Output port self-recovery short-circuit protection circuit of generator set controller

Abstract

The utility model belongs to the technical field of short-circuit protection, and particularly relates to an output port self-recovery short-circuit protection circuit of a generator set controller, which comprises an output control module and an output protection module. The output control module circuit comprises a relay RLY1 and a signal input circuit. The output protection module circuit comprises a relay RLY2, a diode D4, a triode Q2, a TVS tube D2 and a resistor R2. One end of a coil of the relay RLY2 is connected to a collector electrode of the triode Q2 and a cathode of the diode D4, the other end of the coil of the relay RLY2 is connected to an anode of the diode D4 and a GND, a common end contact of the relay RLY2 is connected to one end of the resistor R2, the other end of the resistor R2 is connected to a normally open contact of the relay RLY1, and the normally open contact of the relay RLY2 is connected to the anode of the diode D4. The normally open contact of the relay RLY2 is suspended, and the normally closed contact of the relay RLY2 is connected to the output port and the base electrode of the triode Q2.

Description

TECHNICAL FIELD

[0001] The utility model belongs to short -circuit protection technical field, and specifically relates to a kind of output port self-recovery short-circuit protection circuit of generator set controller. BACKGROUND

[0002] In diesel generator set controller, according to function, output port can be divided into four categories: fuel relay output port, starting relay output port, programmable active relay output port and programmable passive relay output port etc..Among them, fuel relay output port, starting relay output port and programmable active relay output port are active output type, and output voltage is power supply voltage, and these output ports will power directly connected to load for power supply when using.However, generator set controller cannot directly detect the short circuit condition of load, and cannot quickly close output port when load is short-circuited, which may cause load damage.To solve the above problems, a new technical scheme needs to be found. SUMMARY

[0003] The utility model aims at providing a kind of output port self-recovery short-circuit protection circuit of generator set controller, can automatically detect the short circuit of generator set controller outside and disconnect output, and can be automatically attracted and output after the disappearance of external short circuit.

[0004] To achieve the above object, the technical scheme of the utility model is as follows: a kind of output port self-recovery short-circuit protection circuit of generator set controller is composed of output control module and output protection module;The output control module circuit includes: relay RLY1 and signal input circuit;

[0005] The coil of the relay RLY1 is connected to the output end of signal input circuit, the common end contact of the relay RLY1 is connected to second power supply, the normally open contact of the relay RLY1 is connected to the output protection module, and the normally closed contact of the relay RLY1 is suspended;

[0006] The output protection module circuit includes: relay RLY2, diode D4, triode Q2 and resistance R2;

[0007] One end of the coil of the relay RLY2 is connected to the collector of triode Q2 and the cathode of diode D4, the other end of the coil of the relay RLY2 is connected to the anode of diode D4 and GND, the common end contact of the relay RLY2 is connected to one end of resistance R2, the other end of resistance R2 is connected to the normally open contact of the relay RLY1, the normally open contact of the relay RLY2 is suspended, and the normally closed contact of the relay RLY2 is connected to output port and the base of triode Q2.

[0008] Further, the signal input circuit comprises a diode D3, a triode Q1 and a resistor R3; one end of the resistor R3 is connected to a control pin of the MCU, the other end is connected to the base of the triode Q1, one end of the coil of the relay RLY1 is connected to the cathode of the diode D3, the output end of the first power supply, the other end of the coil of the relay RLY1 is connected to the anode of the diode D3 and the collector of the triode Q1, the emitter of the triode Q1 is connected to GND.

[0009] Further, the capacitor C2 and the resistor R4 are connected in series between the resistor R3 and the control pin of the MCU, one end of the capacitor C2 and the resistor R4 is connected to the resistor R3 and the control pin of the MCU, the other end of the capacitor C2 and the resistor R4 is connected to GND.

[0010] Further, the capacitor C1 is connected in series between the cathode of the diode and the first power supply, one end of the capacitor C1 is connected to the cathode of the diode D3 and the output end of the first power supply, the other end of the capacitor C1 is connected to GND.

[0011] Further, the resistor R1 is connected in series between the normally closed contact of the relay RLY2 and the output port, and the resistor R5 is connected in series between the normally closed contact of the relay RLY2 and the base of the triode Q2.

[0012] Further, the diode D1 and the TVS tube D2 are also connected in series between the resistor R1 and the output port, the resistor R1 is connected to the anode of the diode D1, the cathode of the diode D1 is connected to the output port and one end of the TVS tube D2, the other end of the TVS tube D2 is connected to GND.

[0013] Further, the voltage of the first power supply is 5V, the voltage of the second power supply is 24V, the relay RLY1 adopts a 5V single-pole double-throw relay, and the relay RLY2 adopts a 24V single-pole double-throw relay.

[0014] Further, the diode D4 adopts a switching diode 1N4148W, and the triode Q2 adopts a PNP triode S8550.

[0015] Further, the diode D3 adopts a switching diode 1N4148W, and the triode Q1 adopts an NPN triode S8050.

[0016] Further, the diode D1 adopts a general diode M7, and the TVS tube D2 adopts a bidirectional TVS tube SMAJ60CA.

[0017] Compared with the prior art, the utility model discloses a relay and triode combination short circuit protection function to the output port, can automatically detect whether the short circuit situation exists outside the motor group controller, when the short circuit situation exists, the output port of motor group controller will be in the disconnected state, when the external short circuit disappears, will automatically reabsorb and output, the protection circuit of the utility model has the advantages of simple structure, high reliability. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 It is the circuit schematic diagram of the output port self -restoring short circuit protection circuit of the generator set controller of the utility model; DETAILED DESCRIPTION

[0019] The utility model is further explained below in combination with the drawings, obviously, the described embodiment only is a part embodiment of the utility model, not all the embodiment. The language such as "1 foot, 2 foot, 3 foot..." etc. in the specification, only for the convenience of with the specification drawing provided by the application cooperation narration, and not to limit the scope of the utility model can be implemented, in the application, the 1 foot of three -stage tube Q1, Q2 is base, 2 foot is emitter, 3 foot is collector;The 1 foot of relay RLY1, RLY2 is one end of coil, 2 foot is the other end of coil, 3 foot is common terminal, 4 foot is normally open contact, 5 foot is normally closed contact. If the naming of the lead changes or adjusts, under the condition of no substantial change of technical content, it is also regarded as the scope of the utility model can be implemented.

[0020] The utility model discloses a kind of output port self -restoring short circuit protection circuit of generator set controller, it includes relay RLY1, RLY2, diode D1, D3, D4, triode Q1, Q2, TVS pipe D2, resistance R1, R2, R3, R4, R5, capacitor C1, C2 composition. Among them, the relay RLY1 uses 5V single pole double throw relay, the relay RLY2 uses 24V single pole double throw relay, the diode D1 uses general diode M7, the diode D3, D4 uses switch diode 1N4148W, the triode Q1 uses NPN type triode S8050, the triode Q2 uses PNP type triode S8550, the TVS pipe D2 uses bidirectional TVS pipe SMAJ60CA.

[0021] The output port self -restoring short circuit protection circuit of the generator set controller can be divided into two modules of output control module and output protection module according to function.

[0022] The output control module circuit includes: relay RLY1 and signal input circuit;Wherein signal input circuit includes: diode D3, triode Q1, capacitor C1, C2, resistance R3, R4.

[0023] The 1 pin of the relay RLY1 is connected to the cathode of the diode D3, a first power supply (VCC_5V) and one end of the capacitor C1, and the other end of the capacitor C1 is connected to GND. The 2 pin of the relay RLY1 is connected to the anode of the diode D3 and the 3 pin of the triode Q1, the 2 pin of the triode Q1 is connected to GND, the 1 pin of the triode Q1 is connected to one end of the resistor R3, the other end of the resistor R3 is connected to a control pin (MCU_GPIO) of the MCU, the capacitor C2 and one end of the resistor R4, and the other end of the capacitor C2 and the resistor R4 is connected to GND. The 3 pin of the relay RLY1 is connected to a second power supply (DC24V_IN), and the 4 pin (normally open contact) of the relay RLY1 is connected to one end of the resistor R2 and the 2 pin of the triode Q2, and the 5 pin (normally closed contact) of the relay RLY1 is suspended.

[0024] The output protection module circuit comprises a relay RLY2, diodes D1 and D4, a triode Q2, a TVS tube D2, resistors R1, R2 and R5. The 1 pin of the relay RLY2 is connected to the 3 pin of the triode Q2 and the cathode of the diode D4, the 2 pin of the relay RLY2 is connected to the anode of the diode D4 and GND, the 3 pin of the relay RLY2 is connected to the other end of the resistor R2, the 4 pin (normally open contact) of the relay RLY2 is suspended, the 5 pin (normally closed contact) of the relay RLY2 is connected to one end of the resistors R1 and R5, the other end of the resistor R1 is connected to the anode of the diode D1, the cathode of the diode D1 is connected to an output and one end of the TVS tube D2, the other end of the TVS tube D2 is connected to GND, and the other end of the resistor R5 is connected to the 1 pin of the triode.

[0025] The first power supply (VCC_5V) is a power supply of the circuit, and the second power supply (DC24V_IN) is a power supply for external output. The input signal of the circuit is an MCU_GPIO signal sent by a single-chip microcomputer, and the signal is a 3.3V TTL signal. The output signal of the circuit is an OUTPUT signal, and the signal is a 24V voltage output.

[0026] In actual use, the resistors R1 and R5 are current limiting resistors, which respectively protect the triode Q2 and limit the current output to the outside. The diodes D3 and D4 can protect the relay coil, and the diode D1 is used to prevent external current from flowing back to damage the circuit. The TVS tube D2 is used to prevent external instantaneous high voltage from damaging the circuit.

[0027] The circuit has three states when working: normal disconnection, normal output and abnormal non-output.

[0028] When the MCU_GPIO signal of the MCU is a low level signal, the signal reaches the transistor Q1 after being filtered by the capacitor C2 and the current-limiting resistor R3. At this time, the base-emitter voltage Ube of the transistor Q1 is less than its opening voltage, and the transistor is in a cut-off state. No current flows through the coil of the 1.2 pin of the relay RLY1, and the relay RLY1 is not attracted. At this time, the 3 pin of the relay RLY1 is connected to the 5 pin, and the 4 pin has no 24V entering. The entire circuit is in a non-output state.

[0029] When the MCU_GPIO signal of the MCU is a high level signal, the signal reaches the transistor Q1 after being filtered by the capacitor C2 and the current-limiting resistor R3. At this time, the base-emitter voltage Ube of the transistor Q1 is greater than its opening voltage, and the transistor is in a conducting state. A 5V current flows through the coil of the 1.2 pin of the relay RLY1, and the relay RLY1 is attracted. At this time, the 3 pin of the relay RLY1 is connected to the 4 pin, and the 24V power supply enters the next stage of circuit. The 24V power supply passes through the sampling resistor R2. Since the R2 resistor is extremely small, the voltage drop across it is much smaller than the opening voltage of the transistor Q2, and the transistor is in a cut-off state. No current flows through the coil of the 1.2 pin of the relay RLY2, and the relay RLY2 is not attracted. At this time, the 3 pin of the relay RLY2 is connected to the 5 pin, and the 24V power supply begins to output externally.

[0030] When the external load is in a short circuit condition, the DC 24V power supply is short-circuited, and the current instantaneously increases. The voltage drop across the sampling resistor R2 suddenly increases. At this time, the voltage drop is greater than the opening voltage of the transistor Q2, and the transistor is in a conducting state. At this time, the relay coil is energized, the relay RLY1 is attracted, the 3 pin of the relay RLY2 is disconnected from the 5 pin, and the external 24V power supply is stopped, realizing the short circuit protection function.

[0031] The principle of the short circuit self-recovery function is as follows: When the external short circuit occurs, the circuit stops outputting. At this time, the external load is still in a short circuit state, which can be equivalent to being directly connected to GND. That is, the base voltage of the transistor Q2 is 0V, and the emitter voltage of the transistor Q2 is 24V. The base-emitter voltage Ube of the transistor Q2 is much greater than the opening voltage, and the transistor Q2 is always in an open state. The relay RLY2 is always in an attracted state, and the external 24V output is stopped. When the external short circuit disappears, the ground connection of the base of the transistor Q2 disappears. At this time, the base-emitter voltage Ube of the transistor Q2 will be less than the opening voltage, and the transistor Q2 will become a cut-off state. The relay RLY2 will become a non-attracted state. At this time, the 3 pin of the relay RLY2 continues to be connected to the 5 pin, and the entire circuit will continue to output 24V power supply.

[0032] The above merely describes preferred embodiments of the present application, and thus equivalent changes or modifications made in accordance with the structure, features and principles described in the patent application scope of the present application are included in the patent application protection scope of the present application.

Claims

1. A self-resetting short-circuit protection circuit for the output port of a generator set controller, characterized in that, It consists of an output control module and an output protection module; the output control module circuit includes: a relay RLY1 and a signal input circuit; The coil of relay RLY1 is connected to the output terminal of the signal input circuit, the common terminal contact of relay RLY1 is connected to the second power supply, the normally open contact of relay RLY1 is connected to the output protection module, and the normally closed contact of relay RLY1 is left floating. The output protection module circuit includes: relay RLY2, diode D4, transistor Q2, and resistor R2; One end of the coil of relay RLY2 is connected to the collector of transistor Q2 and the cathode of diode D4, and the other end of the coil of relay RLY2 is connected to the anode of diode D4 and GND. The common terminal contact of relay RLY2 is connected to one end of resistor R2, and the other end of resistor R2 is connected to the normally open contact of relay RLY1. The normally open contact of relay RLY2 is left floating, and the normally closed contact of relay RLY2 is connected to the output port and the base of transistor Q2.

2. The self-resetting short-circuit protection circuit for the output port of a generator set controller according to claim 1, characterized in that, The signal input circuit includes a diode D3, a transistor Q1, and a resistor R3; one end of the resistor R3 is connected to the control pin of the MCU, and the other end is connected to the base of the transistor Q1. One end of the coil of the relay RLY1 is connected to the cathode of the diode D3 and the first power supply output terminal, and the other end of the coil of the relay RLY1 is connected to the anode of the diode D3 and the collector of the transistor Q1. The emitter of the transistor Q1 is connected to GND.

3. The self-resetting short-circuit protection circuit for the output port of a generator set controller according to claim 2, characterized in that, A capacitor C2 and a resistor R4 are connected in series between the resistor R3 and the control pin of the MCU. One end of the capacitor C2 and the resistor R4 is connected to the resistor R3 and the control pin of the MCU, and the other end of the capacitor C2 and the resistor R4 is connected to GND.

4. The self-resetting short-circuit protection circuit for the output port of a generator set controller according to claim 2, characterized in that, A capacitor C1 is connected in series between the cathode of the diode and the first power supply. One end of the capacitor C1 is connected to the cathode of the diode D3 and the output terminal of the first power supply, and the other end of the capacitor C1 is connected to GND.

5. The self-resetting short-circuit protection circuit for the output port of a generator set controller according to claim 1, characterized in that, A resistor R1 is connected in series between the normally closed contact of the relay RLY2 and the output port, and a resistor R5 is connected in series between the normally closed contact of the relay RLY2 and the base of the transistor Q2.

6. The self-resetting short-circuit protection circuit for the output port of a generator set controller according to claim 5, characterized in that, A diode D1 and a TVS diode D2 are connected in series between the resistor R1 and the output port. The resistor R1 is connected to the anode of the diode D1, the cathode of the diode D1 is connected to the output port and one end of the TVS diode D2, and the other end of the TVS diode D2 is connected to GND.

7. The self-resetting short-circuit protection circuit for the output port of a generator set controller according to claim 2, characterized in that, The first power supply voltage is 5V, the second power supply voltage is 24V, the relay RLY1 is a 5V single-pole double-throw relay, and the relay RLY2 is a 24V single-pole double-throw relay.

8. The self-resetting short-circuit protection circuit for the output port of a generator set controller according to claim 1, characterized in that, The diode D4 is a switching diode 1N4148W, and the transistor Q2 is a PNP transistor S8550.

9. The output port self-resetting short-circuit protection circuit of a generator set controller according to claim 2, characterized in that, The diode D3 is a switching diode 1N4148W, and the transistor Q1 is an NPN transistor S8050.

10. The output port self-resetting short-circuit protection circuit of a generator set controller according to claim 6, characterized in that, The diode D1 is a general-purpose diode M7, and the TVS diode D2 is a bidirectional TVS diode SMAJ60CA.

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