Power supply aging test device with under-voltage protection module

Abstract

The utility model discloses a power supply aging test device with an under-voltage protection module, and the device comprises the under-voltage protection module which is connected between a programmable energy-saving load and a grid-connected inverter, and the under-voltage protection module comprises a relay which controls the connection and disconnection of a connection path between the grid-connected inverter and the programmable energy-saving load; the detection unit is used for detecting the voltage of the input end of the grid-connected inverter and controlling the work of the relay according to the detection result so as to conduct or close the connection path; and when the input end voltage is reduced below the threshold voltage, the relay is opened, and the connection path is closed. The aging test device provided by the utility model solves the technical problems that the front-end programmable energy-saving load and the power converter are damaged due to the fault of the grid-connected inverter in the prior art, and the input end is powered on before the grid-connected inverter accesses the network.

Description

TECHNICAL FIELD

[0001] The utility model relates to electronic product test field, concretely, a power supply aging test device with under -voltage protection module is provided. BACKGROUND

[0002] With the power of various electronic products unceasing enhancement, the reliability requirement of power supply is higher and higher, and the power supply is the core component of electronic products, and its manufacturing process must go through strict aging test to ensure reliability. One of the power supplies is a grid-connected power supply, which can be called a power converter. The power converter is used to convert the power from the grid to supply the equipment, for example: AC-DC power supply, new energy vehicle charging cabinet, etc. In order to meet the needs of energy saving and environmental protection, the aging test process of these power converters generally adopts the energy recovery mode, and the grid power is converted by the power converter and then merged into the grid to realize energy recovery. Figure 1 It is the block diagram of the existing energy recovery power supply aging test device, and its working principle is as follows:

[0003] The power converter is pulled by the programmable energy-saving load controlled by the upper computer, and the programmable energy-saving load is actually a programmable DC-DC converter, which is responsible for pulling the output of the power converter to the rated value power, and at the same time, the voltage is raised to DC800V output to the grid-connected inverter, and then the energy is delivered back to the grid by the grid-connected inverter, so that the aging test of the measured power converter is realized and the energy saving and environmental protection requirements are met.

[0004] Due to the characteristics of the grid-connected inverter itself, the aging test device has the following defects:

[0005] 1. The grid-connected inverter must be initialized and self-checked before entering the grid-connected state each time it is powered on, and the input end of the inverter is not allowed to have external voltage input before the inverter enters the grid-connected state, that is, the programmable logic load end has no input DC800V voltage to the grid-connected inverter, otherwise the grid-connected inverter will be damaged. The staff often neglects this point, and starts the aging test device before the grid-connected inverter enters the grid-connected state, which causes the inverter to be damaged.

[0006] 2. In the device, the grid-connected inverter is responsible for energy delivery and works in a high-voltage and high-current environment for a long time, which belongs to a fault-prone component. If the grid-connected inverter suddenly fails during the aging test process, the fault type is mostly internal IGBT tube breakdown, which causes the input end of the grid-connected inverter to be short-circuited. This situation not only causes the programmable energy-saving load in the front stage to be damaged, but also damages the measured product. INVENTION CONTENTS

[0007] The utility model discloses a power supply aging test device with under -voltage protection module, and it is designed to solve the technical problem of grid-connected inverter fault, which leads to the damage of front programmable energy-saving load and power converter, and the power-on of grid-connected inverter input end before grid connection.

[0008] The utility model provides a power supply aging test device with under -voltage protection module, the device includes: the power converter of measured electric connection in proper order, programmable energy-saving load and grid-connected inverter, programmable energy-saving load is DCDC converter, is used for converting the voltage in power converter into DC voltage and then output to the grid-connected inverter, and the grid-connected inverter is used for inverting programmable energy-saving load electric energy into AC power and output to the grid, and it is characterized in that, the under -voltage protection module is electrically connected between programmable energy-saving load and the grid-connected inverter, when the grid-connected inverter fails or short-circuit, disconnects the connecting path of the grid-connected inverter and programmable energy-saving load, to protect programmable energy-saving load and power converter, and the under -voltage protection module includes:

[0009] Relay, the relay is connected between programmable energy-saving load and the grid-connected inverter, and is used for controlling the on and off of the connecting path between the grid-connected inverter and programmable energy-saving load;

[0010] Detection unit, one end of the detection unit is electrically connected with the input end of the grid-connected inverter, and the other end is electrically connected to the relay, and the detection unit is used for detecting the input end voltage of the grid-connected inverter, and controlling the operation of the relay according to the detection result, so as to turn on or turn off the connecting path;

[0011] Wherein, when the input end voltage is normal working voltage, the relay is closed, and the connecting path is turned on, and when the input end voltage is reduced to below the threshold voltage, the relay is opened, and the connecting path is closed.

[0012] The power supply aging test device disclosed by the utility model, when the power converter is powered on for the first time through the programmable energy-saving load and the under -voltage protection module, the relay is in the open state, and the grid-connected inverter input end has no voltage, so that the relay controlled by the detection unit is in the open state, and the grid-connected inverter has no input, which will not cause the damage of the grid-connected inverter;When the grid-connected inverter has been connected to the grid, the relay is manually closed, at this time, the DC voltage enters the grid-connected inverter through the relay, so as to detect the power converter and connect the detected electric energy to the grid, which does not waste resources and realizes the purpose of environmental protection.

[0013] When the grid-connected inverter is working normally, the detection unit outputs a control signal to control the relay to be closed, maintaining the connection path to be conductive, so as to realize normal working; when the grid-connected inverter is damaged, the input end of the grid-connected inverter is short-circuited, and has a low voltage, at this time, the detection unit outputs a control signal to control the relay to be opened, and the connection path is closed, so as to prevent damage to the front-end programmable energy-saving load and the power converter. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 is a module schematic diagram of the testing device of the utility model;

[0015] Figure 2 is a circuit principle diagram of the under-voltage protection module of the utility model. DETAILED DESCRIPTION

[0016] The utility model will be further described and explained in combination with specific embodiments and the drawings of the specification:

[0017] Please refer to Figure 1 The utility model provides a kind of power aging testing device with under-voltage protection module, the device includes: the power converter 10 of measured electrical connection in turn, programmable energy-saving load 20 and grid-connected inverter 40;The programmable energy-saving load 20 is DCDC converter, for converting the voltage in power converter 10 into DC voltage and then output to the grid-connected inverter 40, and the grid-connected inverter 40 is used to convert the electrical energy of programmable energy-saving load 20 into AC and output to the grid.

[0018] The programmable energy-saving load 20 is electrically connected with under-voltage protection module 30 between the grid-connected inverter 40, and the under-voltage protection module 30 disconnects the connection path between the grid-connected inverter 40 and the programmable energy-saving load 20 when the grid-connected inverter 40 fails or short-circuits, to protect the programmable energy-saving load 20 and power converter 10;The under-voltage protection module 30 includes:

[0019] Relay K1, the relay K1 is connected between the programmable energy-saving load 20 and the grid-connected inverter 40, for controlling the conduction and closing of the connection path between the grid-connected inverter 40 and the programmable energy-saving load 20;

[0020] Detection unit 31, one end of the detection unit 31 is electrically connected with the input end of the grid-connected inverter 40, and the other end is electrically connected to the relay K1;The detection unit 31 is used to detect the input end voltage of the grid-connected inverter 40, and controls the working of the relay K1 according to the detection result, to conduct or close the connection path;

[0021] Wherein, the input voltage is normal working voltage, the relay K1 is closed, the connection path is turned on, the input voltage is reduced to threshold voltage, the relay K1 is opened, and the connection path is closed.

[0022] The power supply aging test device discloses the utility model, in the power converter 10 through programmable energy-saving load 20 and under voltage protection module 30 first power on, relay K1 is in the open state, and the grid-connected inverter 40 input end has no voltage, thereby causing the relay K1 of detection unit 31 control is in the open state, and the grid-connected inverter 40 has no input, and will not cause the damage of grid-connected inverter 40, when the grid-connected inverter 40 has been grid-connected, relay K1 is manually closed, at this time, direct current voltage passes through relay K1 and enters grid-connected inverter 40, thereby detecting the power converter 10 at the same time and the electric energy of detection is incorporated into the grid, and the purpose of environmental protection is realized.

[0023] Wherein, when the grid-connected inverter 40 is normal, the detection unit 31 output control signal controls the relay K1 to close, and the connection path is turned on, thereby realizing normal work, when the grid-connected inverter 40 is damaged, the input end of the grid-connected inverter 40 is short-circuited, and has low voltage, at this time, the detection unit 31 output control signal controls the relay K1 to open, and the connection path is closed, thereby preventing the damage of the front programmable energy-saving load 20 and the power converter 10.

[0024] As Figure 2 , the utility model discloses the detection unit 31 includes: operational amplifier U1 and triode.

[0025] The operational amplifier U1 includes the same phase input end and the different phase input end and the output end, the different phase input end is connected with constant voltage source through the first resistance R1, and the different phase input end is grounded through the second resistance R2, the same phase input end is connected with the input end of grid-connected inverter 40 through the third resistance R3 and the fourth resistance R4, and the third resistance R3 and the fourth resistance R4 are parallel to each other, the output end is connected to the output end, the base of triode is connected with the output end through the fifth resistance R5, the emitter of triode is grounded, and the collector of triode is connected to one end of the relay K1, and the other end of the relay K1 is connected with the constant voltage source.

[0026] Wherein, the grid-connected inverter 40 includes the positive input end and the negative input end, the third resistance R3 is electrically connected to the positive input end, and the fourth resistance R4 is electrically connected to the negative input end.

[0027] Wherein, the relay K1 also includes freewheeling diode D1, the anode of freewheeling diode D1 is electrically connected with the triode collector, and the cathode of freewheeling diode D1 is electrically connected with the constant voltage source.

[0028] Wherein, when the normal working voltage of the input end of the grid-connected inverter 40, the output end of the operational amplifier U1 outputs high level, so that the triode is turned on, the constant voltage source flows into the ground through the relay K1, forming a conduction path, and the relay K1 is closed.

[0029] Wherein, when the input end voltage of the grid-connected inverter 40 is reduced to below the threshold voltage, the output end of the vertigo amplifier outputs low level, so that the triode is cut off, the conduction path of the constant voltage source through the relay K1 is disconnected, and the relay K1 is opened.

[0030] In the utility model, the normal working voltage is 800V±10%; the threshold voltage is 10V.

[0031] It should be noted finally that the above examples are only used to illustrate the technical solutions of the utility model, and are not limited to the protection scope of the utility model. Although the utility model has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the utility model can be modified or replaced equivalently without departing from the essence and scope of the technical solutions of the utility model.

Claims

1. A power supply burn-in test apparatus with an under-voltage protection module, the apparatus comprising: The measured power converter, the programmable energy-saving load and the grid-connected inverter are electrically connected in sequence; The programmable energy-saving load is a DC-DC converter, which is used to convert the voltage in the power converter into a direct current voltage and then output to the grid-connected inverter; the grid-connected inverter is used to convert the electric energy of the programmable energy-saving load into an alternating current and then output to the power grid; characterized in that, between the programmable energy-saving load and the grid-connected inverter, there is also an under-voltage protection module electrically connected; when the grid-connected inverter fails or is short-circuited, the under-voltage protection module disconnects the connection path between the grid-connected inverter and the programmable energy-saving load, so as to protect the programmable energy-saving load and the power converter; the under-voltage protection module comprises: a relay connected between the programmable energy-saving load and the grid-connected inverter, which is used to control the conduction and closing of the connection path between the grid-connected inverter and the programmable energy-saving load; a detection unit electrically connected to one end of the grid-connected inverter and the other end of the relay; the detection unit is used to detect the input voltage of the grid-connected inverter and control the operation of the relay according to the detection result, so as to conduct or close the connection path; wherein, when the input voltage is a normal working voltage, the relay is closed and the connection path is conducted; when the input voltage is reduced to below a threshold voltage, the relay is opened and the connection path is closed.

2. The power aging test apparatus with an under-voltage protection module as claimed in claim 1, wherein The detection unit comprises: an operational amplifier comprising a same-phase input end, an opposite-phase input end and an output end; the opposite-phase input end is connected to a constant voltage source through a first resistor and grounded through a second resistor; the same-phase input end is connected to the input end of the grid-connected inverter through a third resistor and a fourth resistor, and the third resistor and the fourth resistor are connected in parallel with each other; the output end is connected to the output end; a triode, the base of the triode is connected to the output end through a fifth resistor; the emitter of the triode is grounded, and the collector of the triode is connected to one end of the relay, and the other end of the relay is connected to the constant voltage source; wherein, when the input end of the grid-connected inverter is a normal working voltage, the output end of the operational amplifier outputs a high level, so that the triode is conducted, the constant voltage source flows into the ground through the relay, and a conduction path is formed, and the relay is closed; when the input voltage of the grid-connected inverter is reduced to below a threshold voltage, the output end of the operational amplifier outputs a low level, so that the triode is cut off, the conduction path of the constant voltage source through the relay is disconnected, and the relay is opened.

3. The power aging test apparatus with an under-voltage protection module as claimed in claim 2, wherein The normal working voltage is 800V±10%; the threshold voltage is 10V.

4. The power aging test apparatus with an under-voltage protection module as claimed in claim 2, wherein The grid-connected inverter comprises a positive input end and a negative input end; the third resistor is electrically connected to the positive input end, and the fourth resistor is electrically connected to the negative input end.

5. The power aging test apparatus with an under-voltage protection module as claimed in claim 2, wherein The relay further comprises a freewheeling diode, the anode of the freewheeling diode is electrically connected to the collector of the triode, and the cathode of the freewheeling diode is electrically connected to the constant voltage source.

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