Airborne equipment 270V large-current surge impact current suppression circuit

Abstract

The utility model relates to the technical field of surge current suppression of airborne equipment, and discloses a 270V large-current surge impact current suppression circuit for airborne equipment, which comprises an input charging circuit and a field-effect tube on-off control circuit, the field effect transistor on-off control circuit comprises a field effect transistor simultaneous starting circuit and a surge current suppression circuit. When the 270V power supply circuit is turned on, the power supply input end charges the capacitor, the field effect transistor is controlled to be turned off through the triode, the field effect transistor in the surge current suppression circuit is in a turned-off state, current flows through the resistor before the capacitor is fully charged, the circuit current is limited through the resistor, and the capacitor is charged at the moment; after the capacitor is fully charged, the field-effect tube is controlled to be conducted through the triode, current in the circuit flows through the field-effect tube, and the circuit returns to normal; the circuit not only realizes the simultaneous on-off of the parallel field effect transistors, but also effectively suppresses the surge current in the circuit.

Description

Technical Field

[0001] The utility model relates to the technical field of surge current suppression for airborne equipment, and particularly to a 270V large-current surge impact current suppression circuit for airborne equipment. Background Technique

[0002] With the wide application of 270V power supplies and electronic devices in airborne equipment, in high-power products such as switching power supplies, there are usually large capacitors. At the moment when the power supply is started, the current for charging the subsequent capacitors is relatively large, and a large peak current will appear. This kind of current is called surge current.

[0003] The surge current can usually reach dozens of amperes or even thousands of amperes. If such a large current is not restricted or suppressed, it will cause an instantaneous voltage drop of the input voltage and lead to easy loss and reduced lifespan of the electronic components in the power supply product.

[0004] For the surge current of the 270V power supply, currently, in the surge current suppression method, a field-effect transistor is used to switch through a resistor to suppress it, but the field-effect transistor has a power limit.

[0005] In order to increase the current magnitude in the circuit, parallel field-effect transistors are usually used, but there is a problem that the parallel field-effect transistors cannot be turned off and started simultaneously. How to design a surge suppression circuit that takes into account reliability, enables the field-effect transistors to start and turn off simultaneously, and provides a high-power suppression circuit has become the key.

[0006] Therefore, we need to propose a 270V large-current surge impact current suppression circuit for airborne equipment, which addresses the deficiencies of the traditional 270V power supply surge voltage suppression circuit, takes into account high power and circuit reliability, and at the same time ensures that the field-effect transistors start and switch simultaneously. Content of the Utility Model

[0007] The purpose of the utility model is to provide a 270V large-current surge impact current suppression circuit for airborne equipment. Through the design of the field-effect transistor on-off control circuit, when the surge current comes, multiple field-effect transistors are turned off simultaneously, and the current flows through the resistor. The resistor restricts the circuit current, making the circuit current and voltage stable at the required values, realizing the simultaneous on-off of the parallel field-effect transistors and effectively suppressing the surge current in the circuit, so as to solve the problems raised in the above background technique.

[0008] To achieve the above purpose, the utility model provides the following technical solution: A 270V large-current surge impact current suppression circuit for airborne equipment, comprising:

[0009] An input charging circuit connected to the 270V power supply input terminal for smoothing the voltage and restricting the surge current;

[0010] A field-effect transistor on / off control circuit connected to the 270V power supply output terminal for controlling the conduction or cutoff of the field-effect transistor;

[0011] The field-effect transistor on / off control circuit includes:

[0012] A field-effect transistor simultaneous startup circuit for driving all field-effect transistors to conduct or cutoff synchronously;

[0013] A surge current suppression circuit connected to the 270V power supply output terminal for reducing the surge current in the circuit through a resistor;

[0014] The input charging circuit, the field-effect transistor simultaneous startup circuit, and the surge current suppression circuit are connected in sequence.

[0015] Preferably, the input charging circuit includes a series-connected resistor R1 and resistor R6, one end of the resistor R1 is connected to the positive input terminal of the 270V power supply, the resistor R6 is connected to the negative input terminal of the 270V power supply, and a capacitor C1 is connected in parallel with the resistor R6.

[0016] Preferably, the field-effect transistor simultaneous startup circuit includes a triode Q1 and a triode Q2. A resistor R7 is connected between the base and emitter of the triode Q1, a zener diode D3 is connected between the collector and emitter of the triode Q1, and a zener diode D1 is connected between the base of the triode Q1 and the connection terminal of the resistor R1 and the resistor R6.

[0017] Preferably, a resistor R2 is connected to the collector of the triode Q1, one end of the resistor R2 is connected to the resistor R1, and a resistor R5 and a diode D2 are connected in series between the base of the triode Q2 and the collector of the triode Q1.

[0018] Preferably, the surge current suppression circuit includes a parallel-connected field-effect transistor Q3 and a field-effect transistor Q4. A resistor R4 and a resistor R9 are connected between the gates of the field-effect transistor Q3 and the field-effect transistor Q4. The source of the field-effect transistor Q3 is connected to the source of the field-effect transistor Q4, and the drain of the field-effect transistor Q3 is connected to the drain of the field-effect transistor Q4.

[0019] Preferably, the connection terminal of the resistor R4 and the resistor R9 is connected to the collector of the triode Q2. The connection terminal of the source of the field-effect transistor Q3 and the source of the field-effect transistor Q4 is connected to the emitter of the triode Q2. The connection terminal of the drain of the field-effect transistor Q3 and the drain of the field-effect transistor Q4 is connected to the negative output terminal of the 270V power supply.

[0020] Preferably, the surge current suppression circuit further includes a resistor R8 connected between the collector and the emitter of the triode Q2, a resistor R10 connected in parallel between the source and the drain of the field effect transistor Q4, a resistor R3 is also connected to the collector of the triode Q2, the resistor R3 is connected to the resistor R2, one end of the resistor R3 is connected to the positive output terminal of the 270V power supply, and a voltage stabilizing diode D4 is arranged in parallel on the resistor R8.

[0021] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0022] Through the design of the field effect transistor on-off control circuit of the present invention, when the 270V power supply circuit is turned on, the power input terminal charges the capacitor. The triode controls the field effect transistor to turn off, and the field effect transistor in the surge current suppression circuit is in the off state. Before the capacitor is fully charged, the current flows through the resistor, and the resistor limits the circuit current. At this time, the capacitor is charged;

[0023] After the capacitor is fully charged, the triode controls the field effect transistor to turn on, and the current in the circuit flows through the field effect transistor, and the circuit returns to normal; this circuit not only realizes the simultaneous on-off of the parallel field effect transistors, but also effectively suppresses the surge current in the circuit. Description of the Drawings

[0024] Figure 1 It is the circuit diagram of the present invention. Detailed Embodiments

[0025] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

[0026] Please refer to Figure 1 , the present invention provides a technical solution: an airborne equipment 270V large current surge impact current suppression circuit, including:

[0027] An input charging circuit connected to the 270V power input terminal for smoothing the voltage and limiting the surge current;

[0028] A field effect transistor on-off control circuit connected to the 270V power output terminal for controlling the conduction or cut-off of the field effect transistor;

[0029] The field effect transistor on-off control circuit includes:

[0030] A field effect transistor simultaneous startup circuit for driving all field effect transistors to conduct or cut off synchronously;

[0031] A surge current suppression circuit connected to the 270V power supply output terminal and reducing the current in the circuit through a resistor;

[0032] When the 270V power supply circuit is turned on, the power input terminal charges the capacitor. The triode controls the field effect transistor to turn off, and the field effect transistor in the surge current suppression circuit is in the off state. Before the capacitor is fully charged, the current flows through the resistor, and the resistor limits the circuit current. At this time, the capacitor is charged;

[0033] After the capacitor is fully charged, the triode controls the field effect transistor to turn on, and the current in the circuit flows through the field effect transistor, and the circuit returns to normal.

[0034] The input charging circuit, the field effect transistor simultaneous startup circuit, and the surge current suppression circuit are connected in sequence.

[0035] The input charging circuit includes a series-connected resistor R1 and resistor R6. One end of the resistor R1 is connected to the positive input terminal of the 270V power supply, the resistor R6 is connected to the negative input terminal of the 270V power supply, and a capacitor C1 is connected in parallel with the resistor R6.

[0036] The field effect transistor simultaneous startup circuit includes a triode Q1 and a triode Q2. A resistor R7 is connected between the base and the emitter of the triode Q1, a zener diode D3 is connected between the collector and the emitter of the triode Q1, and a zener diode D1 is connected between the base of the triode Q1 and the connection terminal of the resistor R1 and the resistor R6.

[0037] A resistor R2 is connected to the collector of the triode Q1. One end of the resistor R2 is connected to the resistor R1. A resistor R5 and a diode D2 are connected in series between the base of the triode Q2 and the collector of the triode Q1.

[0038] The surge current suppression circuit includes a parallel-set field effect transistor Q3 and a field effect transistor Q4. A resistor R4 and a resistor R9 are connected between the gates of the field effect transistor Q3 and the field effect transistor Q4. The source of the field effect transistor Q3 is connected to the source of the field effect transistor Q4, and the drain of the field effect transistor Q3 is connected to the drain of the field effect transistor Q4.

[0039] The connection terminal of the resistor R4 and the resistor R9 is connected to the collector of the triode Q2. The connection terminal of the source of the field effect transistor Q3 and the source of the field effect transistor Q4 is connected to the emitter of the triode Q2. The connection terminal of the drain of the field effect transistor Q3 and the drain of the field effect transistor Q4 is connected to the negative output terminal of the 270V power supply.

[0040] The surge current suppression circuit further includes a resistor R8 connected between the collector and emitter of the triode Q2, and a resistor R10 connected in parallel between the source and drain of the field effect transistor Q4. A resistor R3 is also connected to the collector of the triode Q2. The resistor R3 is connected to the resistor R2. One end of the resistor R3 is connected to the positive output terminal of the 270V power supply. A zener diode D4 is connected in parallel with the resistor R8.

[0041] By detecting the input voltage, the conduction or cutoff of the field effect transistors Q3 and Q4 is controlled, and the resistor R8 is used to limit the circuit current to ensure the normal operation of the subsequent devices.

[0042] The input terminal of the 270V power supply charges the capacitor C1. By selecting appropriate values for the capacitor C1 and the resistor R1, during the charging process, the base of the triode Q1 does not obtain sufficient voltage, and the CE (collector and emitter of the triode Q1) is not conducting. A stable voltage is obtained across the zener diode D3, and the base of the triode Q2 obtains voltage, causing the CE terminal (collector and emitter of the triode Q2) of the triode Q2 to conduct. The voltage division of the resistor R8 is equivalent to being short-circuited. The gates of the field effect transistors Q3 and Q4 do not obtain voltage, and the field effect transistors Q3 and Q4 are turned off. The circuit current passes through the resistor R10 to suppress the surge current.

[0043] After the 270V power supply fully charges the capacitor C1, at this time, the resistors R1 and R6 perform voltage division. The base of the triode Q1 obtains sufficient voltage, and the CE (collector and emitter of the triode Q1) conducts. The base of the triode Q2 does not obtain sufficient voltage, and the CE terminal (collector and emitter of the triode Q2) of the triode Q2 does not conduct. The voltage division of the resistors R3 and R8 causes the gates of the field effect transistors Q3 and Q4 to obtain the voltage division of R8, and the field effect transistors Q3 and Q4 conduct, and the current flows through the field effect transistors Q3 and Q4.

[0044] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An in-aircraft equipment 270V high-current surge impact current suppression circuit, characterized in that, Comprising: An input charging circuit connected to the 270V power input terminal for smoothing the voltage and limiting the inrush current; A field-effect transistor on / off control circuit connected to the 270V power output terminal for controlling the conduction or cutoff of the field-effect transistor; The field-effect transistor on / off control circuit includes: A field-effect transistor simultaneous startup circuit for driving all field-effect transistors to conduct or cutoff synchronously; A surge current suppression circuit connected to the 270V power output terminal for reducing the current in the circuit through a resistor; The input charging circuit, the field-effect transistor simultaneous startup circuit, and the surge current suppression circuit are connected in sequence.

2. The 270V high-current surge impact current suppression circuit for an airborne device according to claim 1, characterized in that: The input charging circuit includes a series-connected resistor R1 and resistor R6, and one end of the resistor R1 is connected to the positive input terminal of the 270V power supply, the resistor R6 is connected to the negative input terminal of the 270V power supply, and a capacitor C1 is connected in parallel with the resistor R6.

3. An in-air equipment 270V high-current surge impact current suppression circuit according to claim 2, characterized in that: The field-effect transistor simultaneous startup circuit includes a triode Q1 and a triode Q2. A resistor R7 is connected between the base and the emitter of the triode Q1, a zener diode D3 is connected between the collector and the emitter of the triode Q1, and a zener diode D1 is connected between the base of the triode Q1 and the connection terminal of the resistor R1 and the resistor R6.

4. An in-aircraft equipment 270V high-current surge impact current suppression circuit according to claim 3, characterized in that: A resistor R2 is connected to the collector of the triode Q1, one end of the resistor R2 is connected to the resistor R1, and a resistor R5 and a diode D2 are connected in series between the base of the triode Q2 and the collector of the triode Q1.

5. An in-aircraft equipment 270V high-current surge impact current suppression circuit according to claim 4, characterized in that: The surge current suppression circuit includes a parallel-connected field-effect transistor Q3 and a field-effect transistor Q4. A resistor R4 and a resistor R9 are connected between the gate of the field-effect transistor Q3 and the gate of the field-effect transistor Q4. The source of the field-effect transistor Q3 is connected to the source of the field-effect transistor Q4, and the drain of the field-effect transistor Q3 is connected to the drain of the field-effect transistor Q4.

6. An in-aircraft equipment 270V high-current surge impact current suppression circuit according to claim 5, characterized in that: The connection terminal of the resistor R4 and the resistor R9 is connected to the collector of the triode Q2. The connection terminal of the source of the field-effect transistor Q3 and the source of the field-effect transistor Q4 is connected to the emitter of the triode Q2. The connection terminal of the drain of the field-effect transistor Q3 and the drain of the field-effect transistor Q4 is connected to the negative output terminal of the 270V power supply.

7. An in-aircraft equipment 270V high-current surge impact current suppression circuit according to claim 6, wherein: The surge current suppression circuit further includes a resistor R8 connected between the collector and the emitter of the triode Q2, a resistor R10 connected in parallel between the source and the drain of the field-effect transistor Q4, a resistor R3 is also connected to the collector of the triode Q2, the resistor R3 is connected to the resistor R2, one end of the resistor R3 is connected to the positive output terminal of the 270V power supply, and a zener diode D4 is connected in parallel with the resistor R8.

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