CN205385282U - Voltage controller is owed in outage time delay - Google Patents

Abstract

The utility model relates to a power-off delay and undervoltage controller, which includes a filter circuit, the input end of which is connected to an external power grid, and the output end of the filter circuit is connected with a step-down rectification circuit, a power supply circuit and a voltage signal acquisition circuit; Processor, the microprocessor is connected with the voltage signal acquisition circuit and a delay adjustment device; the power supply charging and discharging circuit, the charging terminal is connected with the output terminal of the power supply circuit, and the discharging terminal is connected with the microprocessor; the coil control circuit The input end of the input terminal is connected with the output end of the step-down rectification circuit, and the control end of the coil control circuit is connected with the microprocessor; the capacitor charging and discharging circuit, its charging end is connected with the output end of the step-down rectification circuit, and the discharge end is connected with the output end of the step-down rectification circuit. The release coil QT is connected. Through the coil control circuit, the capacitor charging and discharging circuit and the power supply charging and discharging circuit, the normal power supply of the microprocessor and the release coil QT is satisfied during the time delay control, thereby achieving the time delay effect.

Description

A power-off delay undervoltage controller

technical field

The utility model relates to the technical field of undervoltage protection, in particular to a power-off delay undervoltage controller.

Background technique

In power supply circuits, undervoltage faults often occur. When an undervoltage fault occurs, if the protective measures cannot be taken in time, when the voltage exceeds the maximum withstand voltage of some equipment, it will damage the equipment and cause huge losses. The undervoltage protector is a device used to reduce the loss caused by this situation. It can disconnect the circuit in time to protect the equipment when it detects an undervoltage fault in the power supply circuit.

Generally speaking, the equipment can withstand short-term undervoltage operation. If the undervoltage restores normal power supply during this period, the equipment will not be damaged. However, in such a case, power failure may cause data loss, production stagnation, the losses caused have been expanded instead. The current undervoltage protection products do not have the function of intelligent delay monitoring and choosing whether to power off.

Utility model content

The technical problem to be solved by the utility model is to provide a power failure delay undervoltage controller suitable for delay tripping when the power supply line is undervoltage or power failure.

In order to solve the above technical problems, the utility model provides a power-off delay undervoltage controller, which includes a filter circuit, the input end of which is connected to the external power grid, and the output end of the filter circuit is connected to the step-down rectifier circuit, the power supply circuit and the voltage The signal acquisition circuit is connected; the microprocessor, the microprocessor is connected with the voltage signal acquisition circuit and a delay adjustment device; the power supply charging and discharging circuit, the charging terminal is connected with the output terminal of the power supply circuit, and the discharging terminal is connected with the microprocessor The coil control circuit includes the release coil QT and the first switch tube Q2 for controlling the release coil QT to be energized or de-energized, the input terminal of the release coil QT and the step-down rectification circuit The output terminal of the first switching tube Q2 is connected to the microprocessor; the capacitor charging and discharging circuit, the charging terminal is connected to the output terminal of the step-down rectification circuit, and the discharging terminal is connected to the release coil QT.

The capacitor charging and discharging circuit includes a first electrolytic capacitor C6, a first voltage stabilizing diode Z1, a second diode D3, a third constant current diode D4, a fourth diode D5, a first resistor R2 and a second switch Tube Q1; where the anode of the first electrolytic capacitor C6 and the cathode of the first Zener diode Z1 are connected to the output terminal of the step-down rectifier circuit, and the cathode of the first electrolytic capacitor C6 is connected to the cathode of the second diode D3 and the first voltage regulator The anode of the diode Z1, the anode of the second diode D3 are connected to the anode of the third constant current diode D4, and the cathode of the third constant current diode D4 is grounded; the input terminal of the first resistor R2 is connected to the anode of the first Zener diode Z1, The output terminal of the first resistor R2 is connected to the first terminal of the second switching tube Q1, the second terminal of the second switching tube Q1 is connected to the anode of the fourth diode D5, and the control terminal of the second switching tube Q1 is connected to the microprocessor , the cathode of the fourth diode D5 is grounded.

The power supply charging and discharging circuit includes a fifth diode D1, a sixth diode D2, a second resistor R1, and a second electrolytic capacitor C5, and the cathode of the fifth diode D1 is connected to one end of the second resistor R1 , the other end of the second resistor R1 is connected to the positive pole of the second electrolytic capacitor C5, and the negative pole of the second electrolytic capacitor C5 is grounded; the anode of the fifth diode D1 is connected to the cathode of the sixth diode D2, and the sixth The anode of the diode D2 is connected to the anode of the second electrolytic capacitor C5, and the cathode of the sixth diode D2 is connected to the power supply terminal of the microprocessor.

The step-down rectifier circuit includes a third electrolytic capacitor C4 and a rectifier bridge, the anode of the third electrolytic capacitor C4 is connected to the output end of the rectifier bridge, and the cathode of the third electrolytic capacitor C4 is grounded.

The first switch tube Q2 is a transistor or a MOS tube.

The second switch tube Q1 is a transistor or a MOS tube.

The beneficial effects of the utility model are: the utility model satisfies the normal power supply of the microprocessor and the release coil QT during the delay control through the coil control circuit, the capacitor charging and discharging circuit and the power supply charging and discharging circuit, thereby achieving In addition, the constant current diode is preferably used to make the discharge current of the electrolytic capacitor constant after power off. This constant discharge ensures that the release coil QT can be in a longer delay pull-in state to obtain more Good working effect.

Description of drawings

Fig. 1 is a circuit block diagram of a power-off delay undervoltage controller of the present invention.

detailed description

Below in conjunction with accompanying drawing, the utility model embodiment is further described:

As shown in the figure, a power-off delay undervoltage controller includes a filter circuit, the input end of which is connected to an external power grid, and the output end of the filter circuit is connected to a step-down rectifier circuit, a power supply circuit and a voltage signal acquisition circuit; Microprocessor, the microprocessor is connected with the voltage signal acquisition circuit and a delay adjustment device; the power supply charging and discharging circuit, its charging end is connected with the output end of the power supply circuit, and the discharge end is connected with the microprocessor; the coil control The circuit includes a release coil QT and a first switch tube Q2 for controlling the energization or de-energization of the release coil QT, the input end of the release coil QT is connected to the output end of the step-down rectification circuit, The control end of the first switching tube Q2 is connected to the microprocessor; the charging end of the capacitor charging and discharging circuit is connected to the output end of the step-down rectification circuit, and the discharging end is connected to the release coil QT.

Wherein, the delay adjustment circuit can adopt a timer, or a delay circuit disclosed in Chinese patent literature (application publication number: CN102332899A); the technical solution for the microprocessor to obtain the current voltage value through the voltage signal acquisition circuit is in It has been disclosed in the prior art, and will not be described in detail here; the voltage signal acquisition circuit includes a step-down circuit and an AD module connected to the step-down circuit. The module; the microprocessor can adopt C51 series single-chip microcomputer; the power supply circuit is realized by step-down circuit and 7805 regulator tube, and 7812 can also be added according to needs to meet the needs of different integrated circuits.

Specifically, the first switching tube Q2 can use a triode or a MOS tube to realize the switching function. If a triode is used, the first terminal is a collector, the second terminal is an emitter, and the control terminal is a base; if a MOS tube is used , then the first end is the D pole, the second end is the S pole, and the control end is the G pole.

The capacitor charging and discharging circuit includes a first electrolytic capacitor C6, a first voltage stabilizing diode Z1, a second diode D3, a third constant current diode D4, a fourth diode D5, a first resistor R2 and a second switch Tube Q1; where the anode of the first electrolytic capacitor C6 and the cathode of the first Zener diode Z1 are connected to the output terminal of the step-down rectifier circuit, and the cathode of the first electrolytic capacitor C6 is connected to the cathode of the second diode D3 and the first voltage regulator The anode of the diode Z1, the anode of the second diode D3 are connected to the anode of the third constant current diode D4, and the cathode of the third constant current diode D4 is grounded; the input terminal of the first resistor R2 is connected to the anode of the first Zener diode Z1, The output terminal of the first resistor R2 is connected to the first terminal of the second switching tube Q1, the second terminal of the second switching tube Q1 is connected to the anode of the fourth diode D5, and the control terminal of the second switching tube Q1 is connected to the microprocessor , the cathode of the fourth diode D5 is grounded. The second switching tube Q1 adopts a triode or a MOS tube. If a triode is used, the first terminal is a collector, the second terminal is an emitter, and the control terminal is a base; if a MOS tube is used, the first terminal is a collector. One end is D pole, the second end is S pole, and the control end is G pole.

The power supply charging and discharging circuit includes a fifth diode D1, a sixth diode D2, a second resistor R1, and a second electrolytic capacitor C5, and the cathode of the fifth diode D1 is connected to one end of the second resistor R1 , the other end of the second resistor R1 is connected to the positive pole of the second electrolytic capacitor C5, and the negative pole of the second electrolytic capacitor C5 is grounded; the anode of the fifth diode D1 is connected to the cathode of the sixth diode D2, and the sixth The anode of the diode D2 is connected to the anode of the second electrolytic capacitor C5, and the cathode of the sixth diode D2 is connected to the power supply terminal of the microprocessor.

The step-down rectifier circuit includes a third electrolytic capacitor C4 and a rectifier bridge, the anode of the third electrolytic capacitor C4 is connected to the output terminal of the rectifier bridge, and the cathode of the third electrolytic capacitor C4 is grounded for connecting the power grid AC high After the voltage passes through the step-down capacitor and the rectifier bridge, it is adjusted to a voltage capable of driving the action of the release coil QT, wherein the capacitor C3 can be a resistor.

The working process of the power-off delay undervoltage controller:

When the power is turned on, the second switching tube Q1 is not conducting, and when the voltage across the third electrolytic capacitor C4 reaches the set threshold value for the reliable operation of the coil, the first switching tube Q2 is conducting, and the release coil QT flows current , so that the undervoltage electromagnet action.

After the action, the second switch tube Q1 is turned on, the first electrolytic capacitor C6 is charged, the first voltage regulator diode Z1 ensures that the first electrolytic capacitor C6 will not be overcharged, and the first resistor R2 acts as a current limiter when charging.

When the undervoltage controller is powered off, the second electrolytic capacitor C5 of the power supply charging and discharging circuit ensures the normal operation of the microprocessor, and delays according to the set delay time. At this time, the first switch tube Q2 remains in the on state, and the second An electrolytic capacitor C6 discharges through the release coil QT, the first switch tube Q2, the third constant current diode D4, and the second diode D3, so as to ensure the normal pull-in state of the release coil QT, and the third constant current diode D4, to ensure that the current flowing through the release coil QT is constant, which can prolong the discharge time of the first electrolytic capacitor C6.

Working process of undervoltage controller:

The microprocessor detects whether the power supply voltage is normal through the voltage signal acquisition circuit. When the power supply voltage is normal, the output control command makes the first switch tube Q2 conduct, the release coil QT is in the pull-in state, and then the microprocessor outputs the control command to make the first switch tube Q2 conduct. The second switching tube Q1 is turned on to charge the first electrolytic capacitor C6; when the power supply voltage is undervoltage or cut off, the second electrolytic capacitor C5 in the power supply charging and discharging circuit ensures that the microprocessor is in a normal working state, and at the same time disconnects the first electrolytic capacitor C6. The second switching tube Q1 releases the charging state of the first electrolytic capacitor C6 and keeps the first switching tube Q2 in a conducting state. At this time, the first electrolytic capacitor C6 is immediately switched to a discharging state. In order to prolong the discharging time of the first electrolytic capacitor C6, The third constant current diode D4 is specially added, and the constant discharge of the first electrolytic capacitor C6 ensures that the coil is in a longer delay pull-in state. After the delay time is up, the microprocessor outputs an instruction to turn off the first switch tube Q2, so that The trip coil QT is in the released state.

The embodiments described above in conjunction with the accompanying drawings are only preferred implementations of the present utility model, rather than limiting the scope of protection of the present utility model. Any improvements made based on the spirit of the present utility model should fall within the scope of protection of the present utility model .

Claims (6)

1. a power cut off delay under-voltage controller, it is characterised in that including:

Filter circuit, its input is connected with external power grid, and the outfan of this filter circuit is connected with step-down rectifying circuit, power circuit and voltage signal acquisition circuit；Microprocessor, described microprocessor is connected with voltage signal acquisition circuit and a delay adjustment device；

Power supply charge-discharge circuit, its charging end is connected with the outfan of described power circuit, and discharge end is connected with microprocessor；

Coil control circuit, electric or dead electricity the first switching tube Q2 is obtained including trip coil QT with for controlling this trip coil QT, the input of trip coil QT is connected with the outfan of described step-down rectifying circuit, and the control end of the first switching tube Q2 is connected with microprocessor；

Capacitor charge and discharge circuit, its charging end is connected with the outfan of described step-down rectifying circuit, and discharge end is connected with trip coil QT.

2. a kind of power cut off delay under-voltage controller according to claim 1, it is characterised in that: described capacitor charge and discharge circuit it include the first electrochemical capacitor C6, the first Zener diode Z1, the second diode D3, the 3rd current regulator diode D4, the 4th diode D5, the first resistance R2 and second switch pipe Q1；Wherein the anode of the first electrochemical capacitor C6 and the negative electrode of the first Zener diode Z1 connect the outfan of step-down rectifying circuit, the negative electrode of the first electrochemical capacitor C6 connects the negative electrode of the second diode D3 and the anode of the first Zener diode Z1, the anode of the second diode D3 connects the anode of the 3rd current regulator diode D4, the minus earth of the 3rd current regulator diode D4；The anode of the input termination first Zener diode Z1 of the first resistance R2, first end of the output termination second switch pipe Q1 of the first resistance R2, the anode of second termination the 4th diode D5 of second switch pipe Q1, the control end of second switch pipe Q1 is connected with microprocessor, the minus earth of the 4th diode D5.

3. a kind of power cut off delay under-voltage controller according to claim 1, it is characterized in that: described power supply charge-discharge circuit includes the 5th diode D1, the 6th diode D2, the second resistance R1, the second electrochemical capacitor C5, the negative electrode of described 5th diode D1 and one end of the second resistance R1 are connected, the other end of the second resistance R1 and the positive pole of the second electrochemical capacitor C5 are connected, the minus earth of the second electrochemical capacitor C5；The anode of described 5th diode D1 and the negative electrode of the 6th diode D2 are connected, and the anode of the 6th diode D2 is connected with the positive pole of described second electrochemical capacitor C5, and the negative electrode of the 6th diode D2 is connected with the feeder ear of microprocessor.

4. a kind of power cut off delay under-voltage controller according to claim 1, it is characterized in that: described step-down rectifying circuit includes the 3rd electrochemical capacitor C4 and rectifier bridge, the anode of described 3rd electrochemical capacitor C4 is connected with the outfan of rectifier bridge, the minus earth of described 3rd electrochemical capacitor C4.

5. a kind of power cut off delay under-voltage controller according to claim 1, it is characterised in that: described first switching tube Q2 adopts audion or metal-oxide-semiconductor.

6. a kind of power cut off delay under-voltage controller according to claim 2, it is characterised in that: described second switch pipe Q1 adopts audion or metal-oxide-semiconductor.