CN-117277458-B - Automatic power supply control circuit and method based on vehicle-mounted 24V system

CN117277458BCN 117277458 BCN117277458 BCN 117277458BCN-117277458-B

Abstract

The invention discloses a power supply automatic control circuit based on a vehicle-mounted 24V system, which comprises an ignition signal circuit, an enabling control circuit and a direct current voltage reduction circuit, wherein the power input end of the ignition signal circuit is electrically connected with the positive electrode of a vehicle-mounted 24V power supply, the level signal output end of the ignition signal circuit is electrically connected with the second input end of the enabling control circuit, the first input end of the enabling control circuit is electrically connected with the positive electrode of the vehicle-mounted 24V power supply, the input end of the direct current voltage reduction circuit is electrically connected with the positive electrode of the vehicle-mounted 24V power supply, the enabling end of the direct current voltage reduction circuit is electrically connected with the output end of the enabling control circuit, and the output end of the direct current voltage reduction circuit is electrically connected with a load circuit.

Inventors

WANG KANG
HE XIANGYU
ZHENG PENGXIANG

Assignees

深圳联友科技有限公司
联友智连科技有限公司

Dates

Publication Date: 20260505
Application Date: 20220613

Claims (8)

1. The utility model provides a power supply automatic control circuit based on-vehicle 24V system for according to on-vehicle 24V power state and car ignition state automatic control load circuit's power supply, its characterized in that: The automatic power supply control circuit comprises an ignition signal circuit, an enabling control circuit and a direct current voltage reduction circuit, wherein the power input end of the ignition signal circuit is electrically connected with the positive electrode of the vehicle-mounted 24V power supply, the level signal output end of the ignition signal circuit is electrically connected with the second input end of the enabling control circuit, the first input end of the enabling control circuit is electrically connected with the positive electrode of the vehicle-mounted 24V power supply, the input end of the direct current voltage reduction circuit is electrically connected with the positive electrode of the vehicle-mounted 24V power supply, the enabling end of the direct current voltage reduction circuit is electrically connected with the output end of the enabling control circuit, and the output end of the direct current voltage reduction circuit is electrically connected with the load circuit; The enabling control circuit outputs enabling control voltage according to the voltage values of the first input end and the second input end, and the direct current voltage reduction circuit controls the connection and disconnection of the output end and the input end according to the enabling control voltage value of the enabling end; the enabling control circuit comprises a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, a grounding end, an NPN triode, a PNP triode and a voltage stabilizing diode, wherein the cathode of the voltage stabilizing diode is used as a first input end of the enabling control circuit to be electrically connected with the positive electrode of the vehicle-mounted 24V power supply, the anode of the voltage stabilizing diode is sequentially connected with the first resistor, the second resistor, the third resistor and the grounding end in series, the anode of the voltage stabilizing diode is sequentially connected with the fourth resistor and the fifth resistor in series, the emitter of the PNP triode is electrically connected with the anode of the voltage stabilizing diode, the collector of the PNP triode is electrically connected with the first end of the second resistor, the second end of the second resistor is used as an output end of the enabling control circuit to be electrically connected with the enabling end of the direct-current step-down circuit, the anode of the PNP triode is electrically connected with the first end of the fifth resistor, the anode of the second resistor is electrically connected with the third resistor, the base of the second resistor is electrically connected with the third resistor, the third resistor is electrically connected with the collector of the second resistor, the third resistor is electrically connected with the first end of the second resistor, the third resistor is electrically connected with the third resistor, and the third resistor is electrically connected with the third resistor.
2. The on-vehicle 24V system-based power supply automatic control circuit according to claim 1, wherein: The direct-current voltage reduction circuit comprises a direct-current conversion direct-current voltage reduction chip, wherein the input end of the direct-current conversion direct-current voltage reduction chip is electrically connected with the positive electrode of the vehicle-mounted 24V power supply, the output end of the direct-current conversion direct-current voltage reduction chip is electrically connected with the load circuit to supply power for the load circuit, the enabling end of the direct-current conversion direct-current voltage reduction chip is electrically connected with the output end of the enabling control circuit, and the output voltage of the output end of the direct-current conversion direct-current voltage reduction chip is 5V.
3. The on-vehicle 24V system-based power supply automatic control circuit according to claim 2, wherein: The first resistor has a resistance value of 1.07MΩ, the second resistor has a resistance value of 220KΩ, the third resistor and the fifth resistor have a resistance value of 100KΩ, the fourth resistor has a resistance value of 499KΩ, the sixth resistor has a resistance value of 150KΩ, the seventh resistor has a resistance value of 10KΩ, and the zener diode has a voltage drop of 5.1V.
4. An automatic power supply control circuit based on a vehicle-mounted 24V system according to one of claims 1-3, characterized in that: The vehicle-mounted 24V power supply comprises two sections of 12V storage batteries, and the two sections of 12V storage batteries are connected in series to supply power to the outside.
5. A power supply automatic control method based on a vehicle-mounted 24V system for automatically controlling power supply of a load circuit according to a vehicle-mounted 24V power supply state and a vehicle ignition state, the method being performed by the power supply automatic control circuit based on a vehicle-mounted 24V system as set forth in claim 1, and comprising Step 100, detecting a vehicle-mounted 24V power supply voltage value and an automobile ignition signal level; step 200, inputting a detection value and outputting an enabling voltage signal associated with the selection calculation of the detection value; Step 300, judging whether the voltage value of the enabling voltage signal exceeds the critical voltage value so as to control the power-on and power-off of the load circuit; The step S200 comprises the steps of inputting a vehicle-mounted 24V power supply voltage value into a first input end of an enabling control circuit, inputting a vehicle ignition signal level value into a second input end of the enabling control circuit, and outputting an enabling voltage signal according to a formula Ven= (VCC-VD 1) R3/(R1+R2+R3) when the vehicle ignition signal level is low level; When the level of the automobile ignition signal is high, an enabling voltage signal is output according to a formula ven= (VCC-VD 1) ×r3/(r2+r3), wherein in the formula, ven is the voltage value of the enabling voltage signal, VCC is the voltage value of the on-board 24V power supply, VD1 is the voltage drop value of the zener diode, R1 is the first resistance value, R2 is the second resistance value, and R3 is the third resistance value.
6. The automatic power supply control method based on the vehicle-mounted 24V system according to claim 5, wherein: The step S300 comprises the steps of detecting the voltage value of the enabling voltage signal, comparing the voltage value of the enabling voltage signal with the critical voltage value, conducting a power-on line between the vehicle-mounted 24V power supply and the load circuit when the voltage value of the enabling voltage signal is higher than the critical voltage value, and disconnecting the power-on line between the vehicle-mounted 24V power supply and the load circuit when the voltage value of the enabling voltage signal is lower than the critical voltage value.
7. The automatic power supply control method based on the vehicle-mounted 24V system according to claim 5, wherein: the voltage drop value of the zener diode in the step S200 is 5.1V, the error±0.3, the resistance value of the first resistor is 1.07mΩ, the error±1%, the resistance value of the second resistor is 220kΩ, the error±1%, the resistance value of the third resistor is 100kΩ, and the error±1%.
8. The automatic power supply control method based on the vehicle-mounted 24V system according to claim 6, wherein: The threshold voltage value in the step S300 is 1.2V.

Description

Automatic power supply control circuit and method based on vehicle-mounted 24V system Technical Field The invention relates to the technical field of automobile power supplies, in particular to a power supply automatic control circuit and method based on a vehicle-mounted 24V system. Background With the progress of the automobile industry, large-sized vehicles with higher compression ratio and larger discharge capacity appear on the market, because the large-sized vehicles have high compression ratio and large friction coefficients of all parts, starting force can be blocked, and therefore, a high-voltage and high-current starter is required for starting, the traditional 12V power supply system is not satisfied, and a higher 24V power supply system is required. The 24V power supply adopts two 12V storage batteries connected in series, the corresponding highest voltage can reach 32V, and the lowest possible power consumption can reach below 9V. Because the battery voltage range is wider, and the automobile has two states of ignition and flameout, when the load circuit is powered by the storage battery, the switch state is required to be switched according to the instant storage battery power supply voltage value and the ignition state of the automobile. If the switch switching state cannot be automatically controlled according to the instant state, the voltage of the load circuit is abnormal, and when the voltage is severe, the electric leakage of the storage battery of the automobile is caused. At this time, it is considered that a low-cost automatic power supply control circuit is required to ensure that the automobile storage battery is not deficient, and at the same time, the load circuit can be ensured to operate normally. Disclosure of Invention The invention mainly aims to provide a low-cost automatic power supply control circuit and method based on a vehicle-mounted 24V system, aiming at the defect that in the prior art, the power-on and power-off state cannot be automatically controlled according to the instant state, so that the voltage of a load circuit is abnormal, and the electric leakage of an automobile storage battery is caused when the voltage is serious. In order to achieve the above purpose, the invention provides a power supply automatic control circuit based on a vehicle-mounted 24V system, which is used for automatically controlling the power supply of a load circuit according to the vehicle-mounted 24V power supply state and the vehicle ignition state, an ignition signal circuit, an enabling control circuit and a direct current voltage reduction circuit, wherein the power supply input end of the ignition signal circuit is electrically connected with the positive electrode of the vehicle-mounted 24V power supply, the level signal output end of the ignition signal circuit is electrically connected with the second input end of the enabling control circuit, the first input end of the enabling control circuit is electrically connected with the positive electrode of the vehicle-mounted 24V power supply, the input end of the direct current voltage reduction circuit is electrically connected with the positive electrode of the vehicle-mounted 24V power supply, and the enabling end of the direct current voltage reduction circuit is electrically connected with the output end of the enabling control circuit; the enabling control circuit outputs enabling control voltage according to the voltage values of the first input end and the second input end, and the direct current voltage reduction circuit controls the connection and disconnection of the output end and the input end according to the enabling control voltage value of the enabling end. Preferably, the enabling control circuit includes a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, a ground terminal, an NPN triode, a PNP triode and a zener diode, wherein a cathode of the zener diode is electrically connected with an anode of the vehicle-mounted 24V power supply as a first input terminal of the enabling control circuit, an anode of the zener diode is sequentially connected in series with the first resistor, the second resistor, the third resistor and the ground terminal, an anode of the zener diode is sequentially connected in series with the fourth resistor and the fifth resistor, an emitter of the PNP triode is electrically connected with an anode of the zener diode, a collector of the PNP triode is electrically connected with a first terminal of the second resistor, an output terminal of the second resistor is electrically connected with an enabling terminal of the vehicle-mounted 24V power supply as an output terminal of the enabling control circuit, an anode of the PNP triode is electrically connected with a fifth terminal of the fifth resistor, a base of the PNP triode is electrically connected with a base of the fifth resistor is electrically connected wit