CN221329184U - LED emergency power supply circuit - Google Patents

Abstract

The utility model discloses an LED emergency power supply circuit, which comprises two isolating switches, a DC constant voltage circuit, a DC constant current circuit, a logic control circuit, a switch circuit, a unidirectional conduction circuit and a storage battery, wherein when the LED emergency power supply of the LED emergency power supply circuit and an external LED lighting lamp of the existing driving power supply are adopted to form the LED lighting lamp with an emergency lighting function, the DC constant voltage circuit provides charging voltage for the storage battery by utilizing direct current voltage output between a positive output end and a negative output end of the LED driving power supply, and because the existing DC constant voltage circuit takes electricity from the LED constant current output end, no additional conduction and radiation related circuits and safety certification are required; the advantages are low cost and cost competitive advantage.

Description

LED emergency power supply circuit

Technical Field

The utility model relates to an emergency power supply circuit, in particular to an LED emergency power supply circuit.

Background

As shown in fig. 1, a type of LED lighting fixture with an external driving power supply, which is widely used at present, includes an LED driving power supply and an LED fixture body. The LED driving power supply is provided with a live wire input end, a zero line input end, a positive output end and a negative output end, the LED lamp main body is provided with a positive input end and a negative input end, and because the LED driving power supply is positioned outside the LED lamp main body, the positive input end of the LED lamp main body is connected with the positive output end of the LED driving power supply through a wire, and the negative input end of the LED lamp main body is also connected with the negative output end of the LED driving power supply through a wire. The LED driving power supply is used for converting the mains voltage connected between the live wire input end and the zero line input end into corresponding direct current to be output between the positive output end and the negative output end of the direct current, and supplying power to the LED lamp main body so as to drive the LED lamp main body to emit light. When the LED driving power supply is connected between the live wire input end and the zero line input end, direct current is output between the positive output end and the negative output end of the LED driving power supply, and the LED driving power supply drives the LED lamp main body to emit light, if the direct current output between the positive output end and the negative output end of the LED driving power supply is smaller than a preset current threshold value, the voltage output between the positive output end and the negative output end of the LED driving power supply is equal to the preset threshold voltage.

When the LED illumination lamp with the external driving power supply is in actual use, the zero line input end of the LED driving power supply is connected with the zero line of the commercial power, and the live wire input end of the LED driving power supply is connected with the live wire of the commercial power through a switch. When the switch is closed, mains voltage is connected between the live wire input end and the zero line input end of the LED driving power supply, and the LED driving power supply converts the connected mains voltage into corresponding direct current and outputs the direct current between the positive output end and the negative output end of the direct current, so that the LED lamp main body is driven to emit light. When the switch is disconnected, the LED driving power supply is disconnected with the mains supply, the voltage between the live wire input end and the zero line input end of the LED driving power supply is zero, the direct current output between the positive output end and the negative output end of the LED driving power supply is zero, and the LED lamp main body does not emit light.

At present, an LED emergency power supply can be quickly and conveniently connected and combined with an LED illumination lamp with the external driving power supply to form the LED illumination lamp with an emergency illumination function, so that the requirement of emergency illumination is met. As shown in figure 2, the LED emergency power supply is provided with a first live wire access end, a second live wire access end, a zero wire access end, a positive output end, a negative output end, a live wire output end, a positive input end and a negative input end, in the LED lighting lamp with the emergency lighting function, the zero wire input end of the LED driving power supply is connected with the zero wire access end of the LED emergency power supply, the live wire input end of the LED driving power supply is connected with the live wire output end of the LED emergency power supply, the positive output end and the negative output end of the LED driving power supply are not connected with the positive input end and the negative input end of the LED lamp main body through wires, but the positive output end of the LED driving power supply is connected with the positive input end of the LED emergency power supply, The negative output end of the LED driving power supply is connected with the negative input end of the LED emergency power supply, the positive output end of the LED emergency power supply is connected with the positive input end of the LED lamp main body through a wire, and the negative output end of the LED emergency power supply is connected with the negative input end of the LED lamp main body through a wire. When the LED illumination lamp with the emergency illumination function is in actual use, the first live wire access end of the LED emergency power supply is directly connected with the live wire of the commercial power, the second live wire access end of the LED emergency power supply is connected with the live wire of the commercial power through a switch, and the zero wire access end of the LED emergency power supply is connected with the zero wire of the commercial power. When the mains voltage is normal, the mains voltage is connected between a first live wire access end and a zero line access end of the LED emergency power supply, the LED emergency power supply converts the connected mains voltage into direct current voltage to charge a storage battery in the LED emergency power supply, and the charging is automatically stopped after the storage battery is fully charged; meanwhile, if the switch is closed at this time, the mains voltage is also connected between the second live wire access end and the zero wire access end of the LED emergency power supply, and the mains voltage is output through the live wire output end and the zero wire access end of the LED emergency power supply, at this time, the mains voltage is also connected between the live wire input end and the zero wire input end of the LED driving power supply, the LED driving power supply converts the connected mains voltage into corresponding direct current, the direct current is output between the positive output end and the negative output end of the LED driving power supply, the LED emergency power supply is connected into the direct current output between the positive output end and the negative output end of the LED driving power supply through the positive input end and the negative input end of the LED emergency power supply, and the corresponding direct current is output between the positive output end and the negative output end of the LED driving power supply, Driving the LED lamp body to emit light; If the switch is disconnected at this time, no mains voltage is connected between the second live wire access end and the zero line access end of the LED emergency power supply, the voltage between the live wire output end and the zero line access end is zero, the voltage between the live wire input end and the zero line input end of the LED driving power supply is also zero, the direct current output between the positive output end and the negative output end of the LED driving power supply is zero, the direct current output between the positive output end and the negative output end of the LED emergency power supply is also zero, and the LED lamp body does not emit light. When the mains voltage is abnormal, the LED emergency power supply detects that the mains voltage is abnormal, the electric energy stored in the storage battery is converted into direct current to be output between the positive output end and the negative output end of the direct current, the LED lamp main body is driven to emit light, meanwhile, the voltage output between the live wire output end and the zero line access end of the LED emergency power supply is zero, the voltage accessed between the live wire input end and the zero line input end of the LED driving power supply is also zero, the direct current output between the positive output end and the negative output end of the LED driving power supply is also zero, and the LED driving power supply does not work.

The LED lighting lamp with the emergency lighting function can be directly and quickly formed by utilizing the existing LED emergency power supply and the existing LED lighting lamp with the external driving power supply, and is widely applied to places such as aisles, parking lots and the like which need to keep lighting when the mains supply voltage of a power grid is abnormal. However, the existing LED emergency power supply generally uses a charging circuit for converting the mains voltage into a direct current voltage to charge a storage battery inside the LED emergency power supply. Because the charging circuit directly obtains voltage from the mains supply, the charging circuit needs a conduction and radiation related circuit besides an AC-DC constant current conversion circuit with higher cost, so that the LED emergency power supply meets the requirements of related countries or regions on conduction and radiation indexes, and the factors lead to higher cost of the product and lack of cost competitive advantages.

Disclosure of Invention

The utility model aims to solve the technical problem of providing an LED emergency power supply circuit with low cost and cost competitive advantage.

The technical scheme adopted for solving the technical problems is as follows: an LED emergency power supply circuit comprises a first live wire access end, a second live wire access end, a zero wire access end, a positive output end, a negative output end, a live wire output end, a positive input end and a negative input end, wherein the LED emergency power supply circuit comprises a storage battery, the storage battery is provided with a positive electrode and a negative electrode, the LED emergency power supply circuit also comprises two isolating switches, a DC constant voltage circuit, a DC constant current circuit, a switch circuit, a logic control circuit and a unidirectional conduction circuit, each isolating switch is provided with a first input end, a second input end, a positive output end and a negative output end, When the first input end and the second input end are connected with the mains voltage, the positive output end and the negative output end of the power supply are conducted, and when the first input end and the second input end are not connected with the mains voltage, the positive output end and the negative output end of the power supply are cut off; The two isolating switches are respectively called a first isolating switch and a second isolating switch; the DC constant voltage circuit is used for converting direct current voltage connected between the input end and the negative electrode into corresponding direct current voltage to be output between the output end and the negative electrode, the DC constant voltage circuit is provided with the input end, the negative electrode, the output end and a control end, when the control end of the DC constant current circuit is connected with a high level, the voltage connected between the input end and the negative electrode of the DC constant voltage circuit is converted into direct current to be output between the output end and the negative electrode, and when the control end of the DC constant current circuit is connected with a low level, the DC constant current circuit stops working, and the output current between the output end and the negative electrode of the DC constant current circuit is 0; The unidirectional conduction circuit is provided with an anode and a cathode, and the conduction current direction is from the anode to the cathode; the switch circuit is provided with a first connecting end, a second connecting end and a control end, when the control end is at a high level, the first connecting end and the second connecting end are conducted, and when the control end is at a low level, the first connecting end and the second connecting end are cut off; the logic control circuit is provided with an anode, a cathode, a first control end, a second control end and an output end, when the first control end of the logic control circuit is at a low level, if the second control end of the logic control circuit is connected with a positive voltage, the output end of the logic control circuit outputs a high level, if the second control end of the logic control circuit is not connected with the positive voltage, the output end of the logic control circuit outputs a low level, and when the first control end of the logic control circuit is at a high level, no matter whether the second control end of the logic control circuit is connected with the positive voltage or not, the output end of the logic control circuit outputs a high level; The first input end of the first isolating switch is a first live wire access end of the LED emergency power supply circuit and is a live wire output end of the LED emergency power supply circuit; the first input end of the second isolating switch is a second live wire access end of the LED emergency power supply circuit, the second input end of the first isolating switch is connected with the second input end of the second isolating switch, the connection end of the second isolating switch is a zero line access end of the LED emergency power supply circuit, the positive output end of the first isolating switch is respectively connected with the first control end of the logic control circuit and the control end of the DC constant current circuit, the negative output end of the second isolating switch is connected with the second control end of the logic control circuit, the positive output end of the second isolating switch, the positive electrode of the logic control circuit, The output end of the DC constant voltage circuit, the input end of the DC constant current circuit and the positive electrode of the storage battery are connected, the output end of the logic control circuit is connected with the control end of the switch circuit, the input end of the DC constant voltage circuit is connected with the positive electrode of the unidirectional conduction circuit, the connection end of the DC constant voltage circuit is the positive input end of the LED emergency power circuit, the output end of the DC constant current circuit is connected with the negative electrode of the unidirectional conduction circuit, the connection end of the DC constant current circuit is the positive output end of the LED emergency power circuit, and the first connection end of the switch circuit is the negative output end of the LED emergency power circuit; The negative electrode of the DC constant voltage circuit, the negative electrode of the DC constant current circuit, the negative output end of the first isolating switch, the second connecting end of the switch circuit and the negative electrode of the storage battery are connected, and the connecting end of the switch circuit is the negative input end of the LED emergency power supply circuit.

The first isolating switch comprises a first capacitor, a second capacitor, a first resistor, a second resistor, a first bridge stack, a first diode and a first optocoupler, wherein the second capacitor is an electrolytic capacitor, the first diode is a zener diode, the first bridge stack is provided with two alternating current input ends, a positive output end and a negative output end, the first optocoupler is provided with an anode, a cathode, a collector and an emitter, one end of the first resistor is connected with one end of the first capacitor, the connecting end of the first resistor is the first input end of the first isolating switch, the other end of the first resistor, the other end of the first capacitor and the first alternating current input end of the first bridge stack are connected, the other alternating current input end of the first bridge stack is the second input end of the first isolating switch, the positive output end of the first bridge stack, the negative electrode of the second diode and the first capacitor are connected with the positive output end of the first diode, the positive output end of the first diode and the first diode are connected with the negative output end of the first optocoupler of the first diode; the second isolating switch comprises a third capacitor, a fourth capacitor, a third resistor, a fourth resistor, a second bridge stack, a second diode and a second optocoupler, wherein the fourth capacitor is an electrolytic capacitor, the second diode is a voltage stabilizing diode, the second bridge stack is provided with two alternating current input ends, a positive output end and a negative output end, the second optocoupler is provided with an anode, a cathode, a collector and an emitter, one end of the third resistor is connected with one end of the third capacitor, the connecting end of the second capacitor is a first input end of the second isolating switch, the other end of the third resistor, the other end of the third capacitor, the first alternating current input end of the second bridge stack, the other alternating current input end of the second bridge stack, the positive output end of the second bridge stack, the negative electrode of the fourth capacitor, the positive electrode of the fourth resistor, the negative output end of the fourth resistor, the positive output end of the fourth resistor, the second optocoupler and the negative output end of the second bridge are connected.

The logic control circuit comprises a fifth resistor, a sixth resistor, a third diode and a fourth diode, wherein the third diode and the fourth diode are rectifier diodes, one end of the fifth resistor is the positive electrode of the logic control circuit, the other end of the fifth resistor is connected with the positive electrode of the fourth diode, the connecting end of the fifth resistor is the first control end of the logic control circuit, the positive electrode of the third diode is the second control end of the logic control circuit, the negative electrode of the third diode, the negative electrode of the fourth diode and one end of the sixth resistor are connected, the connecting end of the fourth diode is the output end of the logic control circuit, and the other end of the sixth resistor is the negative electrode of the logic control circuit. The logic control circuit is built by utilizing discrete components and has the advantage of low cost.

The switching circuit comprises a first MOS tube, the gate of the first MOS tube is the control end of the switching circuit, the drain electrode of the first MOS tube is the first connecting end of the switching circuit, and the source electrode of the first MOS tube is the second connecting end of the switching circuit.

The unidirectional conduction circuit is realized by adopting a Schottky rectifier diode, the positive electrode of the Schottky rectifier diode is the positive electrode of the unidirectional conduction circuit, and the negative electrode of the Schottky rectifier diode is the negative electrode of the unidirectional conduction circuit.

The DC constant voltage circuit adopts a DC-DC step-down constant voltage circuit in the prior art, and the output voltage and the maximum output current of the DC-DC step-down constant voltage circuit can be preset.

The DC constant current circuit adopts a DC-DC boost constant current circuit in the prior art, and the output current of the DC-DC boost constant current circuit can be preset.

Compared with the prior art, the LED emergency power supply circuit has the advantages that the LED emergency power supply circuit is formed by the two isolating switches, the DC constant voltage circuit, the DC constant current circuit, the logic control circuit, the switch circuit, the unidirectional conduction circuit and the storage battery, when the LED emergency power supply realized by adopting the LED emergency power supply circuit is connected and combined with the existing LED lighting lamp with the external driving power supply to form the LED lighting lamp with the emergency lighting function, the zero line input end of the LED driving power supply is connected with the zero line access end of the LED emergency power supply circuit, the live line input end of the LED driving power supply is connected with the live line output end of the LED emergency power supply circuit, The positive output end and the negative output end of the LED driving power supply are not connected with the positive input end and the negative input end of the LED lamp main body through wires, but the positive output end of the LED driving power supply is connected with the positive input end of the LED emergency power supply circuit, the negative output end of the LED driving power supply is connected with the negative input end of the LED emergency power supply circuit, the positive output end of the LED emergency power supply circuit is connected with the positive input end of the LED lamp main body through wires, and the negative output end of the LED emergency power supply circuit is connected with the negative input end of the LED lamp main body through wires; When the LED illumination lamp with the emergency illumination function is in actual use, a first live wire access end (a live wire output end) of the LED emergency power supply circuit is directly connected with a live wire of a commercial power, a second live wire access end of the LED emergency power supply circuit is connected with the live wire of the commercial power through a switch S1, and a zero wire access end of the LED emergency power supply circuit is connected with a zero wire of the commercial power; When the mains voltage is normal, the normal mains voltage is connected between the live wire input end and the zero line input end of the LED driving power supply, the positive output end and the negative output end of the first isolating switch are conducted, the positive output end outputs a low level, the DC constant current circuit is set in a non-working state, the current output by the output end of the DC constant current circuit is 0, meanwhile, the LED driving power supply converts the mains voltage, a corresponding direct current or threshold voltage preset in the LED driving power supply is output between the positive output end and the negative output end according to a load connection state, if the switch S1 is in a closed state, The utility voltage is connected between the first input end and the second input end of the second isolating switch, the positive output end and the negative output end of the second isolating switch are communicated, the output end of the logic control circuit outputs a high level, the first connection end and the second connection end of the switching circuit are communicated, the LED driving power supply drives the LED lamp main body to emit light through the unidirectional communication circuit, meanwhile, the direct current voltage which is output between the positive output end and the negative output end of the LED driving power supply and is related to the working voltage of the LED lamp main body is connected between the input end and the negative electrode of the DC constant voltage circuit, the DC constant voltage circuit converts the direct current voltage into the direct current voltage which can charge the storage battery and is output between the output end and the negative electrode of the storage battery, If the storage battery does not reach a full-charge state, the direct current voltage output between the output end and the negative electrode of the DC constant voltage circuit charges the storage battery, the current output between the output end and the negative electrode of the DC constant voltage circuit is not zero, at the moment, a small part of direct current output between the positive output end and the negative output end of the LED driving power supply is used for charging the storage battery through the DC constant voltage circuit, and most of direct current is used for driving the LED lamp main body to emit light after passing through the unidirectional conduction circuit; If the storage battery is in a full-charge state, the storage battery stops charging, the current output between the output end and the negative electrode of the DC constant voltage circuit is zero, and all direct current output between the positive output end and the negative output end of the LED driving power supply is used for driving the LED lamp main body to emit light through the unidirectional conduction circuit; If at this time the switch S1 is in the off state, no mains voltage is connected between the first input end and the second input end of the second isolating switch, the positive output end and the negative output end of the second isolating switch are cut off, the output end of the logic control circuit outputs a low level, the first connection end and the second connection end of the switching circuit are cut off, a current loop cannot be formed between the positive output end and the negative output end of the LED driving power supply, the output current is zero, the output voltage is equal to the voltage threshold preset in the LED driving power supply, at this time, the LED lamp body does not emit light, at the same time, the direct current voltage with the voltage threshold is connected between the input end and the negative electrode of the DC constant voltage circuit, The DC constant voltage circuit converts the direct current voltage into a direct current voltage capable of charging the storage battery and outputs the direct current voltage between the output end and the negative electrode of the direct current constant voltage circuit, if the storage battery does not reach a full-charge state, the direct current voltage output between the output end and the negative electrode of the direct current constant voltage circuit charges the storage battery, and if the storage battery is in the full-charge state, the storage battery stops charging, and the current output between the output end and the negative electrode of the direct current constant voltage circuit is zero; When the mains voltage is abnormal, the mains voltage cannot be connected between the live wire input end and the zero line input end of the LED driving power supply, the LED driving power supply enters a non-working state, no current output nor voltage output exists between the positive output end and the negative output end of the LED driving power supply, no matter whether the switch S1 is in a closed state or an open state, the first isolating switch cannot be connected with the mains voltage, the positive output end and the negative output end of the first isolating switch are cut off, the positive output end of the first isolating switch is in a high level, the output end of the logic control circuit outputs a high level, the first connecting end and the second connecting end of the switching circuit are conducted, and meanwhile, the control end of the DC constant current circuit is connected with the high level for working, Converting the voltage between the anode and the cathode of the storage battery into constant current and outputting the constant current between the output end and the cathode of the storage battery to drive the LED lamp main body to emit light, wherein the unidirectional conduction circuit is in a reverse cut-off state at the moment, and the DC constant voltage circuit is in a non-working state; Therefore, the LED emergency power supply circuit utilizes the direct current voltage output between the positive output end and the negative output end of the LED driving power supply to provide charging voltage for the storage battery through the DC constant voltage circuit with lower cost in DC-DC conversion, meanwhile, the traditional DC constant voltage circuit obtains voltage from the output end of the LED constant current power supply, so that an additional conduction and radiation related circuit and safety certification are not required, the utility model replaces the AC-DC constant current conversion circuit with higher cost and the conduction and radiation related circuit with the DC constant voltage circuit with lower cost to realize the charging circuit for charging the storage battery, thereby reducing the cost of the LED emergency power supply, And the cost competitive advantage of the LED emergency power supply is improved.

Drawings

FIG. 1 is a block diagram of an LED lighting fixture with an external driving power supply in the prior art;

FIG. 2 is a block diagram of an LED lighting fixture with emergency lighting function utilizing an existing LED emergency power supply and an existing LED lighting fixture with an external drive power supply;

FIG. 3 is a block diagram of an LED lighting fixture with emergency lighting function utilizing the LED emergency power supply circuit of the present utility model and an external LED lighting fixture of a conventional driving power supply;

fig. 4 is a circuit diagram of two isolation switches, logic control circuits and switching circuits of the LED emergency power supply circuit of the present utility model.

Detailed Description

The utility model is described in further detail below with reference to the embodiments of the drawings.

Embodiment one: as shown in fig. 3, an LED emergency power supply circuit having a first live wire access terminal, a second live wire access terminal, a neutral wire access terminal, a positive output terminal, a negative output terminal, a live wire output terminal, a positive input terminal, and a negative input terminal, the LED emergency power supply circuit comprising a storage battery having a positive electrode and a negative electrode, the LED emergency power supply circuit further comprising two isolation switches, a DC constant voltage circuit, a DC constant current circuit, a switching circuit, a logic control circuit, and a unidirectional conduction circuit, each isolation switch having a first input terminal, a second input terminal, a positive output terminal, and a negative output terminal, when an electric supply voltage is applied between the first input terminal and the second input terminal thereof, the positive output end and the negative output end of the power supply are conducted, and when the mains voltage is not connected between the first input end and the second input end of the power supply, the positive output end and the negative output end of the power supply are cut off; The two isolating switches are respectively called a first isolating switch and a second isolating switch; the DC constant voltage circuit is used for converting direct current voltage connected between the input end and the negative electrode into corresponding direct current voltage to be output between the output end and the negative electrode, the DC constant current circuit is provided with the input end, the negative electrode, the output end and a control end, when the control end of the DC constant current circuit is connected with a high level, the voltage connected between the input end and the negative electrode of the DC constant current circuit is converted into direct current to be output between the output end and the negative electrode, and when the control end of the DC constant current circuit is connected with a low level, the DC constant current circuit stops working, and the output current between the output end and the negative electrode of the DC constant current circuit is 0; The unidirectional conduction circuit is provided with a positive electrode and a negative electrode, and the conduction current direction is from the positive electrode to the negative electrode; the switch circuit is provided with a first connecting end, a second connecting end and a control end, when the control end is at a high level, the first connecting end and the second connecting end are conducted, and when the control end is at a low level, the first connecting end and the second connecting end are cut off; the logic control circuit is provided with an anode, a cathode, a first control end, a second control end and an output end, when the first control end of the logic control circuit is at a low level, if the second control end of the logic control circuit is connected with a positive voltage, the output end of the logic control circuit outputs a high level, if the second control end of the logic control circuit is not connected with the positive voltage, the output end of the logic control circuit outputs a low level, and when the first control end of the logic control circuit is at a high level, no matter whether the second control end of the logic control circuit is connected with the positive voltage, the output end of the logic control circuit outputs a high level; The first input end of the first isolating switch is a first live wire access end of the LED emergency power supply circuit and a live wire output end of the LED emergency power supply circuit; The first input end of the second isolating switch is a second live wire access end of the LED emergency power supply circuit, the second input end of the first isolating switch is connected with the second input end of the second isolating switch, the connection end of the second isolating switch is a zero line access end of the LED emergency power supply circuit, the positive output end of the first isolating switch is respectively connected with the first control end of the logic control circuit and the control end of the DC constant current circuit, the negative output end of the second isolating switch is connected with the second control end of the logic control circuit, the positive output end of the second isolating switch, the positive electrode of the logic control circuit, the output end of the DC constant voltage circuit, the input end of the DC constant current circuit and the positive electrode of the storage battery are connected, The output end of the logic control circuit is connected with the control end of the switch circuit, the input end of the DC constant voltage circuit is connected with the positive electrode of the unidirectional conduction circuit, the connection end of the DC constant voltage circuit is the positive input end of the LED emergency power circuit, the output end of the DC constant current circuit is connected with the negative electrode of the unidirectional conduction circuit, the connection end of the DC constant current circuit is the positive output end of the LED emergency power circuit, and the first connection end of the switch circuit is the negative output end of the LED emergency power circuit; The negative electrode of the DC constant voltage circuit, the negative electrode of the DC constant current circuit, the negative output end of the first isolating switch, the second connecting end of the switch circuit and the negative electrode of the storage battery are connected, and the connecting end of the switch circuit is the negative input end of the LED emergency power supply circuit.

In this embodiment, the two isolating switches, the DC constant voltage circuit, the DC constant current circuit, the logic control circuit, the switching circuit and the unidirectional conduction circuit may be implemented by using mature products in the technical field.

When the LED emergency power supply realized by the LED emergency power supply circuit is connected and combined with an existing LED lighting lamp with an external driving power supply to form the LED lighting lamp with an emergency lighting function, a zero line input end of the LED driving power supply is connected with a zero line access end of the LED emergency power supply circuit, a live wire input end of the LED driving power supply is connected with a live wire output end of the LED emergency power supply circuit, a positive output end and a negative output end of the LED driving power supply are not connected with a positive input end and a negative input end of the LED lamp main body any more through wires, but a positive output end of the LED driving power supply is connected with a positive input end of the LED emergency power supply circuit, a positive output end of the LED emergency power supply circuit is connected with a positive input end of the LED lamp main body through wires, and a negative output end of the LED emergency power supply circuit is connected with a negative input end of the LED lamp main body through wires; when the LED illumination lamp with the emergency illumination function is in actual use, the first live wire access end (live wire output end) of the LED emergency power supply circuit is directly connected with the live wire of the mains supply, the second live wire access end of the LED emergency power supply circuit is connected with the live wire of the mains supply through the switch S1, and the zero wire access end of the LED emergency power supply circuit is connected with the zero wire of the mains supply.

When the mains voltage is normal, the normal mains voltage is connected between the live wire input end and the zero line input end of the LED driving power supply, the positive output end and the negative output end of the first isolating switch are conducted, the positive output end outputs a low level, the DC constant current circuit is set in a non-working state, the current output by the output end of the DC constant current circuit is 0, meanwhile, the LED driving power supply converts the mains voltage, a corresponding direct current or threshold voltage preset in the LED driving power supply is output between the positive output end and the negative output end according to a load connection state, if the switch S1 is in a closed state, The utility voltage is connected between the first input end and the second input end of the second isolating switch, the positive output end and the negative output end of the second isolating switch are communicated, the output end of the logic control circuit outputs a high level, the first connection end and the second connection end of the switching circuit are communicated, the LED driving power supply drives the LED lamp main body to emit light through the unidirectional communication circuit, meanwhile, the direct current voltage which is output between the positive output end and the negative output end of the LED driving power supply and is related to the working voltage of the LED lamp main body is connected between the input end and the negative electrode of the DC constant voltage circuit, the DC constant voltage circuit converts the direct current voltage into the direct current voltage which can charge the storage battery and is output between the output end and the negative electrode of the storage battery, if the storage battery does not reach a full-charge state, the direct current voltage output between the output end and the negative electrode of the DC constant voltage circuit charges the storage battery, the current output between the output end and the negative electrode of the DC constant voltage circuit is not zero, and at the moment, a small part of direct current output between the positive output end and the negative output end of the LED driving power supply is used for charging the storage battery through the DC constant voltage circuit, and most of direct current is used for driving the LED lamp main body to emit light after passing through the unidirectional conduction circuit. If the storage battery is in a full-charge state, the storage battery stops charging, the current output between the output end and the negative electrode of the DC constant voltage circuit is zero, and all direct current output between the positive output end and the negative output end of the LED driving power supply is used for driving the LED lamp main body to emit light through the unidirectional conduction circuit; If at this time the switch S1 is in the off state, no mains voltage is connected between the first input end and the second input end of the second isolating switch, the positive output end and the negative output end of the second isolating switch are cut off, the output end of the logic control circuit outputs a low level, the first connection end and the second connection end of the switching circuit are cut off, a current loop cannot be formed between the positive output end and the negative output end of the LED driving power supply, the output current is zero, the output voltage is equal to the voltage threshold preset in the LED driving power supply, at this time, the LED lamp body does not emit light, at the same time, the direct current voltage with the voltage threshold is connected between the input end and the negative electrode of the DC constant voltage circuit, the DC constant voltage circuit converts the direct current voltage into a direct current voltage capable of charging the storage battery and outputs the direct current voltage between an output terminal and a negative electrode of the direct current constant voltage circuit, if the storage battery does not reach a full-charge state, the direct current voltage output between the output terminal and the negative electrode of the direct current constant voltage circuit charges the storage battery, and if the storage battery is in the full-charge state, the storage battery stops charging, and the magnitude of the current output between the output terminal and the negative electrode of the direct current constant voltage circuit is zero.

When the mains voltage is abnormal, in the LED lighting lamp with the emergency lighting function, the mains voltage cannot be connected between the live wire input end and the zero wire input end of the LED driving power supply, the LED driving power supply enters a non-working state, no current output nor voltage output exists between the positive output end and the negative output end of the LED driving power supply, no matter whether the switch S1 is in a closed state or an open state, the first isolating switch cannot be connected with the mains voltage, the positive output end and the negative output end of the first isolating switch are cut off, the positive output end of the first isolating switch is high level, the output end of the logic control circuit outputs high level, the first connecting end and the second connecting end of the switching circuit are conducted, meanwhile, the control end of the DC constant current circuit is connected with the high level to work, the voltage between the positive electrode and the negative electrode of the storage battery is converted into constant current, the constant current is output between the output end and the negative electrode, the main body of the LED lighting lamp is driven, the unidirectional conducting circuit is in a reverse cut-off state, and the DC constant voltage circuit is in the non-working state.

The LED emergency power supply circuit of the embodiment utilizes the direct current voltage output between the positive output end and the negative output end of the LED driving power supply through the DC constant voltage circuit with lower cost for providing charging voltage for the storage battery, meanwhile, the existing DC constant voltage circuit can adopt safe and extremely low voltage to meet corresponding safety certification requirements, so that a conduction and radiation related circuit and safety certification do not need to be additionally arranged, and the charging circuit for charging the storage battery is realized by adopting the DC constant voltage circuit with lower cost to replace an AC-DC constant current conversion circuit with higher cost and a conduction and radiation related circuit, thereby reducing the cost of the LED emergency power supply and improving the cost competitive advantage of the LED emergency power supply.

Embodiment two: this embodiment is substantially the same as embodiment one, except that: as shown in fig. 4, in this embodiment, the first isolation switch includes a first capacitor C1, a second capacitor C2, a first resistor R1, a second resistor R2, a first bridge Db1, a first diode D1, and a first optocoupler U1, where the second capacitor C2 is an electrolytic capacitor, the first diode D1 is a zener diode, the first bridge Db1 has two ac input ends, a positive output end, and a negative output end, the first optocoupler U1 has an anode, a cathode, a collector, and an emitter, one end of the first resistor R1 is connected to one end of the first capacitor C1, the connection end is a first input end of the first isolation switch, the other end of the first resistor R1, the other end of the first capacitor C1 is connected to one ac input end of the first bridge Db1, the other ac input end of the first bridge Db1 is a second input end of the first isolation switch, the output end of the first bridge Db1, the negative electrode of the second capacitor C2 is connected to the positive output end of the first diode D1, the positive output end of the second capacitor C2 is connected to the first optocoupler U1, and the negative end of the first diode D1 is connected to the positive output end of the first diode U1; the second isolating switch comprises a third capacitor C3, a fourth capacitor C4, a third resistor R3, a fourth resistor R4, a second bridge Db2, a second diode D2 and a second optocoupler U2, wherein the fourth capacitor C4 is an electrolytic capacitor, the second diode D2 is a voltage-stabilizing diode, the second bridge Db2 is provided with two alternating current input ends, a positive output end and a negative output end, the second optocoupler U2 is provided with an anode, a cathode, a collector and an emitter, one end of the third resistor R3 is connected with one end of the third capacitor C3, the connecting end of the third resistor R3 is a first input end of the second isolating switch, the other end of the third resistor C3 is connected with one alternating current input end of the second bridge Db2, the other alternating current input end of the second bridge Db2 is a second input end of the second isolating switch, the positive output end of the second bridge Db2, the positive electrode of the fourth capacitor C4 is connected with the positive output end of the fourth resistor R4 and the negative output end of the fourth resistor R4 of the second optocoupler U2, and the positive output end of the fourth resistor D2 of the fourth resistor R4 is connected with the positive output end of the second optocoupler U2 of the second bridge D2.

Embodiment III: this embodiment is basically the same as the second embodiment, except that: as shown in fig. 4, in this embodiment, the logic control circuit includes a fifth resistor R5, a sixth resistor R6, a third diode D3, and a fourth diode D4, where the third diode D3 and the fourth diode D4 are rectifier diodes, one end of the fifth resistor R5 is an anode of the logic control circuit, the other end of the fifth resistor R5 is connected to an anode of the fourth diode D4, and a connection end of the fifth resistor R5 is a first control end of the logic control circuit, an anode of the third diode D3 is a second control end of the logic control circuit, a cathode of the third diode D3, a cathode of the fourth diode D4, and one end of the sixth resistor R6 are connected, a connection end of the third diode D3 is an output end of the logic control circuit, and another end of the sixth resistor R6 is a cathode of the logic control circuit.

In this embodiment, the switching circuit includes a first MOS transistor Q1, a gate of the first MOS transistor Q1 is a control end of the switching circuit, a drain of the first MOS transistor Q1 is a first connection end of the switching circuit, and a source of the first MOS transistor Q1 is a second connection end of the switching circuit.

In this embodiment, the logic control circuit is built by using discrete components, and has the advantage of low cost while realizing logic control.

Embodiment four: this embodiment is substantially the same as embodiment three except that: in this embodiment, the unidirectional conduction circuit is implemented by using a schottky rectifier diode, the positive electrode of the schottky rectifier diode is the positive electrode of the unidirectional conduction circuit, and the negative electrode of the schottky rectifier diode is the negative electrode of the unidirectional conduction circuit. The DC constant voltage circuit adopts a DC-DC step-down constant voltage circuit in the prior art, and the output voltage and the maximum output current of the DC-DC step-down constant voltage circuit can be preset. The DC constant current circuit adopts a DC-DC boost constant current circuit in the prior art, and the output current of the DC-DC boost constant current circuit can be preset.

Claims (7)

1. The LED emergency power supply circuit comprises a first live wire access end, a second live wire access end, a zero line access end, a positive output end, a negative output end, a live wire output end, a positive input end and a negative input end, and the LED emergency power supply circuit comprises a storage battery which is provided with a positive electrode and a negative electrode, and is characterized by also comprising two isolating switches, a DC constant voltage circuit, a DC constant current circuit, a switching circuit, a logic control circuit and a unidirectional conduction circuit, wherein each isolating switch is provided with a first input end, a second input end, a positive output end and a negative output end, and when the first input end and the second input end are connected with a mains voltage, the positive output end and the negative output end of the power supply are conducted, and when the mains voltage is not connected between the first input end and the second input end of the power supply, the positive output end and the negative output end of the power supply are cut off; The two isolating switches are respectively called a first isolating switch and a second isolating switch; the DC constant voltage circuit is used for converting direct current voltage connected between the input end and the negative electrode into corresponding direct current voltage to be output between the output end and the negative electrode, the DC constant voltage circuit is provided with the input end, the negative electrode, the output end and a control end, when the control end of the DC constant current circuit is connected with a high level, the voltage connected between the input end and the negative electrode of the DC constant voltage circuit is converted into direct current to be output between the output end and the negative electrode, and when the control end of the DC constant current circuit is connected with a low level, the DC constant current circuit stops working, and the output current between the output end and the negative electrode of the DC constant current circuit is 0; The unidirectional conduction circuit is provided with an anode and a cathode, and the conduction current direction is from the anode to the cathode; the switch circuit is provided with a first connecting end, a second connecting end and a control end, when the control end is at a high level, the first connecting end and the second connecting end are conducted, and when the control end is at a low level, the first connecting end and the second connecting end are cut off; the logic control circuit is provided with an anode, a cathode, a first control end, a second control end and an output end, when the first control end of the logic control circuit is at a low level, if the second control end of the logic control circuit is connected with a positive voltage, the output end of the logic control circuit outputs a high level, if the second control end of the logic control circuit is not connected with the positive voltage, the output end of the logic control circuit outputs a low level, and when the first control end of the logic control circuit is at a high level, no matter whether the second control end of the logic control circuit is connected with the positive voltage or not, the output end of the logic control circuit outputs a high level; The first input end of the first isolating switch is a first live wire access end of the LED emergency power supply circuit and is a live wire output end of the LED emergency power supply circuit; the first input end of the second isolating switch is a second live wire access end of the LED emergency power supply circuit, the second input end of the first isolating switch is connected with the second input end of the second isolating switch, the connection end of the second isolating switch is a zero line access end of the LED emergency power supply circuit, the positive output end of the first isolating switch is respectively connected with the first control end of the logic control circuit and the control end of the DC constant current circuit, the negative output end of the second isolating switch is connected with the second control end of the logic control circuit, the positive output end of the second isolating switch, the positive electrode of the logic control circuit, The output end of the DC constant voltage circuit, the input end of the DC constant current circuit and the positive electrode of the storage battery are connected, the output end of the logic control circuit is connected with the control end of the switch circuit, the input end of the DC constant voltage circuit is connected with the positive electrode of the unidirectional conduction circuit, the connection end of the DC constant voltage circuit is the positive input end of the LED emergency power circuit, the output end of the DC constant current circuit is connected with the negative electrode of the unidirectional conduction circuit, the connection end of the DC constant current circuit is the positive output end of the LED emergency power circuit, and the first connection end of the switch circuit is the negative output end of the LED emergency power circuit; The negative electrode of the DC constant voltage circuit, the negative electrode of the DC constant current circuit, the negative output end of the first isolating switch, the second connecting end of the switch circuit and the negative electrode of the storage battery are connected, and the connecting end of the switch circuit is the negative input end of the LED emergency power supply circuit.

2. The LED emergency power supply circuit according to claim 1, wherein the first isolating switch comprises a first capacitor, a second capacitor, a first resistor, a second resistor, a first bridge stack, a first diode and a first optocoupler, the second capacitor is an electrolytic capacitor, the first diode is a zener diode, the first bridge stack has two ac input ends, a positive output end and a negative output end, the first optocoupler has an anode, a cathode, a collector and an emitter, one end of the first resistor is connected with one end of the first capacitor, the connection end of the first resistor is the first input end of the first isolating switch, the other end of the first resistor, the other end of the first capacitor is connected with one ac input end of the first bridge stack, the other ac input end of the first bridge stack is the second input end of the first isolating switch, the positive output end of the first bridge stack, the first diode, the first output end of the first diode, the negative output end of the first optocoupler is connected with the first output end of the first diode, the positive output end of the first optocoupler is the first output end of the first diode, the negative output end of the first optocoupler is connected with the first output end of the first diode; the second isolating switch comprises a third capacitor, a fourth capacitor, a third resistor, a fourth resistor, a second bridge stack, a second diode and a second optocoupler, wherein the fourth capacitor is an electrolytic capacitor, the second diode is a voltage stabilizing diode, the second bridge stack is provided with two alternating current input ends, a positive output end and a negative output end, the second optocoupler is provided with an anode, a cathode, a collector and an emitter, one end of the third resistor is connected with one end of the third capacitor, the connecting end of the second capacitor is a first input end of the second isolating switch, the other end of the third resistor, the other end of the third capacitor, the first alternating current input end of the second bridge stack, the other alternating current input end of the second bridge stack, the positive output end of the second bridge stack, the negative electrode of the fourth capacitor, the positive electrode of the fourth resistor, the negative output end of the fourth resistor, the positive output end of the fourth resistor, the second optocoupler and the negative output end of the second bridge are connected.

3. The LED emergency power supply circuit according to claim 1, wherein the logic control circuit comprises a fifth resistor, a sixth resistor, a third diode and a fourth diode, the third diode and the fourth diode are rectifier diodes, one end of the fifth resistor is a positive electrode of the logic control circuit, the other end of the fifth resistor is connected with the positive electrode of the fourth diode, the connection end of the fifth resistor is a first control end of the logic control circuit, the positive electrode of the third diode is a second control end of the logic control circuit, the negative electrode of the third diode, the negative electrode of the fourth diode and one end of the sixth resistor are connected, the connection end is an output end of the logic control circuit, and the other end of the sixth resistor is a negative electrode of the logic control circuit.

4. The LED emergency power supply circuit according to claim 1, wherein the switching circuit comprises a first MOS tube, the gate of the first MOS tube is the control end of the switching circuit, the drain of the first MOS tube is the first connection end of the switching circuit, and the source of the first MOS tube is the second connection end of the switching circuit.

5. The LED emergency power supply circuit according to claim 1, wherein the unidirectional conduction circuit is realized by a Schottky rectifier diode, the positive electrode of the Schottky rectifier diode is the positive electrode of the unidirectional conduction circuit, and the negative electrode of the Schottky rectifier diode is the negative electrode of the unidirectional conduction circuit.

6. The LED emergency power supply circuit according to claim 1, wherein the DC constant voltage circuit is a DC-DC step-down constant voltage circuit of the prior art, and the output voltage and the maximum output current of the DC-DC step-down constant voltage circuit can be preset.

7. The LED emergency power supply circuit according to claim 1, wherein the DC constant current circuit is a DC-DC boost constant current circuit in the prior art, and the output current of the DC-DC boost constant current circuit can be preset.