Auxiliary power supply of electric automobile

Abstract

The utility model relates to the technical field of auxiliary power supply circuits, and discloses an electric automobile auxiliary power supply with reliable and stable reference voltage, which comprises a switch module (130) used for receiving a first voltage signal, an overcurrent protection module (120) and an adjusting module (140), when a second voltage signal is greater than a reference signal value, the overcurrent protection module (120) pulls a level signal to a low level, and the adjusting module (140) adjusts the second voltage signal to a low level. Therefore, the switch module (130) is controlled to be switched off.

Description

TECHNICAL FIELD

[0001] The utility model relates to auxiliary power supply circuit technical field more specifically, relate to a kind of electric automobile auxiliary power supply. BACKGROUND

[0002] In automobile application, there is usually 12V or 15V stabilized DC voltage for other purposes, and auxiliary power supply and DC-DC power converter provide power support for the auxiliary system of vehicle, to ensure that the vehicle runs stably in power mode. At present, the low-voltage power signal of the main controller is an integral part of the interface input part and the output, and the power signal needs to be converted from 24V to 5V inside the controller. In this process, the supply voltage may not be consistent with the reference voltage of the main controller. When the load is overloaded or overcurrent, the circuit system cannot protect the load from overload or overcurrent in time. SUMMARY

[0003] The technical problem to be solved by the utility model is that the supply voltage is inconsistent with the reference voltage of the main controller, which leads to the defect that the load cannot be protected from overcurrent in time when the load is in an overcurrent state. The utility model provides an electric automobile auxiliary power supply with reliable and stable reference voltage.

[0004] The utility model adopts the technical scheme to solve its technical problem: a kind of electric automobile auxiliary power supply is constructed, with:

[0005] Switching module, its first end is connected with the output end of the first output branch of auxiliary power supply, for receiving first voltage signal,

[0006] The second end of the switching module is connected with the output end of the second output branch of the auxiliary power supply, for receiving level signal;

[0007] Overcurrent protection module, with reference signal value, its first end is connected with the output end of the first output branch,

[0008] The second end of the overcurrent protection module is also connected with the output end of the second output branch and the second end of the switching module,

[0009] The second end of the switching module is connected,

[0010] The third end of the overcurrent protection module is connected with one end of the output loop of the first output branch, for receiving second voltage signal output by the first output branch;

[0011] Adjusting module, its input end is connected with the second end of the switching module, for receiving the voltage signal;

[0012] When the second voltage signal is greater than the reference signal value, the overcurrent protection module pulls the level signal to a low level to control the switch module to turn off.

[0013] In some embodiments, the switching module includes a first transistor, a second transistor, and a third transistor.

[0014] The collectors of the first transistor, the second transistor, and the third transistor are connected to the output terminal of the auxiliary power supply.

[0015] The emitter of the first transistor is coupled to the input terminal of the adjustment module.

[0016] The base of the first transistor is connected to the emitter of the second transistor.

[0017] The emitter of the third transistor is connected to the base of the second transistor.

[0018] The base of the third transistor is connected to the output terminal of the second output branch and the first terminal of the overcurrent protection module.

[0019] In some embodiments, the overcurrent protection module includes a sampling resistor, a second adjustable resistor, and a fourth transistor.

[0020] One end of the sampling resistor is connected to one end of the output circuit of the first output branch, and is used to receive the second voltage signal.

[0021] One end and the adjustment terminal of the second adjustable resistor are connected to the other end of the sampling resistor.

[0022] The base of the fourth transistor is connected to the output terminal of the first output branch.

[0023] The collector of the fourth transistor is connected to the base of the third transistor.

[0024] The emitter of the fourth transistor is connected to the other end of the second adjustable resistor.

[0025] In some embodiments, the first transistor, the second transistor, the third transistor, and the fourth transistor are selected as NPN transistors.

[0026] In some embodiments, the adjustment module includes at least a first adjustable resistor.

[0027] One end of the first adjustable resistor is connected to the emitter of the first transistor via a sixth resistor.

[0028] The other end of the first adjustable resistor is connected to one end of the sampling resistor through an eighth resistor.

[0029] In some embodiments, the adjustment module further includes a fifth transistor and a sixth transistor.

[0030] The base of the fifth transistor is connected to the adjustment terminal of the first adjustable resistor.

[0031] The collector of the fifth transistor is connected to the output terminal of the second output branch through the seventh resistor.

[0032] The base of the sixth transistor is connected to the emitter of the first transistor through the ninth resistor.

[0033] The collector of the sixth transistor is connected to the emitter of the first transistor.

[0034] The emitter of the fifth transistor and the emitter of the sixth transistor are connected to one end of the sampling resistor through the tenth resistor.

[0035] In some embodiments, the fifth transistor and the sixth transistor are selected as NPN transistors.

[0036] In some implementations, the input terminal of the first output branch is connected to one end of the secondary winding of the transformer.

[0037] The output terminal of the first output branch is connected to the collector of the first transistor.

[0038] In some embodiments, a voltage regulator module is also included, one end of which is connected to the output terminal of the first output branch.

[0039] One end of the voltage regulator module is connected to the third end of the overcurrent protection module.

[0040] The electric vehicle auxiliary power supply described in this utility model includes a switching module for receiving a first voltage signal, an overcurrent protection module, and an adjustment module. When the second voltage signal is greater than a reference signal value, the overcurrent protection module pulls the level signal to a low level to control the switching module to turn off. Compared with the prior art, the overcurrent protection module obtains the voltage signal of the output circuit and compares it with a preset voltage reference value. When the voltage signal is greater than the voltage reference value, the overcurrent protection module can pull the control signal of the switching module low, causing it to switch from an on to an off state. The adjustment module can also adjust the voltage reference value range according to load requirements, thereby improving the practicality of the circuit. This effectively solves the problem that the existing power supply voltage is inconsistent with the reference voltage of the main controller, and the circuit system cannot provide timely overload or overcurrent protection when the load is overloaded or overcurrent. Attached Figure Description

[0041] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings:

[0042] Figure 1 This is a partial schematic diagram of an embodiment of the auxiliary power supply for electric vehicles provided by this utility model. Detailed Implementation

[0043] To provide a clearer understanding of the technical features, objectives, and effects of this utility model, the specific embodiments of this utility model will now be described in detail with reference to the accompanying drawings.

[0044] like Figure 1 As shown, in the first embodiment of the electric vehicle auxiliary power supply of this utility model, the electric vehicle auxiliary power supply 10 includes a first output branch 110, an overcurrent protection module 120, a switching module 130, and an adjustment module 140.

[0045] The first output branch 110 is used to rectify and filter the input voltage signal and output a DC voltage.

[0046] The overcurrent protection module 120 is equipped with a voltage preset value, which is used to acquire the electrical signal (voltage or current signal) at the load end, compare the acquired electrical signal (voltage or current signal) with the voltage preset value, and then output a control level signal according to the comparison result.

[0047] The switch module 130 is used to control the on / off state of the first output branch;

[0048] The adjustment module 140 is used to adjust the voltage preset value range of the overcurrent protection module 120 to adapt to the load requirements;

[0049] Specifically, the first terminal of the switching module 130 (corresponding to the collector of the first transistor VT101) is connected to the output terminal of the first output branch 110 of the auxiliary power supply, for receiving a first voltage signal (such as 22V) and outputting the first voltage signal to the switching module 130.

[0050] Furthermore, the second terminal of the switching module 130 (corresponding to the base of the third transistor VT103) is connected to the output terminal of the second output branch of the auxiliary power supply, for receiving the level signal and outputting the level signal to the overcurrent protection module 120;

[0051] The second output branch is formed by connecting the fifth diode D105, the sixth diode D106, and the twelfth resistor R112 in series.

[0052] The overcurrent protection module 120 is equipped with a reference signal value (e.g., 5V).

[0053] The first terminal of the overcurrent protection module 120 (corresponding to the base of the fourth transistor VT104) is connected to the output terminal of the first output branch 110 through the first resistor R101, and is used to receive control signals. When the control signal is high, the overcurrent protection module 120 is turned on; when the control signal is low, the overcurrent protection module 120 is turned off.

[0054] The second terminal of the overcurrent protection module 120 (corresponding to the collector of the fourth transistor VT104) is connected to the output terminal of the second output branch through the seventh resistor R107.

[0055] The second terminal of the overcurrent protection module 120 (corresponding to the collector of the fourth transistor VT104) is connected to the third terminal of the switching module 130. When the overcurrent protection module 120 is turned on, the electrical signal at the second terminal of the switching module 130 can be pulled to a low level so that the controller can turn it off.

[0056] The third terminal of the overcurrent protection module 120 (corresponding to the emitter of the fourth transistor VT104) is connected to one end of the output circuit of the first output branch 110, and is used to receive the second voltage signal output by the first output branch 110, compare it with the preset voltage value, and then output a control level signal according to the comparison result.

[0057] Furthermore, the input terminal of the adjustment module 140 is connected to the second terminal of the switch module 130 for receiving voltage signals;

[0058] When the second voltage signal is greater than the reference signal value, the overcurrent protection module 120 pulls the level signal of the second terminal of the switch module 130 to a low level to control the switch module 130 to turn off, so as to ensure that the output circuit of the switch module 130 can be turned off in time when the load is in an overcurrent state.

[0059] Using this technical solution, the overcurrent protection module 120 obtains the voltage signal of the output circuit and compares it with the preset voltage reference value. When the voltage signal is greater than the voltage reference value, the overcurrent protection module 120 can pull down the control signal of the switching module, causing it to switch from the on state to the off state. The adjustment module 140 can also adjust the voltage reference value range according to the load requirements, thereby improving the practicality of the circuit. It can effectively solve the problem that the existing power supply voltage is inconsistent with the reference voltage of the main controller, and the circuit system cannot provide overload or overcurrent protection to the load in time when the load is overloaded or overcurrent.

[0060] In some implementations, such as Figure 1 As shown, in order to improve the control effect of the output circuit on / off, a first transistor VT101, a second transistor VT102 and a third transistor VT103 can be set in the switching module 130. Among them, the first transistor is selected as an NPN type transistor, which all have the function of switching.

[0061] Specifically, the collectors of the first transistor VT101, the second transistor VT102, and the third transistor VT103 are connected to the output terminal of the first output branch 110 (which belongs to the auxiliary power supply) to receive the first voltage signal.

[0062] The emitter of the first transistor VT101 is connected to one input terminal of the adjustment module 140.

[0063] The base of the first transistor VT101 is connected to the emitter of the second transistor VT102.

[0064] The emitter of the third transistor VT103 is connected to the base of the second transistor VT102.

[0065] The base of the third transistor VT103 is connected to the output terminal of the second output branch and the first terminal of the overcurrent protection module 120 through the sixth resistor R106 for level signal. When the input level signal is high, the third transistor VT103, the second transistor VT102 and the first transistor VT101 are controlled to conduct to output the first voltage signal.

[0066] In some implementations, such as Figure 1 As shown, to improve the timeliness of overcurrent protection, a sampling resistor R111, a second adjustable resistor RP2, and a fourth transistor VT104 can be set in the overcurrent protection module 120. The sampling resistor R111 is selected with a resistance of 100Ω and is used to acquire the voltage / voltage signal at the load terminal.

[0067] The second adjustable resistor RP2 is used to adjust the resistance of the detection circuit.

[0068] The fourth transistor, VT104, functions as a switch.

[0069] Specifically, one end of the sampling resistor R111 is connected to one end of the output circuit (or load end) of the first output branch 110 to receive the second voltage signal.

[0070] One end and the adjustment end of the second adjustable resistor RP2 are connected to the other end of the sampling resistor R111.

[0071] The base of the fourth transistor VT104 is connected to the output terminal of the first output branch 110 through the third resistor R103, and is used to receive level signals.

[0072] The collector of the fourth transistor VT104 is connected to the base of the third transistor VT103.

[0073] The emitter of the fourth transistor VT104 is connected to the other end of the second adjustable resistor RP2.

[0074] When the first voltage signal obtained by the sampling resistor R111 is greater than the reference signal value, and the base voltage of the fourth transistor VT104 is at a high level, it is controlled to conduct. The level signal passes through its collector-emitter junction, causing the level signal at the base of the third transistor VT103 to be pulled to a low level and controlled to turn off.

[0075] In some implementations, such as Figure 1 As shown, to adjust the range of the reference signal value, a first adjustable resistor RP1 can be set in the adjustment module 140.

[0076] Specifically, one end of the first adjustable resistor RP1 is connected to the emitter of the first transistor VT101 through the sixth resistor R106.

[0077] The other end of the first adjustable resistor RP1 is connected to one end of the sampling resistor R111 through the eighth resistor R108.

[0078] Furthermore, the adjustment module 140 also includes a fifth transistor VT105 and a sixth transistor VT106. The transistors are NPN type transistors and all have the function of switching.

[0079] Specifically, the base of the fifth transistor VT105 is connected to the adjustment terminal of the first adjustable resistor RP1.

[0080] The collector of the fifth transistor VT105 is connected to the output terminal of the second output branch through the seventh resistor R107.

[0081] The base of the sixth transistor VT106 is connected to the emitter of the first transistor VT101 through the ninth resistor R109.

[0082] The collector of the sixth transistor VT106 is connected to the emitter of the first transistor VT101.

[0083] The emitter of the fifth transistor VT105 and the emitter of the sixth transistor VT106 are connected to one end of the sampling resistor R111 through the tenth resistor R110. The potential state of the base of the fifth transistor VT105 is controlled by the resistance value of the first adjustable resistor RP1. When the fifth transistor VT105 is turned on, the level signal is transmitted to the common terminal through the collector and emitter of the fifth transistor VT105.

[0084] In some implementations, in order to ensure the stability of the output first voltage signal, the input terminal of the first output branch 110 can be connected to one end of the secondary winding of the transformer TR1 to receive the level signal coupled out by the transformer TR1.

[0085] The output terminal of the first output branch 110 is connected to the collector of the first transistor VT101, and the first voltage signal is output to the subsequent circuit (or load) through the first transistor VT101.

[0086] In some implementations, such as Figure 1 As shown, it also includes a voltage regulator module, wherein one end of the voltage regulator module is connected to the output terminal of the first output branch 110.

[0087] One end of the voltage regulator module is connected to the third end of the overcurrent protection module 120 (corresponding to the other end of the sampling resistor R111).

[0088] The voltage regulator module includes a first Zener diode VS101, whose cathode is connected to the base of a fourth transistor VT10 through a third resistor R103, and whose anode is connected to the other end of a sampling resistor R111.

[0089] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

Claims

1. An auxiliary power supply for an electric vehicle, characterized in that, have: The switching module has its first terminal connected to the output terminal of the first output branch of the auxiliary power supply, and is used to receive the first voltage signal. The second terminal of the switching module is connected to the output terminal of the second output branch of the auxiliary power supply, and is used to receive level signals; The overcurrent protection module has a reference signal value, and its first terminal is connected to the output terminal of the first output branch. The second terminal of the overcurrent protection module is also connected to the output terminal of the second output branch and the second terminal of the switch module. The third terminal of the overcurrent protection module is connected to one end of the output circuit of the first output branch, and is used to receive the second voltage signal output by the first output branch; An adjustment module, the input terminal of which is connected to the second terminal of the switch module, is used to receive the voltage signal; When the second voltage signal is greater than the reference signal value, the overcurrent protection module pulls the level signal to a low level to control the switch module to turn off.

2. The electric vehicle auxiliary power supply according to claim 1, characterized in that, The switching module includes a first transistor, a second transistor, and a third transistor. The collectors of the first transistor, the second transistor, and the third transistor are connected to the output terminal of the auxiliary power supply. The emitter of the first transistor is coupled to the input terminal of the adjustment module. The base of the first transistor is connected to the emitter of the second transistor. The emitter of the third transistor is connected to the base of the second transistor. The base of the third transistor is connected to the output terminal of the second output branch and the first terminal of the overcurrent protection module.

3. The electric vehicle auxiliary power supply according to claim 2, characterized in that, The overcurrent protection module includes a sampling resistor, a second adjustable resistor, and a fourth transistor. One end of the sampling resistor is connected to one end of the output circuit of the first output branch, and is used to receive the second voltage signal. One end and the adjustment terminal of the second adjustable resistor are connected to the other end of the sampling resistor. The base of the fourth transistor is connected to the output terminal of the first output branch. The collector of the fourth transistor is connected to the base of the third transistor. The emitter of the fourth transistor is connected to the other end of the second adjustable resistor.

4. The electric vehicle auxiliary power supply according to claim 3, characterized in that, The first transistor, the second transistor, the third transistor, and the fourth transistor are selected as NPN transistors.

5. The electric vehicle auxiliary power supply according to claim 3, characterized in that, The adjustment module includes at least a first adjustable resistor. One end of the first adjustable resistor is connected to the emitter of the first transistor via a sixth resistor. The other end of the first adjustable resistor is connected to one end of the sampling resistor through an eighth resistor.

6. The electric vehicle auxiliary power supply according to claim 5, characterized in that, The adjustment module also includes a fifth transistor and a sixth transistor. The base of the fifth transistor is connected to the adjustment terminal of the first adjustable resistor. The collector of the fifth transistor is connected to the output terminal of the second output branch through the seventh resistor. The base of the sixth transistor is connected to the emitter of the first transistor through the ninth resistor. The collector of the sixth transistor is connected to the emitter of the first transistor. The emitter of the fifth transistor and the emitter of the sixth transistor are connected to one end of the sampling resistor through the tenth resistor.

7. The electric vehicle auxiliary power supply according to claim 6, characterized in that, The fifth and sixth transistors are selected as NPN transistors.

8. The auxiliary power supply for electric vehicles according to claim 6, characterized in that, The input terminal of the first output branch is connected to one end of the secondary winding of the transformer. The output terminal of the first output branch is connected to the collector of the first transistor.

9. The auxiliary power supply for electric vehicles according to claim 8, characterized in that, It also includes a voltage regulator module, one end of which is connected to the output terminal of the first output branch. One end of the voltage regulator module is connected to the third end of the overcurrent protection module.

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