of the step-down electronic switch MP1 is the gate of the NPN MOS transistor.

[0031] In one embodiment, please refer to Figure 2 The high-voltage step-down module 100 further includes a third resistor RP3. The first end of the third resistor RP3 is connected to a non-terminal voltage node, and the second end of the third resistor RP3 is connected to the control terminal of the step-down electronic switch MP1. In this embodiment, the third resistor RP3 is connected in series with the control terminal of the step-down electronic switch MP1. The third resistor RP3 limits the current flowing into the control terminal of the step-down electronic switch MP1 to ensure the stable operation of the step-down electronic switch MP1, and also prevents the reverse current of the step-down regulator ZP2 from exceeding the safe value.

[0032] In one embodiment, both the first resistor RP1 and the third resistor RP3 are adjustable resistors. In this embodiment, by adjusting the first resistor RP1 to control the first terminal current of the buck electronic switch MP1, and by adjusting the third resistor RP3 to control the control terminal current of the buck electronic switch MP1, the buck electronic switch MP1 is precisely controlled, and the buck electronic switch MP1 is controlled to continuously output the required load current after being turned on, avoiding current surges to the connected devices.

[0033] In one embodiment, please refer to Figure 2 The high-voltage buck module 100 further includes a backflow preventer diode DP1. The second terminal of the first resistor RP1 is connected to the positive terminal of the backflow preventer diode DP1, and the negative terminal of the backflow preventer diode DP1 is connected to the first terminal of the buck electronic switch MP1. In this embodiment, the backflow preventer diode DP1 is connected in series with the first terminal of the buck electronic switch MP1. The backflow preventer diode DP1 blocks the reverse current generated by the buck electronic switch MP1 when it is turned off, so as to prevent the reverse current on the first terminal of the buck electronic switch MP1 from impacting the positive terminal B+ voltage of the high-voltage battery pack, thereby ensuring the voltage output stability of the high-voltage battery pack.

[0034] In one embodiment, please refer to Figure 3 The step-down output module 200 further includes a fourth resistor RP6 and a second capacitor CP6. The second terminal of the second resistor RP5 is connected to the negative terminal B- of the high-voltage battery pack through the fourth resistor RP6. The second terminal of the first capacitor CP5 is also connected to the negative terminal B- of the high-voltage battery pack through the second capacitor CP6. The second terminal of the first capacitor CP5 is also connected to the second terminal of the second resistor RP5. In this embodiment, the fourth resistor RP6 and the second resistor RP5 are connected in series, forming a segmented loading of the output voltage. The second capacitor CP6 is connected in parallel with the fourth resistor RP6, and is also connected in series with the first capacitor CP5. This forms a voltage spike absorption circuit between the fourth resistor RP6 and the second capacitor CP6 to absorb the surge voltage from the instantaneous power-on of the positive terminal B+ of the high-voltage battery pack. Furthermore, the second resistor RP5 and the first capacitor CP5 form another voltage spike absorption circuit, creating a two-stage voltage spike absorption protection to prevent voltage pulses from affecting downstream connected appliances.

[0035] In one embodiment, please refer to Figure 3 The step-down output module 200 further includes a third capacitor CP7. The second terminal of the step-down electronic switch MP1 is connected to the first terminal of the third capacitor CP7, and the second terminal of the third capacitor CP7 is connected to the negative terminal B- of the high-voltage battery pack. In this embodiment, the third capacitor CP7 is connected in parallel to the second terminal of the step-down electronic switch MP1, so that the third capacitor CP7 acts as a filter capacitor to filter the output voltage, ensuring a more stable low output voltage. The third capacitor CP7 is an adjustable capacitor; by adjusting the capacitance value of the third capacitor CP7, it is possible to filter out noise voltages of different frequencies in the stepped-down voltage, thereby further improving the stability of the stepped-down voltage output.

[0036] In one embodiment, this disclosure also provides a high-voltage electric motorcycle battery, including the high-voltage battery pack step-down circuit described in any of the above embodiments. In this embodiment, the high-voltage battery pack step-down circuit includes a high-voltage step-down module and a step-down output module; the high-voltage step-down module includes a step-down electronic switch, a step-down Zener diode, and a first resistor, the first end of the first resistor is connected to the positive terminal of the high-voltage battery pack, the second end of the first resistor is connected to the first end of the step-down electronic switch, the control terminal of the step-down electronic switch is connected to a non-end voltage node of the high-voltage battery pack; the control terminal of the step-down electronic switch is also connected to the negative terminal of the step-down Zener diode, the positive terminal of the step-down Zener diode is connected to the second end of the step-down electronic switch; the step-down output module includes a second resistor and a first capacitor, the second end of the step-down electronic switch is connected to the first end of the second resistor, the second end of the second resistor is connected to the negative terminal B- of the high-voltage battery pack, the first end of the first capacitor is connected to the first end of the second resistor, and the second end of the first capacitor is connected to the second end of the second resistor, wherein the first end of the first capacitor is used to output the stepped-down voltage. When a non-terminal voltage node of a high-voltage battery pack is connected, the turn-on of the buck electronic switch is determined by the magnitude of the current flowing into the buck regulator. After the voltage across the buck regulator stabilizes, the buck electronic switch turns on. Since the positive voltage of the high-voltage battery pack is applied to the first terminal of the buck electronic switch to provide a continuous output current, and the output voltage is clamped and reduced by the buck regulator, the output voltage at the first terminal of the first capacitor is lower than the positive voltage of the high-voltage battery pack. This buck circuit has a simple circuit structure and effectively reduces costs while meeting the requirements of low voltage output.

[0037] The embodiments described above are merely illustrative of several implementations of this disclosure, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent disclosure. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this disclosure, and these all fall within the protection scope of this disclosure. Therefore, the protection scope of this patent disclosure should be determined by the appended claims.

Claims

1. A high-voltage battery pack step-down circuit, characterized in that, include: A high-voltage buck module includes a buck electronic switch, a buck Zener diode, and a first resistor. A first terminal of the first resistor is connected to the positive terminal of a high-voltage battery pack, and a second terminal of the first resistor is connected to the first terminal of the buck electronic switch. The control terminal of the buck electronic switch is connected to a non-terminal voltage node of the high-voltage battery pack. The control terminal of the buck electronic switch is also connected to the negative terminal of the buck Zener diode, and the positive terminal of the buck Zener diode is connected to the second terminal of the buck electronic switch. A step-down output module includes a second resistor and a first capacitor. The second terminal of the step-down electronic switch is connected to the first terminal of the second resistor. The second terminal of the second resistor is connected to the negative terminal of the high-voltage battery pack. The first terminal of the first capacitor is connected to the first terminal of the second resistor, and the second terminal of the first capacitor is connected to the second terminal of the second resistor. The first terminal of the first capacitor is used to output the stepped-down voltage.

2. The high-voltage battery pack step-down circuit according to claim 1, characterized in that, The voltage regulation value of the step-down regulator is greater than or equal to the turn-on voltage of the step-down electronic switch.

3. The high-voltage battery pack step-down circuit according to claim 1, characterized in that, The step-down electronic switch is an NPN type MOS transistor.

4. The high-voltage battery pack step-down circuit according to claim 1, characterized in that, The high-voltage step-down module also includes a third resistor, the first end of which is used to connect to a non-end voltage node, and the second end of which is connected to the control terminal of the step-down electronic switch.

5. The high-voltage battery pack step-down circuit according to claim 4, characterized in that, Both the first resistor and the third resistor are adjustable resistors.

6. The high-voltage battery pack step-down circuit according to claim 1, characterized in that, The high-voltage step-down module also includes a back-drain diode. The second terminal of the first resistor is connected to the positive terminal of the back-drain diode, and the negative terminal of the back-drain diode is connected to the first terminal of the step-down electronic switch.

7. The high-voltage battery pack step-down circuit according to claim 1, characterized in that, The step-down output module also includes a fourth resistor and a second capacitor. The second end of the second resistor is connected to the negative terminal of the high-voltage battery pack through the fourth resistor. The second end of the first capacitor is connected to the negative terminal of the high-voltage battery pack through the second capacitor. The second end of the first capacitor is also connected to the second end of the second resistor.

8. The high-voltage battery pack step-down circuit according to claim 1, characterized in that, The step-down output module also includes a third capacitor. The second terminal of the step-down electronic switch is connected to the first terminal of the third capacitor, and the second terminal of the third capacitor is connected to the negative terminal of the high-voltage battery pack.

9. The high-voltage battery pack step-down circuit according to claim 8, characterized in that, The third capacitor is an adjustable capacitor.

10. A high-voltage electric motorcycle battery, characterized in that, Includes a high-voltage battery pack step-down circuit as described in any one of claims 1 to 9.

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