WO2020077954A1

WO2020077954A1 - Led power supply and redundant led power supply

Info

Publication number: WO2020077954A1
Application number: PCT/CN2019/080244
Authority: WO
Inventors: 江军; 邹超洋
Original assignee: 深圳市崧盛电子股份有限公司
Priority date: 2018-10-15
Filing date: 2019-03-28
Publication date: 2020-04-23
Also published as: CN209448928U

Abstract

An LED power supply and a redundant LED power supply. The LED power supply comprises an LED driving circuit (10), a switch circuit (30) connected to the LED driving circuit (10), and a voltage coupling circuit (20) connecting the LED driving circuit (10) and the switch circuit (30), wherein the voltage coupling circuit (20) is used for coupling a voltage from the LED driving circuit (10) so as to control the turning-on and turning-off of the switch circuit (30). The power supply is simple in circuit design and high in reliability.

Description

LED power supply and redundant LED power supply

Technical field

The utility model relates to the technical field of LED power supply, more specifically, relates to an LED power supply and a redundant LED power supply.

Background technique

In the existing LED power supply system, in order to improve reliability and facilitate maintenance and repair, a power supply system formed by connecting one or more main power equipment and a backup power equipment in parallel is usually used. Through this redundant structure to eliminate the single point of failure of the power system. In a power supply parallel redundant power supply system, when one of the power boards fails, the system needs to automatically remove the power board, and the other power boards jointly bear the extra system load to ensure the normal operation of other equipment in the system. At the same time, it also prevents one of its power supply outputs from short-to-ground faults from affecting the normal operation of other power supplies.

The traditional redundant power supply design uses diodes in an "OR gate" to output in parallel to the power bus to achieve redundancy. However, the current in the redundant power supply is very large. Due to the large voltage drop of the diode itself, the generated power consumption is very large, and a heat sink needs to be installed. Therefore, the traditional redundancy method using diode OR gates is inefficient and bulky. The other uses two DC power modules, four MOS tubes and two second controllers to form a redundant line. In this way, the circuit is more complicated and there are more components, and the reliability will be relatively reduced.

In the existing LED drive power supply technology, there are the following disadvantages:

1. When the output uses synchronous rectification, if the control is not good (no synchronous drive signal, or staggered parallel connection), it will generate circulating current, which is shown as an output positive current and a negative current. At this time, it is easy to damage the synchronous rectification MOS.

2. The existing simple increase in the output diode, its loss, high temperature and other defects make the efficiency of the whole machine low.

There is a special case when a short circuit occurs at the output end of a power supply, such as output diode breakdown. If the redundant module is not connected, the damaged power supply will pull the entire system off, causing a power outage accident.

technical problem

The technical problem to be solved by the present invention is to provide an LED power supply and a redundant LED power supply in view of the above-mentioned partial technical defects of the prior art.

Technical solution

The technical solution adopted by the utility model to solve its technical problems is to construct an LED power supply including an LED driving circuit, a switching circuit connected to the LED driving circuit, and a voltage coupling circuit connecting the LED driving circuit and the switching circuit The voltage coupling circuit is used to couple a voltage from the LED driving circuit to control the switching circuit on or off.

Preferably, the switch circuit includes a relay K1, an input terminal of the relay K1 is connected to the LED driving circuit, and a coil terminal of the relay K1 is connected to the voltage coupling circuit.

Preferably, the LED driving circuit includes an EMI circuit, a rectifier circuit, a PFC circuit, a PWM circuit, and a synchronous rectifier circuit connected in cascade in order, and a step-down circuit connecting the PFC circuit and the PWM circuit.

Preferably, the voltage coupling circuit is connected to the step-down circuit.

Preferably, the voltage coupling circuit includes a resistor R4, one end of the resistor R4 is connected to the output end of the step-down circuit, and the other end of the resistor R4 is connected to the coil end of the relay K1.

Preferably, the voltage coupling circuit is connected to the synchronous rectification circuit.

Preferably, the voltage coupling circuit includes a resistor R4 ^' and a capacitor C1, one end of the resistor R4' is connected to the output end of the synchronous rectifier circuit, and the other end of the resistor R4 'is connected to the coil end of the relay K1 and The capacitor C1 is grounded via the capacitor C1.

Preferably, the relay K1 is a normally open relay.

Preferably, the model of the relay K1 is T73.

In addition, the present invention also constructs a redundant LED power supply, including at least two LED power supplies as described in any one of the above, the at least two LED power supplies are connected in parallel.

A

Beneficial effect

The implementation of the LED power supply and redundant LED power supply of the present invention has the following beneficial effects: the circuit design is simple and the reliability is high.

BRIEF DESCRIPTION

The utility model will be further described below with reference to the drawings and embodiments. In the drawings:

1 is a circuit schematic diagram of a first embodiment of an LED power supply of the present invention;

2 is a circuit schematic diagram of a second embodiment of an LED power supply of the present invention;

3 is a circuit schematic diagram of a third embodiment of an LED power supply of the present invention;

4 is a circuit schematic diagram of a fourth embodiment of an LED power supply of the present invention;

5 is a circuit schematic diagram of a fifth embodiment of an LED power supply of the present invention.

Embodiments of the invention

In order to have a clearer understanding of the technical features, purposes and effects of the present invention, the specific implementation of the present invention will now be described in detail with reference to the drawings.

As shown in FIG. 1, in a first embodiment of an LED power supply of the present invention, it includes an LED driving circuit 10, a switching circuit 30 connected to the LED driving circuit 10, and a voltage coupling connecting the LED driving circuit 10 and the switching circuit 30 The circuit 20 and the voltage coupling circuit 20 are used to couple a voltage from the LED driving circuit 10 to control the switching circuit 30 to be turned on or off. Specifically, the LED drive circuit 10 converts the AC input into a DC output, and the DC output is connected to the LED to be powered through the switch circuit 30, and here, from the LED drive circuit 10 through the voltage coupling circuit 20 connected to the LED drive circuit 10 The coupling voltage is used to control the switching circuit 30 to be turned on or off, so that the DC output of the LED driving circuit 10 is connected to the LED to be powered.

Further, the switch circuit 30 includes a relay K1, an input terminal of the relay K1 is connected to the LED driving circuit 10, and a coil terminal of the relay K1 is connected to the voltage coupling circuit 20. Specifically, the relay K1 controls the DC output of the LED drive circuit 10 to be connected or disconnected from the LED to be powered, where the input of the relay K1 is connected to the LED drive circuit 10, and the output of the relay K1 is connected to the LED to be powered, and the relay K1 Is connected to the voltage coupling circuit 20. When the LED drive circuit 10 works, the voltage coupling circuit 20 is coupled to the voltage from the LED drive circuit 10, and the coupled voltage is output to the coil end of the relay K1, so that the coil of the relay K1 has a current through Then, the output end of the suction relay K1 is closed, and the output of the LED driving circuit 10 is turned on to supply power to the LED to be powered, so that the LED can work normally.

Further, as shown in the embodiments shown in FIG. 2 to FIG. 5, the LED driving circuit 10 includes an EMI circuit 11, a rectifier circuit 12, a PFC circuit 13, a PWM circuit 14, and a synchronous rectifier circuit 15 connected in cascade in order, and a PFC connection The step-down circuit 16 of the circuit 13 and the PWM circuit 14. Specifically, the LED drive circuit 10 includes an EMI circuit 11 connected to the AC input to protect the circuit input, the rectifier circuit 12 is used to rectify the AC input to obtain DC, and the PFC circuit 13 is used to boost the rectified output DC High voltage DC and power factor correction, PWM circuit 14 is used to convert the high voltage DC voltage into an isolated low voltage output through the transformer, synchronous current circuit 15 is used to rectify the low voltage to obtain the low voltage DC output; step-down circuit 16 is used to Convert high-voltage DC into non-isolated low-voltage DC voltage VCC to power PFC, PWM control IC, etc.

Further, the voltage coupling circuit 20 is connected to the step-down circuit 16. Specifically, in the embodiments shown in FIGS. 2 and 3, the voltage coupling circuit 20 is connected to the step-down circuit 16, and the coupling voltage is obtained by coupling the output of the step-down circuit 16 to control the operation of the switching circuit 30.

Further, as shown in FIG. 3, the voltage coupling circuit 20 includes a resistor R4, one end of the resistor R4 is connected to the output end of the step-down circuit 16, and the other end of the resistor R4 is connected to the coil end of the relay K1. Specifically, the output of the step-down circuit 16 provides an auxiliary voltage VCC, and the auxiliary voltage VCC is supplied to the relay K1 after the current is limited by the resistor R4, so that the output terminal of the relay K1 is closed, and the output is turned on. When the auxiliary voltage VCC disappears, the relay K1 is in the off state. At this time, it effectively prevents the voltage back-feeding of other power supplies or affects the normal operation of other power supplies.

Further, as shown in FIGS. 4 and 5, the voltage coupling circuit 20 is connected to the synchronous rectification circuit 15. Specifically, the voltage may be coupled from the output voltage of the synchronous rectifier circuit 15, and here it may also be understood that the voltage is coupled from the power supply voltage of the LED to be powered to control the operation of the switching circuit 30.

Further, as shown in FIG. 5, the voltage coupling circuit 20 includes a resistor R4 ^′ and a capacitor C1, one end of the resistor R4 ^′ is connected to the output end of the synchronous rectifier circuit 15, and the other end of the resistor R4 ^′ is connected to the coil end of the relay K1 and the capacitor C1 And grounded via capacitor C1. specific,

Further, the relay K1 is a normally open relay. Specifically, when the relay K1 is in an open state, only when a current flows through the coil end, it is closed to turn on the input and output. The type of relay K1 here is T73.

In addition, the present invention also constructs a redundant LED power supply, including at least two LED power supplies as described above, and at least two LED power supplies are connected in parallel. Specifically, by connecting multiple LED power supplies in parallel, the output current of each LED power supply can be reduced, and the consumption of a single LED power supply can be reduced. At the same time, the LED power supply is damaged, or the LED drive circuit 10 has abnormal output or no input. The switch circuit 30 connected behind the LED driving circuit 10 will be disconnected, which can effectively avoid the voltage back-feeding of other power supplies or affect the normal operation of other power supplies.

It is understandable that the above example only expresses the preferred embodiment of the utility model, and its description is more specific and detailed, but it should not be construed as a limitation of the patent scope of the utility model; it should be noted that For technical personnel, without departing from the idea of the utility model, the above technical features can be freely combined, and several modifications and improvements can be made. These are all within the scope of protection of the utility model; Equivalent transformations and modifications made in the scope of the new claims shall fall within the scope of the claims of the present utility model.

Claims

An LED power supply is characterized by comprising an LED drive circuit, a switch circuit connected to the LED drive circuit, a voltage coupling circuit connecting the LED drive circuit and the switch circuit, the voltage coupling circuit used to The LED driving circuit is coupled with a voltage to control the switching circuit on or off.
The LED power supply according to claim 1, wherein the switching circuit includes a relay K1, an input terminal of the relay K1 is connected to the LED driving circuit, and a coil terminal of the relay K1 is connected to the voltage coupling circuit.
The LED power supply according to claim 2, wherein the LED driving circuit includes an EMI circuit, a rectifier circuit, a PFC circuit, a PWM circuit, and a synchronous rectifier circuit connected in cascade in order, and the PFC circuit is connected to the Buck circuit of PWM circuit.
The LED power supply according to claim 3, wherein the voltage coupling circuit is connected to the step-down circuit.
The LED power supply according to claim 4, wherein the voltage coupling circuit includes a resistor R4, one end of the resistor R4 is connected to the output end of the step-down circuit, and the other end of the resistor R4 is connected to the relay The coil end of K1.
The LED power supply according to claim 3, wherein the voltage coupling circuit is connected to the synchronous rectification circuit.
The LED power supply according to claim 6, wherein the voltage coupling circuit includes a resistor R4 ' and a capacitor C1, one end of the resistor R4 ' is connected to the output end of the synchronous rectifier circuit, and the resistor R4 ' The other end is connected to the coil end of the relay K1 and the capacitor C1, and is grounded via the capacitor C1.
The LED power supply according to claim 2, wherein the relay K1 is a normally open relay.
The LED power supply according to claim 8, wherein the model of the relay K1 is T73.
A redundant LED power supply, comprising at least two LED power supplies according to any one of claims 1-9, the at least two LED power supplies being connected in parallel.

A