Battery protection circuit and battery module of golf cart

Abstract

The utility model relates to the technical field of batteries, in particular to a battery protection circuit and a battery module of a golf cart, two ends of the battery protection circuit are respectively connected with a battery total positive interface P + and a battery total negative interface P-, the battery protection circuit comprises a plurality of protection capacitors C, two ends of each protection capacitor C are connected with a balance circuit in parallel, and each balance circuit comprises a consumption resistor R2 and a control circuit. And a switch element of the control circuit is connected in series with the consumption resistor R2 and controls the on-off of the balance circuit according to whether voltages at two ends of the protection capacitor C are higher than a set value. When the battery is fully charged, the charging switch is switched off, redundant feedback energy is used for charging the protection capacitor C connected in series, redundant electric energy is consumed through the consumption resistor R2, and damage to the protection capacitor C is avoided; and when the battery is not fully charged and the charging switch is connected, the protection capacitor C discharges, and the battery is automatically charged.

Description

TECHNICAL FIELD

[0001] The utility model relates to a battery technical field, concretely relates to a battery protection circuit and battery module of golf cart. BACKGROUND

[0002] The current golf cart application scene has continuous downhill. When driving downhill, the golf cart will charge the battery through the energy feedback system in addition to vehicle brake braking. When the battery circuit is full, the BMS (Battery Management System) charging switch will be disconnected to prevent overcharging of the battery cell. After the battery is disconnected, if the vehicle still has energy feedback during downhill driving, the part of the energy cannot be absorbed by the battery system, which is easy to cause damage to the vehicle motor system connected with the battery system. SUMMARY

[0003] The utility model discloses a utility model relates to a golf cart battery full, the problem that the excess feedback energy is easy to damage the vehicle motor system, provides a kind of battery protection circuit and battery module for the protection of golf cart vehicle motor system.

[0004] The utility model provides the technical scheme as follows: a kind of battery protection circuit of golf cart, the both ends of the battery protection circuit are connected battery total positive interface P+ and battery total negative interface P- respectively, the battery protection circuit includes several mutually connected sub-circuits, each sub-circuit includes:

[0005] Protection capacitor C, the protection capacitor C of different sub-circuits is mutually connected;

[0006] Balancing resistance R1 is connected in parallel at the both ends of protection capacitor C;

[0007] Balancing circuit, including consumption resistance R2 and control circuit, the switch element of control circuit is connected in series with consumption resistance R2 and is connected in parallel at the both ends of protection capacitor C, control circuit is coupled with protection capacitor C to collect the voltage at the both ends of protection capacitor C and according to whether the voltage at input end is higher than set value to control the on-off of switch element.

[0008] The balancing resistor R1 ensures the voltage balance across each protection capacitor C. When the battery is fully charged, the charging switch is turned off, and the excess feedback energy is used to charge the several series-connected protection capacitors C, avoiding damage to the vehicle motor system. When the voltage across the protection capacitor C is higher than the set value, the control circuit acquires this voltage, and the control switch element connects the balancing circuit, so that the consumption resistor R2 is connected across the protection capacitor C, and the excess energy is consumed, avoiding damage to the protection capacitor C. When the battery is not fully charged, and the charging switch is connected, the protection capacitor C discharges, automatically charging the battery, so that the voltage across the protection capacitor C is reduced to below the set value. The control circuit acquires this voltage, and the control switch element disconnects the balancing circuit, avoiding the consumption of the energy in the protection capacitor C by the consumption resistor R2, protecting the vehicle motor system while saving energy.

[0009] As a preferred embodiment, the control circuit comprises a transistor Q as a switch element, and a transistor on-off control circuit. The emitter E of the transistor Q is connected to the positive pole of the protection capacitor C, the collector L is connected to the consumption resistor R2, and the base B is connected to the output terminal of the transistor on-off control circuit. The sampling terminal of the transistor on-off control circuit is connected across the protection capacitor C, and controls the on-off of the transistor Q according to whether the voltage of the protection capacitor C is higher than the set value.

[0010] When the battery is fully charged, the charging switch is turned off, and the excess feedback energy is used to charge the several series-connected protection capacitors C. When the voltage across the protection capacitor C is higher than the set value, the sampling terminal of the transistor on-off control circuit detects this, and the output terminal of the transistor on-off control circuit transmits a current signal to the base B, so that the emitter E and the collector L of the transistor Q are turned on, and the consumption resistor R2 is connected across the protection capacitor C, and the excess energy is consumed, avoiding damage to the protection capacitor C. When the battery is not fully charged, and the charging switch is connected, the protection capacitor C discharges, automatically charging the battery, so that the voltage across the protection capacitor C is reduced to below the set value. The sampling terminal of the transistor on-off control circuit detects this, and the output terminal of the transistor on-off control circuit transmits a current signal to the base B, so that the emitter E and the collector L of the transistor Q are turned off, and the balancing circuit is disconnected, avoiding the consumption of the energy in the protection capacitor C by the consumption resistor R2.

[0011] As preferred, the triode on-off control circuit comprises a voltage stabilizing circuit and a voltage dividing circuit connected in parallel, the voltage stabilizing circuit comprises a voltage stabilizing resistor R3 and a three-terminal voltage regulator U, the anode 2 of the three-terminal voltage regulator U is connected to the positive pole of a protection capacitor C through the voltage stabilizing resistor R3, the base B of the triode Q is connected to the anode 2 of the three-terminal voltage regulator U, the cathode 3 of the three-terminal voltage regulator U is connected to the negative pole of the protection capacitor C, the sampling end of the voltage dividing circuit is coupled with the protection capacitor C, and the output end is connected to the reference end 1 of the three-terminal voltage regulator U, and the voltage dividing circuit controls the on-off of the three-terminal voltage regulator U according to whether the voltage of the protection capacitor C is higher than a set value.

[0012] When the voltage between the two ends of the protection capacitor C is lower than the set value, the voltage in the voltage dividing circuit is also lower than the set value, the anode 2 and the cathode 3 are kept disconnected, that is, the voltage stabilizing circuit is disconnected, so that there is no current signal on the base B, and the triode Q is kept disconnected, and the consumption resistor R2 does not consume electric energy;

[0013] When the battery is fully charged, the charging switch is disconnected, and the excess feedback energy is used to charge a plurality of series-connected protection capacitors C, when the voltage between the two ends of the protection capacitor C is higher than the set value, the sampling end of the voltage dividing circuit detects it, and the output end of the voltage dividing circuit outputs a current to the reference end 1 of the three-terminal voltage regulator U to control the anode 2 and the cathode 3 to be connected, so that the voltage stabilizing circuit is connected, thereby transmitting the current to the base B, so that the triode Q is turned on, and the consumption resistor R2 is connected to the two ends of the protection capacitor C, so that the excess electric energy is consumed.

[0014] As preferred, the voltage dividing circuit comprises a voltage dividing resistor R4 and a voltage dividing resistor R5 connected in series, and the output end of the voltage dividing circuit is located between the voltage dividing resistor R4 and the voltage dividing resistor R5, and the voltage or current signal output by the output end of the voltage dividing circuit is adjusted by the voltage dividing resistor R4 and the voltage dividing resistor R5 to match the model of the reference end 1 of the three-terminal voltage regulator U.

[0015] As preferred, the consumption resistor R2 comprises a plurality of resistors connected in parallel.

[0016] As preferred, the consumption resistor R2 further comprises a light emitting diode LED as a working signal.

[0017] As preferred, a protection resistor R6 is connected between the base B and the output end of the triode on-off control circuit, so as to avoid that the three-terminal voltage regulator U is directly connected to the two ends of the protection capacitor C.

[0018] A battery module comprises the battery protection circuit of the golf cart, and further comprises a vehicle motor system with two ends connected to a battery total positive interface P+ and a battery total negative interface P-.

[0019] Compared with the prior art, the utility model has the advantages of:

[0020] Once the battery is fully charged, the charging switch is turned off, and the excess feedback energy is used to charge several series-connected protection capacitors C to prevent damage to the vehicle's motor system.

[0021] When the voltage across the protective capacitor C is higher than the set value, the control circuit connects the balancing circuit, so that the dissipating resistor R2 is connected to the two ends of the protective capacitor C, thus dissipating the excess electrical energy and preventing damage to the protective capacitor C.

[0022] When the battery is not fully charged and the charging switch is turned on, the protection capacitor C will discharge, automatically charging the battery, protecting the vehicle's motor system while saving energy. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the overall circuit of Embodiment 1 of this utility model;

[0024] Figure 2 This is a schematic diagram of the sub-circuit of Embodiment 1 of this utility model that is directly connected to the main positive interface P+ of the battery;

[0025] Figure 3 This is a schematic diagram of the overall circuit system connection of Embodiment 2 of this utility model. Detailed Implementation

[0026] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of this utility model.

[0027] Example 1, as Figure 1 and Figure 2 As shown, a battery protection circuit for a golf cart is provided. The two ends of the battery protection circuit are connected to the battery's positive terminal P+ and the battery's negative terminal P-, respectively. The battery protection circuit includes several sub-circuits connected in series; in this embodiment, there are 24 sub-circuits. Each sub-circuit includes:

[0028] The protection capacitor C is connected in series with the protection capacitors of different sub-circuits. The protection capacitor C of this utility model is a farad capacitor with a specification of 30F / 2.7V.

[0029] A balancing resistor R1 is connected in parallel across the protection capacitor C. The balancing resistor R1 ensures that the voltage across each protection capacitor C is balanced by blocking the voltage drop across it.

[0030] Balanced circuit, including:

[0031] The power consumption resistor R2 includes several resistors connected in parallel. In this embodiment, the power consumption resistor R2 includes R21, R22, R23 and R24, and also includes a light-emitting diode (LED) as a working signal.

[0032] The control circuit has a switching element connected in series with the power consumption resistor R2 and then connected in parallel across the protection capacitor C. The control circuit is coupled to the protection capacitor C to collect the voltage across the protection capacitor C and controls the switching element to turn on or off based on whether the voltage is higher than a set value. The set value is set based on the rated capacitance of the protection capacitor C.

[0033] The control circuit includes a transistor Q as a switching element and a transistor on / off control circuit. The emitter E of transistor Q is connected to the positive terminal of the protection capacitor C, the collector L is connected to the dissipation resistor R2, and the base B is connected to the output terminal of the transistor on / off control circuit. The sampling terminal of the transistor on / off control circuit is connected to both ends of the protection capacitor C and controls the on / off state of transistor Q based on whether the voltage of the protection capacitor C is higher than the set value.

[0034] The transistor on / off control circuit includes a voltage regulator circuit and a voltage divider circuit connected in parallel. The voltage regulator circuit includes a voltage regulator resistor R3 and a three-terminal regulator U. The anode 2 of the three-terminal regulator U is connected to the positive terminal of the protection capacitor C through the voltage regulator resistor R3. The base B of the transistor Q is connected to the anode 2 of the three-terminal regulator U, and the cathode 3 of the three-terminal regulator U is connected to the negative terminal of the protection capacitor C. The sampling of the voltage divider circuit is coupled to the protection capacitor C, and the output terminal is connected to the reference terminal 1 of the three-terminal regulator U. The voltage divider circuit controls the on / off state of the three-terminal regulator U according to whether the voltage is higher than the set value.

[0035] The voltage divider circuit includes voltage divider resistors R4 and R5 connected in series. The output terminal of the voltage divider circuit is located between voltage divider resistors R4 and R5. The voltage or current output of the voltage divider circuit is adjusted using voltage divider resistors R4 and R5 to match the model of reference terminal 1 of the three-terminal regulator U. In this embodiment, the model of the three-terminal regulator U is TL432, therefore the voltage setting value of the output terminal of the voltage divider circuit is set to 2.5V.

[0036] A protective resistor R6 is connected between the base B and the output terminal of the transistor on / off control circuit to prevent the three-terminal regulator U from being directly connected to the two ends of the protective capacitor C.

[0037] The working principle of this embodiment is as follows:

[0038] When the battery is not fully charged, the charging switch is on, allowing excess feedback energy to be used to charge the battery. At this time, the protection capacitor C is not charged because the polarities are opposite. Therefore, the voltage across the protection capacitor C is lower than the set value, and the voltage in the voltage divider circuit is also lower than the set value of 2.5V. Anode 2 and cathode 3 remain disconnected, that is, the voltage regulator circuit is disconnected, so there is no current signal on the base B. The transistor Q remains disconnected, and the power consumption resistor R2 does not consume power.

[0039] When the battery is fully charged, the charging switch is turned off. The excess feedback energy is used to charge the 24 series-connected protection capacitors C. When the voltage across the protection capacitor C is higher than the set value, the voltage at the output of the voltage divider circuit is higher than the set value of 2.5V, thereby outputting current to the reference terminal 1 of the three-terminal regulator U to connect the anode 2 and the cathode 3. The voltage regulator circuit is connected, thereby transmitting a current signal to the base B, causing the transistor Q to conduct. The resistor R2 is connected to the two ends of the protection capacitor C, consuming the excess electrical energy and preventing damage to the protection capacitor C.

[0040] When the battery is depleted, turning the charging switch back on will discharge the protection capacitor C, automatically charging the battery. This causes the voltage across the protection capacitor C to drop below a set value. The voltage in the voltage divider circuit is below the set value of 2.5V, so anode 2 and cathode 3 remain disconnected, meaning the voltage regulator circuit is disconnected. This results in no current signal on the base B, and transistor Q remains disconnected. The power consumption resistor R2 does not consume power, reducing energy loss and protecting the vehicle's motor system while saving energy.

[0041] Example 2: A battery module, such as Figure 3 As shown, the battery protection circuit of the golf cart mentioned above is included, as well as the vehicle motor system with its two ends connected to the battery positive interface P+ and the battery negative interface P- respectively.

[0042] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the specific details of the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

Claims

1. A battery protection circuit for a golf cart, characterized in that, The battery protection circuit is connected to the battery's positive terminal P+ and negative terminal P- at its two ends, respectively. The battery protection circuit includes several sub-circuits connected in series, each sub-circuit comprising: The protection capacitors C of different sub-circuits are connected in series. A balancing resistor R1 is connected in parallel across the protective capacitor C. The balancing circuit includes a power consumption resistor R2 and a control circuit. The switching element of the control circuit is connected in series with the power consumption resistor R2 and then in parallel across the protection capacitor C. The control circuit is coupled to the protection capacitor C to collect the voltage across the protection capacitor C and control the switching element to turn on or off based on whether the voltage is higher than a set value.

2. The battery protection circuit for a golf cart according to claim 1, characterized in that, The control circuit includes a transistor Q as a switching element and a transistor on / off control circuit. The emitter E of the transistor Q is connected to the positive terminal of the protection capacitor C, the collector L is connected to the dissipation resistor R2, and the base B is connected to the output terminal of the transistor on / off control circuit. The sampling terminal of the transistor on / off control circuit is connected to both ends of the protection capacitor C and controls the on / off state of the transistor Q based on whether the voltage of the protection capacitor C is higher than a set value.

3. The battery protection circuit for a golf cart according to claim 2, characterized in that, The transistor on / off control circuit includes a voltage regulator circuit and a voltage divider circuit connected in parallel. The voltage regulator circuit includes a voltage regulator resistor R3 and a three-terminal regulator U. The anode 2 of the three-terminal regulator U is connected to the positive terminal of the protection capacitor C through the voltage regulator resistor R3. The base B of the transistor Q is connected to the anode 2 of the three-terminal regulator U. The cathode 3 of the three-terminal regulator U is connected to the negative terminal of the protection capacitor C. The sampling terminal of the voltage divider circuit is coupled to the protection capacitor C, and the output terminal is connected to the reference terminal 1 of the three-terminal regulator U. The voltage divider circuit controls the on / off state of the three-terminal regulator U based on whether the voltage of the protection capacitor C is higher than a set value.

4. The battery protection circuit for a golf cart according to claim 3, characterized in that, The voltage divider circuit includes voltage divider resistors R4 and R5 connected in series, and the output terminal of the voltage divider circuit is located between voltage divider resistors R4 and R5.

5. The battery protection circuit for a golf cart according to any one of claims 1-4, characterized in that, The power consumption resistor R2 comprises several resistors connected in parallel.

6. The battery protection circuit for a golf cart according to any one of claims 1-4, characterized in that, The power consumption resistor R2 also includes a light-emitting diode (LED).

7. The battery protection circuit for a golf cart according to any one of claims 2-4, characterized in that, A protective resistor R6 is connected between the base B and the output terminal of the transistor on / off control circuit.

8. A battery module, characterized in that, The battery protection circuit of the golf cart as described in any one of claims 1-7 further includes a vehicle motor system with its two ends respectively connected to the battery positive interface P+ and the battery negative interface P-.

Images