Armored vehicle power supply overvoltage protection circuit

Abstract

The utility model discloses an armored vehicle power supply overvoltage protection circuit which receives input voltage through a peak protection module, and the peak protection module carries out filtering processing on peak voltage and power supply burrs in the input voltage so as to realize peak protection. The reverse connection protection module is arranged between the peak protection module and the surge overvoltage protection module and is used for performing reverse connection protection on the power supply of the armored vehicle; a surge overvoltage protection module is arranged behind the reverse connection protection module, and a voltage stabilization unit is arranged in the surge overvoltage protection module to ensure that the voltage is constant during normal conduction; the control unit is used for adjusting the input voltage to ensure that the output voltage is constant so as to ensure the normal work of the circuit; and the delay starting unit has a delay starting function, and the circuit is protected from being damaged by peak surge voltage when the circuit is powered on for the first time through the delay starting function.

Description

Technical Field

[0001] The utility model relates to the technical field of overvoltage protection circuits, in particular to an armored vehicle power supply overvoltage protection circuit. Background Art

[0002] At present, the electrical equipment of armored vehicles often faces uncertain safety hazards such as reverse connection, spikes, surges, overvoltage, etc. from the power input end. Each power abnormality may cause permanent and irreversible damage to the power input circuit, thereby affecting the safety and reliability of the overall circuit.

[0003] Specifically, armored vehicle electrical equipment currently usually uses three types of components, namely varistors, diodes, and TVS transient suppression diodes, for spike, surge, and reverse connection protection. This type of circuit has an obvious disadvantage in actual use. When the power input has a long-term overvoltage and a high-amplitude surge voltage (the normal operating voltage of an armored vehicle is generally DC26V±4V, but when it starts, the power supply voltage will fluctuate within the range of 9-36V, and the surge voltage can be as high as 100V depending on the vehicle load), once the protection voltage of the TVS transient suppression diode is exceeded, the transient diode is very easy to break down and damage, causing a short circuit in the power input, thereby affecting the safety and reliability of the overall circuit, and using a dedicated protection module will greatly increase the circuit cost. Utility Model Content

[0004] In response to the problems raised by the above background technology, the purpose of the utility model is to provide an armored vehicle power supply overvoltage protection circuit, which adopts common electronic components such as varistors, triodes, field effect transistors, resistors, capacitors, etc. to achieve safe and reliable reverse connection protection and spike and surge overvoltage protection of armored vehicle power supply input. The circuit can freely and flexibly design the output voltage value so that it is not affected by fluctuations caused by changes in input voltage.

[0005] The utility model is realized by the following technical solutions:

[0006] An armored vehicle power supply overvoltage protection circuit, comprising:

[0007] A spike protection module, a reverse connection protection module and a surge overvoltage protection module connected in sequence;

[0008] Among them, the surge overvoltage protection module includes a voltage stabilization unit, a control unit and a delayed start unit;

[0009] The voltage stabilization unit is used to maintain voltage stability when the overvoltage protection circuit is turned on;

[0010] The control unit is used to ensure a constant input voltage by adjusting the input voltage;

[0011] The delayed start unit is used for delaying the start of the overvoltage protection circuit.

[0012] In the above technical solution, the normal working voltage of the armored vehicle is generally DC26V±4V. The power overvoltage protection circuit is connected to the armored vehicle, and the input voltage is received through the spike protection module. The spike protection module filters the spike voltage and power burrs in the input voltage to achieve spike protection. The reverse connection protection module is arranged between the spike protection module and the surge overvoltage protection module to perform reverse connection protection on the power supply of the armored vehicle.

[0013] A surge overvoltage protection module is arranged behind the reverse connection protection module. A voltage stabilization unit is arranged in the surge overvoltage protection module, which ensures that the voltage is constant during normal conduction; a control unit, which adjusts the input voltage to ensure that its output voltage is constant to ensure the normal operation of the circuit; a delayed start unit, which has a delayed start function, and the delayed start function protects the circuit from damage caused by the peak surge voltage when the power is first turned on.

[0014] In an optional embodiment, the voltage stabilization unit includes a voltage stabilizing diode D2, a resistor R3 and a MOS tube Q1;

[0015] The resistor R3 is connected in series with the voltage stabilizing diode D2 to form a voltage dividing resistor which is then connected to the MOS transistor Q1 .

[0016] In an optional embodiment, the control unit includes a transistor Q3, a transistor Q4, a voltage stabilizing diode D3, a resistor R5 and a resistor R6;

[0017] Among them, the base of the transistor Q3 is connected to the collector of the transistor Q4, the first end of the resistor R6 is connected to the emitter of the transistor Q3, the second end of the resistor R6 is connected to the cathode of the voltage stabilizing diode D3, and the base of the transistor Q4 is connected to the resistor R5.

[0018] In an optional embodiment, a resistor R4 is further provided between the base of the transistor Q3 and the collector of the transistor Q4.

[0019] In an optional embodiment, a resistor R7 is further provided between the resistor R5 and the anode of the voltage stabilizing diode D3.

[0020] In an optional embodiment, the surge overvoltage protection module also includes a resistor R1, a first end of the resistor R1 is connected to the middle node between the resistor R3 and the voltage zener diode D2, and a second end of the resistor R1 is connected to the middle node between the transistor Q3 and the MOS tube Q1.

[0021] In an optional embodiment, the delayed start unit includes a capacitor C2 and a capacitor C3, and the capacitor C2 and the capacitor C3 are both connected in parallel between the positive electrode and the negative electrode of the voltage stabilizing diode D3.

[0022] In an optional embodiment, the spike protection module includes a varistor RV1 and a capacitor C1, and the varistor RV1 is connected in parallel with the capacitor C1.

[0023] In an optional embodiment, the reverse connection protection module includes a MOS tube Q2, a voltage regulator diode D1, and a resistor R2;

[0024] The resistor R2 is connected to the anode of the Zener diode D1, the first port of the MOS transistor Q2 is connected to the middle node between the resistor R2 and the Zener diode D1, and the third port of the MOS transistor Q2 is connected to the cathode of the Zener diode D1.

[0025] In an optional embodiment, the model of the MOS tube Q2 is HSU70P06, and the model of the voltage regulator diode D1 is MMSZ5243B.

[0026] Compared with the prior art, the utility model has the following advantages and beneficial effects:

[0027] 1. The combined circuit constructed by discrete components such as varistors, ceramic capacitors, MOS tubes, triodes, and voltage-stabilizing diodes has the functions of spike, surge, reverse connection, and overvoltage protection;

[0028] 2. The cost of the combined circuit constructed by discrete components such as varistors, ceramic capacitors, MOS tubes, triodes, and voltage-stabilizing diodes is lower than that of dedicated modules;

[0029] 3. The output voltage amplitude is set by the voltage divider resistor so that it is not affected by power supply fluctuations;

[0030] 4. It has a delayed start function to protect the subsequent circuit from damage caused by the peak surge voltage when powered on for the first time. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The drawings described herein are used to provide a further understanding of the embodiments of the present utility model, constitute a part of this application, and do not constitute a limitation of the embodiments of the present utility model. In the drawings:

[0032] Figure 1 An armored vehicle power supply overvoltage protection circuit provided in Example 1 of the utility model;

[0033] Figure 2 The spike protection module provided in Example 1 of the utility model;

[0034] Figure 3 The reverse connection protection module provided in Example 1 of the utility model;

[0035] Figure 4 This is the surge overvoltage protection module provided in Example 1 of the utility model. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solutions and advantages of the utility model more clearly understood, the utility model is described in detail in an optional embodiment in combination with the embodiments and drawings below. The schematic implementation mode of the utility model and its description are only used to explain the utility model and are not intended to limit the utility model.

[0037] Example 1

[0038] This embodiment 1 provides an armored vehicle power supply overvoltage protection circuit, such as Figure 1 As shown, an armored vehicle overvoltage protection circuit includes:

[0039] A spike protection module, a reverse connection protection module and a surge overvoltage protection module connected in sequence;

[0040] Among them, the surge overvoltage protection module includes a voltage stabilization unit, a control unit and a delayed start unit;

[0041] The voltage stabilization unit is used to maintain voltage stability when the overvoltage protection circuit is turned on;

[0042] The control unit is used to ensure a constant input voltage by adjusting the input voltage;

[0043] The delayed start unit is used for delaying the start of the overvoltage protection circuit.

[0044] It should be noted that currently, the electrical equipment of armored vehicles often receives uncertain safety hazards such as reverse connection, spikes, surges, overvoltage, etc. from the power input terminal. Each power abnormality may cause permanent and irreversible damage to the power input circuit, thereby affecting the safety and reliability of the overall circuit. In view of the above situation, the utility model designs a power overvoltage protection circuit that can overcome the above shortcomings, which has reverse connection protection, spike absorption protection, surge suppression protection and overvoltage protection functions.

[0045] Specifically, the normal operating voltage of an armored vehicle is generally DC26V±4V. The power overvoltage protection circuit is connected to the armored vehicle, and the input voltage is received through the spike protection module. The spike protection module filters the spike voltage and power burrs in the input voltage to achieve spike protection. The reverse connection protection module is arranged between the spike protection module and the surge overvoltage protection module to perform reverse connection protection on the power supply of the armored vehicle.

[0046] A surge overvoltage protection module is arranged behind the reverse connection protection module. A voltage stabilization unit is arranged in the surge overvoltage protection module, which ensures that the voltage is constant during normal conduction; a control unit, which adjusts the input voltage to ensure that its output voltage is constant to ensure the normal operation of the circuit; a delayed start unit, which has a delayed start function, and the delayed start function protects the circuit from damage caused by the peak surge voltage when the power is first turned on.

[0047] In an optional embodiment, the voltage stabilization unit includes a voltage stabilizing diode D2, a resistor R3 and a MOS tube Q1;

[0048] The resistor R3 is connected in series with the voltage stabilizing diode D2 to form a voltage dividing resistor which is then connected to the MOS transistor Q1 .

[0049] Among them, Figure 4 As shown, the resistor R3 is connected to the positive electrode of the voltage-regulating diode D2 to form a voltage-dividing resistor, and the negative electrode of the voltage-regulating diode D2 in the voltage-dividing resistor is connected to the gate of the MOS transistor Q1 to ensure that the voltage between the gate and the source of the MOS transistor Q1 is constant when it is normally turned on.

[0050] In this embodiment, the resistance of the resistor R3 is 5.1 k ohms, the voltage stabilizing diode D2 is of model MMSZ5243B, and the MOS tube Q1 is of model HSU70P06.

[0051] In an optional embodiment, the control unit includes a transistor Q3, a transistor Q4, a voltage stabilizing diode D3, a resistor R5 and a resistor R6;

[0052] Among them, the base of the transistor Q3 is connected to the collector of the transistor Q4, the first end of the resistor R6 is connected to the emitter of the transistor Q3, the second end of the resistor R6 is connected to the cathode of the voltage stabilizing diode D3, and the base of the transistor Q4 is connected to the resistor R5.

[0053] In an optional embodiment, a resistor R4 is further provided between the base of the transistor Q3 and the collector of the transistor Q4.

[0054] In an optional embodiment, a resistor R7 is further provided between the resistor R5 and the anode of the voltage stabilizing diode D3.

[0055] Among them, Figure 4As shown, the working voltage 7.5V of the voltage zener diode plus the voltage difference 0.7V between the emitter and the base of the transistor Q4 when it is turned on constitutes the reference voltage 8.2V of the control unit. The control multiple of the control unit is determined by the resistor R5 and the resistor R7. In this embodiment, the resistance value of the resistor R5 is 32k ohms, and the resistance value of the resistor R7 is 10k ohms. Then the control multiple of the control unit is (R5+R7) / R7=4.2 times, and the protection voltage amplitude of VCC is 4.2*8.2=34.4V.

[0056] When the input voltage exceeds 34.4V, transistor Q4 is turned on, which in turn turns on transistor Q3 and turns off MOS tube Q1.

[0057] When the input voltage is lower than 34.4V, transistor Q4 is turned off, which in turn turns off transistor Q3 and turns on MOS tube Q1.

[0058] The control unit adjusts the input voltage through continuous switching actions to ensure that its output voltage is constant to protect the normal operation of the subsequent circuit.

[0059] In this embodiment, the model of the voltage stabilizing diode D3 is MMSZ5236B, the model of the transistor Q3 is MMBTA92, the model of the transistor Q4 is MMBT5551, and the resistance value of the resistor R4 is 10k ohms.

[0060] In an optional embodiment, the surge overvoltage protection module also includes a resistor R1, a first end of the resistor R1 is connected to the middle node between the resistor R3 and the voltage zener diode D2, and a second end of the resistor R1 is connected to the middle node between the transistor Q3 and the MOS tube Q1.

[0061] In an optional embodiment, the delayed start unit includes a capacitor C2 and a capacitor C3, and the capacitor C2 and the capacitor C3 are both connected in parallel between the positive electrode and the negative electrode of the voltage stabilizing diode D3.

[0062] Among them, the delayed start unit has a delayed start function. When the power is initially turned on, the voltage on the capacitor C2 and the capacitor C3 cannot change suddenly, so that the transistor Q4 is turned on for a certain period of time. Until its voltage value is equal to the working voltage of the voltage-stabilizing diode D3, the entire circuit will be turned on. The delayed start function protects the subsequent circuit from damage caused by the peak surge voltage when the power is first turned on.

[0063] It should be noted that the start-up delay time can be set by selecting the values ​​of capacitors C2 and C3.

[0064] It should be noted that if Figure 4As shown, the surge overvoltage protection module includes a MOS tube Q1, a triode Q3, a triode Q4, a zener diode D2, a zener diode D3, a resistor R1, a resistor R3, a resistor R4, a resistor R5, a resistor R6, a resistor R7, and a capacitor C2, a capacitor C3, and the above electrical components are all discrete components.

[0065] In an optional embodiment, the spike protection module includes a varistor RV1 and a capacitor C1, and the varistor RV1 is connected in parallel with the capacitor C1.

[0066] Among them, Figure 2 As shown, the varistor RV1 and the capacitor C1 are connected in parallel to the power input terminal, and the peak voltage and power burr of the input terminal are filtered through the varistor RV1 and the capacitor C1.

[0067] In this embodiment, the capacitor C1 is a ceramic capacitor, and the model of the varistor RV1 is RV_10D470.

[0068] In an optional embodiment, the reverse connection protection module includes a MOS tube Q2, a voltage regulator diode D1, and a resistor R2;

[0069] The resistor R2 is connected to the anode of the Zener diode D1, the first port of the MOS transistor Q2 is connected to the middle node between the resistor R2 and the Zener diode D1, and the third port of the MOS transistor Q2 is connected to the cathode of the Zener diode D1.

[0070] like Figure 3 As shown, a power reverse connection protection circuit is composed of a MOS tube Q2, a voltage zener diode D1, and a resistor R2. The voltage zener diode D1 and the resistor R1 form a voltage divider resistor connected to the gate of the MOS tube Q2 to ensure that the voltage between the gate and the source of the MOS tube is constant when the MOS tube is normally turned on.

[0071] In this embodiment, the model of the MOS tube Q2 is HSU70P06, and the model of the voltage regulator diode D1 is MMSZ5243B.

[0072] It should be noted that since the power supply overvoltage protection circuit provided by the utility model is composed of separate components such as varistors, ceramic capacitors, MOS tubes, triodes, and voltage-stabilizing diodes, the combined circuit is small in size, highly safe, and reliable, and can be flexibly transplanted to other products.

[0073] The specific implementation methods described above further illustrate the purpose, technical solutions and beneficial effects of the utility model in detail. It should be understood that the above description is only the specific implementation method of the utility model and is not used to limit the protection scope of the utility model. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the utility model should be included in the protection scope of the utility model.

Claims

1. An armored vehicle power supply overvoltage protection circuit, characterized in that: include: A spike protection module, a reverse connection protection module and a surge overvoltage protection module connected in sequence; Among them, the surge overvoltage protection module includes a voltage stabilization unit, a control unit and a delayed start unit; The voltage stabilization unit is used to maintain voltage stability when the overvoltage protection circuit is turned on; The control unit is used to ensure a constant input voltage by adjusting the input voltage; The delayed start unit is used for delaying the start of the overvoltage protection circuit.

2. The armored vehicle power supply overvoltage protection circuit according to claim 1, characterized in that: The voltage stabilization unit includes a voltage stabilizing diode D2, a resistor R3 and a MOS tube Q1; The resistor R3 is connected in series with the voltage stabilizing diode D2 to form a voltage dividing resistor which is then connected to the MOS transistor Q1 .

3. The armored vehicle power supply overvoltage protection circuit according to claim 2, characterized in that: The control unit includes a transistor Q3, a transistor Q4, a voltage stabilizing diode D3, a resistor R5 and a resistor R6; Among them, the base of the transistor Q3 is connected to the collector of the transistor Q4, the first end of the resistor R6 is connected to the emitter of the transistor Q3, the second end of the resistor R6 is connected to the cathode of the voltage stabilizing diode D3, and the base of the transistor Q4 is connected to the resistor R5.

4. The armored vehicle power supply overvoltage protection circuit according to claim 3, characterized in that: A resistor R4 is further provided between the base of the transistor Q3 and the collector of the transistor Q4.

5. The armored vehicle power supply overvoltage protection circuit according to claim 3, characterized in that: A resistor R7 is further provided between the resistor R5 and the anode of the voltage stabilizing diode D3.

6. The armored vehicle power supply overvoltage protection circuit according to claim 3, characterized in that: The surge overvoltage protection module further includes a resistor R1, a first end of the resistor R1 is connected to a middle node between the resistor R3 and the voltage stabilizing diode D2, and a second end of the resistor R1 is connected to a middle node between the transistor Q3 and the MOS transistor Q1.

7. The armored vehicle power supply overvoltage protection circuit according to claim 3, characterized in that: The delayed start unit includes a capacitor C2 and a capacitor C3, and the capacitor C2 and the capacitor C3 are both connected in parallel between the positive electrode and the negative electrode of the voltage stabilizing diode D3.

8. The armored vehicle power supply overvoltage protection circuit according to claim 1, characterized in that: The spike protection module includes a varistor RV1 and a capacitor C1, and the varistor RV1 is connected in parallel with the capacitor C1.

9. The armored vehicle power supply overvoltage protection circuit according to claim 1, characterized in that: The reverse connection protection module includes a MOS tube Q2, a voltage stabilizing diode D1, and a resistor R2; The resistor R2 is connected to the anode of the Zener diode D1, the first port of the MOS transistor Q2 is connected to the middle node between the resistor R2 and the Zener diode D1, and the third port of the MOS transistor Q2 is connected to the cathode of the Zener diode D1.

10. An armored vehicle power supply overvoltage protection circuit according to claim 9, characterized in that: The model of the MOS tube Q2 is HSU70P06, and the model of the voltage regulator diode D1 is MMSZ5243B.

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