CN220042975U - An anti-surge circuit for uninterruptible power supply - Google Patents

Abstract

The utility model relates to the technical field of protection circuits, in particular to an anti-surge circuit of an uninterruptible power supply, which comprises an input unit, a protection unit and a load unit. In the utility model, when the intermittent power supply is started, the trigger module provides power supply voltage for the soft start module, the soft start module limits surge impact current generated when the uninterrupted power supply is started so as to protect normal operation of the uninterrupted power supply and a circuit, and short circuit and open circuit protection of the uninterrupted power supply and the circuit are realized through the short circuit protection module and the open circuit protection module.

Description

An anti-surge circuit for uninterruptible power supply

Technical field

The utility model relates to the technical field of protection circuits, specifically to an anti-surge circuit of an uninterruptible power supply.

Background technique

An uninterruptible power supply is a power supply containing an energy storage device. It is mainly used to provide uninterrupted power supply to some equipment that requires high power supply stability. The surge current refers to the moment when the power is turned on or when an abnormality occurs in the circuit. The peak current or overload current generated under the condition is much larger than the steady-state current, causing damage to the uninterruptible power supply.

For example, CN115313339A relates to a lightning protection and surge protection circuit, which replaces the existing varistor with an inductor of 2-3 microhenries or a milliohm-level resistor. The smaller voltage ensures that the residual voltage of the entire protection circuit is lower, while the normal power frequency voltage increases the protection circuit due to the resistance or inductance after the surge disappears, thereby prompting the discharge tube to arc extinguish and shut down, thereby achieving freewheeling interruption. purpose, and takes up almost no additional space on the PCB board in the application. This anti-surge protection circuit reduces the residual voltage of the protection circuit by replacing it with small impedance components to achieve lightning protection and anti-surge protection. However, it cannot handle the power supply well. The powerful pulse generated at the moment it is just turned on can cause the circuit to burn out.

In order to prevent circuit damage due to surges, an anti-surge circuit for uninterruptible power supply is proposed.

Utility model content

The purpose of this utility model is to provide an anti-surge circuit for an uninterruptible power supply to solve the problems raised in the above background technology.

In order to achieve the above purpose, the present invention provides an anti-surge circuit of an uninterruptible power supply, which includes an input unit, a protection unit and a load unit. The input unit includes a trigger module and a soft start module, and the protection unit includes a short circuit protection module. and a circuit break protection module. The trigger module is connected to the soft start module. The soft start module is connected to the short circuit protection module and the circuit break protection module. The short circuit protection module and the circuit break protection module are connected to the load unit. ;

The trigger module provides power supply voltage to the soft start module. The soft start module is used to limit the surge current and supply power to the load unit through the short circuit protection module and the open circuit protection module.

As a further improvement of this technical solution, the trigger module includes an integrated voltage regulator, a steady-state trigger and a zero-crossing trigger circuit.

As a further improvement of this technical solution, the soft start module includes thyristor SCR, transistors VT1 and VT2,

The thyristor SCR is connected to a resistor R5, the thyristor SCR is connected in parallel with a resistor R4, the resistor R5 is connected to one end of the main winding of the transformer T1, the resistor R4 is connected to the transformer T1, and the other end of the resistor R4 is connected to the diodes D1 and D2;

The base of the transistor VT1 is connected to the capacitor C1 and connected to the resistors R1 and R2. The resistor R1 is connected to the diodes D5 and D6. The diode D5 is connected to the diode D3. The other end of the diode D1 is connected to the trigger module. The diode D6 is connected to the diode D4, the other end of the diode D2 is connected in parallel to the trigger module, the capacitor C1 is connected to the other end of the resistor R2, the other end of the diode D3 is connected in parallel to the other end of the diode D4, the transistor VT1 The electrode is connected to the base of the triode VT2 and connected to the resistor R3. The emitter of the triode VT1 is connected to the other end of the capacitor C1. The capacitor C2 is connected to the emitter of the triode VT2. The base of the triode VT2 is connected to the transformer T1. The other end of the main winding;

One end of the secondary winding of the transformer T1 is connected to the diode D7, the other end of the secondary winding of the transformer T1 is connected to the diode D8 and connected to the capacitor C3, the diode D8 is connected to the inductor L1 and connected to the other end of the diode D7, the capacitor C3 is connected to the The other end of inductor L1.

As a further improvement of this technical solution, the short-circuit protection module includes relay J1,

One end of the relay J1 is connected to the diode D1 and the resistor R6 and is connected to the capacitor C5. The capacitor C5 is connected to the capacitor C3 and the other end of the resistor R6 is connected to the contact J1-1. The other end of the relay J1 is connected to the diode. The other end of VD1 and resistor R7 are connected in parallel to the other end of the capacitor C3, and the resistor R7 contacts point J1-1.

As a further improvement of this technical solution, the short-circuit protection module further includes a light-emitting diode LED1, one end of the light-emitting diode LED1 is connected to the other end of the relay J1, and the other end of the light-emitting diode LED1 is connected to the resistor R7.

Compared with the existing technology, the beneficial effects of this utility model are:

In the anti-surge circuit of the uninterruptible power supply, when the uninterruptible power supply is turned on, the trigger module provides power supply voltage to the soft-start module. The soft-start module limits the surge current generated when the uninterruptible power supply is turned on to protect the uninterruptible power supply and the circuit. It operates normally, and realizes short-circuit and open-circuit protection for uninterruptible power supplies and circuits through short-circuit protection modules and circuit-opening protection modules.

Description of the drawings

Figure 1 is a schematic diagram of the overall structure of the utility model;

Figure 2 is a circuit diagram of the soft start module of the present utility model;

Figure 3 is a circuit diagram of the short circuit protection module of the present invention.

Detailed ways

The technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only part of the embodiments of the present utility model, not all implementations. example. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present utility model.

Example 1

Please refer to Figures 1 to 3. This embodiment provides an anti-surge circuit for an uninterruptible power supply, including an input unit, a protection unit and a load unit. The input unit includes a trigger module and a soft start module, and the protection unit includes short circuit protection. module and circuit break protection module, the trigger module is connected to the soft start module, the soft start module is connected to the short circuit protection module and circuit break protection module, the short circuit protection module and circuit break protection module are connected to the load unit;

The trigger module provides power supply voltage to the soft-start module. The soft-start module is used to limit the surge current and supply power to the load unit through the short-circuit protection module and the open-circuit protection module.

Principle: When the uninterruptible power supply is turned on, the trigger module provides power supply voltage to the soft-start module. The soft-start module limits the surge current generated when the uninterruptible power supply is turned on to protect the normal operation of the uninterruptible power supply and circuit, and through the short-circuit protection module , The open circuit protection module realizes short circuit and open circuit protection for uninterruptible power supplies and circuits.

In order to provide the power supply voltage for the soft-start module, the trigger module includes an integrated voltage regulator, a steady-state trigger and a zero-crossing trigger circuit. The integrated voltage regulator is used to output a stable power supply voltage for the soft-start module. When the power supply voltage crosses zero, it is a zero-crossing trigger. The circuit cuts off the output low level and the steady-state flip-flop works.

The soft start module includes thyristor SCR, triode VT1, VT2,

The thyristor SCR is connected to the resistor R5, and the thyristor SCR is connected in parallel with the resistor R4. The resistor R5 is connected to one end of the main winding of the transformer T1, the resistor R4 is connected to the transformer T1, and the other end of the resistor R4 is connected to the diodes D1 and D2;

The base of transistor VT1 is connected to capacitor C1 and resistors R1 and R2. Resistor R1 is connected to diodes D5 and D6. Diode D5 is connected to diode D3 and the other end of diode D1 in parallel to the trigger module. Diode D6 is connected to diode D4 and the other end of diode D2 in parallel to the trigger module. Module, capacitor C1 is connected to the other end of resistor R2, the other end of diode D3 is connected to the other end of diode D4, the collector of transistor VT1 is connected to the base of transistor VT2 and connected to resistor R3, the emitter of transistor VT1 is connected to the other end of capacitor C1, and the capacitor C2 is connected to the transistor in parallel. VT2 emitter and transistor VT2 base are connected to the other end of the main winding of transformer T1;

One end of the secondary winding of transformer T1 is connected to diode D7, the other end of the secondary winding of transformer T1 is connected to diode D8 and connected to capacitor C3, diode D8 is connected to inductor L1 and the other end of diode D7, and capacitor C3 is connected to the other end of inductor L1.

In this circuit, diodes D5, D6, transistor VT1, resistor 2, and C2 form an instantaneous power failure detection circuit. The selection of time constants R2 and C2 should be slightly larger than half a cycle. When an instantaneous power failure occurs at the input, the detection circuit obtains signal, turn off the drive signal of the power switch transistor VT2, and cut off the gate trigger signal of the thyristor SCR to ensure that the inrush current is prevented when the power is turned back on.

In order to avoid possible short circuit conditions in the load unit, the short circuit protection module includes relay J1,

One end of relay J1 is connected to diode D1, resistor R6 and capacitor C5. Capacitor C5 is connected to capacitor C3 and the other end of resistor R6 and contact J1-1. The other end of relay J1 is connected to the other end of diode VD1 and resistor R7 and the other end of capacitor C3. , Resistor R7 contact point J1-1.

When the circuit is energized, the instantaneous pulse charges the capacitor C5 through the relay J1. The relay J1 is powered and the load unit is powered to work. When a short circuit occurs in the load unit, the working voltage of the relay J1 drops, the relay J1 is released, and the contact J1-1 is opened. When turned on, the load unit is powered off to realize short circuit protection for the circuit.

In order to facilitate knowing the cause of circuit interruption, the short-circuit protection module also includes a light-emitting diode LED1. One end of the light-emitting diode LED1 is connected to the other end of the relay J1, and the other end of the light-emitting diode LED1 is connected to the resistor R7.

When the light-emitting diode LED1 is lit, it is clear that the current circuit is interrupted due to a short circuit of the load unit, which facilitates quick troubleshooting of the cause of the fault.

The anti-surge circuit of an uninterruptible power supply in this embodiment is used in detail. When the uninterruptible power supply is turned on, it supplies power to the trigger module. The integrated voltage regulator is used to output a stable power supply voltage for the soft start module. When the power supply voltage crosses zero, The zero-crossing trigger circuit cuts off the output low level, and the steady-state trigger works to control the soft-start module to limit the surge current generated when the uninterruptible power supply is turned on to protect the normal operation of the uninterruptible power supply and the circuit. When the circuit is powered on, instantaneous The pulse charges the capacitor C5 through the relay J1. The relay J1 is powered and the load unit is powered to work. When the load unit is short-circuited, the working voltage of the relay J1 drops, the relay J1 is released, the contact J1-1 is disconnected, and the load unit is disconnected. electricity to achieve short circuit protection for the circuit.

The basic principles, main features and advantages of the present utility model are shown and described above. Those skilled in the industry should understand that the present utility model is not limited by the above-mentioned embodiments. The above-mentioned embodiments and descriptions are only preferred examples of the present utility model and are not used to limit the present utility model. Without departing from the present utility model, Under the premise of keeping the spirit and scope of the present utility model, there will be various changes and improvements, and these changes and improvements all fall within the scope of the claimed utility model. The protection scope of the present utility model is defined by the appended claims and their equivalents.

Claims (5)

1. An anti-surge circuit of an uninterruptible power supply, which is characterized in that: the device comprises an input unit, a protection unit and a load unit, wherein the input unit comprises a trigger module and a soft start module, the protection unit comprises a short circuit protection module and a circuit breaking protection module, the trigger module is connected with the soft start module, the soft start module is connected with the short circuit protection module and the circuit breaking protection module, and the short circuit protection module and the circuit breaking protection module are connected with the load unit;

the triggering module is used for providing power supply voltage for the soft starting module, and the soft starting module is used for limiting surge impact current and supplying power for the load unit through the short circuit protection module and the circuit breaking protection module.

2. The anti-surge circuit of an uninterruptible power supply of claim 1, wherein: the trigger module comprises an integrated voltage stabilizer, a steady-state trigger and a zero-crossing trigger circuit.

3. The anti-surge circuit of an uninterruptible power supply of claim 1, wherein: the soft start module comprises thyristors SCR, triodes VT1 and VT2,

the thyristor SCR is connected with a resistor R5 in parallel, the resistor R5 is connected with one end of a main winding of the transformer T1, the resistor R4 is connected with the transformer T1, and the other end of the resistor R4 is connected with diodes D1 and D2;

the base electrode of the triode VT1 is connected with a capacitor C1 and connected with resistors R1 and R2 in parallel, the resistor R1 is connected with a diode D5 and D6, the diode D5 is connected with a diode D3, the other end of the diode D1 is connected with the trigger module in parallel, the diode D6 is connected with a diode D4, the other end of the diode D2 is connected with the trigger module in parallel, the capacitor C1 is connected with the other end of the resistor R2, the other end of the diode D3 is connected with the other end of the diode D4 in parallel, the collector electrode of the triode VT1 is connected with the base electrode of the triode VT2 in parallel with the resistor R3, the emitter electrode of the triode VT1 is connected with the other end of the capacitor C1 and connected with the emitter electrode of the triode VT2 in parallel, and the base electrode of the triode VT2 is connected with the other end of the main winding of the transformer T1;

one end of the secondary winding of the transformer T1 is connected with a diode D7, the other end of the secondary winding of the transformer T1 is connected with a diode D8 in parallel, the diode D8 is connected with an inductor L1 in parallel and connected with the other end of the diode D7, and the capacitor C3 is connected with the other end of the inductor L1.

4. The anti-surge circuit of an uninterruptible power supply of claim 3, wherein: the short-circuit protection module comprises a relay J1,

one end of the relay J1 is connected with the diode D1 and the resistor R6 in parallel connection with the capacitor C5, the capacitor C5 is connected with the capacitor C3 in parallel connection with the other end of the resistor R6 and the contact J1-1, the other end of the relay J1 is connected with the other end of the diode VD1 and the resistor R7 in parallel connection with the other end of the capacitor C3, and the resistor R7 is connected with the contact J1-1.

5. The anti-surge circuit of uninterruptible power supply of claim 4, wherein: the short-circuit protection module further comprises a Light Emitting Diode (LED) 1, one end of the LED1 is connected with the other end of the relay J1, and the other end of the LED1 is connected with the resistor R7.