Anti-misconnection test system of inverter

Abstract

The utility model discloses a misconnection prevention test system of an inverter. The system comprises a misconnection prevention detection circuit and an inverter. The inverter comprises at least two direct current input paths; the anti-misconnection detection circuit comprises a control loop and a main loop. The control loop comprises a control module and a starting module; the starting module controls the main loop to be electrified; the control module controls the output voltage of the main loop; the main loop comprises at least two voltage dividing modules; the voltage dividing module divides the voltage to output test voltages of different voltage levels; at least two paths of direct current input ends of the inverter are electrically connected with the at least two voltage division modules respectively, and a voltage acquisition circuit of the inverter acquires at least two paths of direct current input voltages received by the inverter and generates at least two paths of direct current voltage signals according to the at least two paths of direct current input voltages. According to the utility model, the inspection efficiency and accuracy of internal wiring of the inverter are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of inverters, and particularly relates to a misconnection prevention test system for an inverter. Background Art

[0002] With the increasing pollution of the global environment, the concepts of green development and environmental protection are being paid more and more attention by people. As a green energy source, photovoltaic power generation has received extensive attention from people, and its application has become more and more popular, promoting the continuous development of new energy power facilities. As an important component in photovoltaic power generation, the reliability of the inverter is also crucial.

[0003] If the inverter has two or more DC input paths, there will be more wiring inside the inverter. During the assembly process of the inverter, there is a problem of misconnection in the internal wiring, which may cause the inverter to malfunction during use, thus affecting the reliability of the power transmission line. In related technologies, usually manual inspection of the internal wiring of the inverter is adopted, and its inspection efficiency is low and the accuracy is poor. Summary of the Utility Model

[0004] The utility model provides a misconnection prevention test system for an inverter to solve the problems of low inspection efficiency and poor accuracy in the inspection of the internal wiring of the inverter.

[0005] According to one aspect of the utility model, a misconnection prevention test system for an inverter is provided, including: a misconnection prevention detection circuit and the inverter; the inverter includes at least two DC input paths, and one DC input path corresponds to one DC input terminal;

[0006] The misconnection prevention detection circuit includes: a control circuit and a main circuit;

[0007] The control circuit includes a control module and a start module; the power supply terminal of the start module is connected to the grid voltage, the control terminal of the start module is connected to the main circuit, and the start module is used to be powered on after receiving a start signal and control the main circuit to be powered on; the control module is connected to the main circuit and is used to control the output voltage of the main circuit;

[0008] The main circuit includes at least two voltage dividing modules; the voltage dividing module is used to divide the voltage to output test voltages of different voltage levels;

[0009] At least two of the DC input terminals of the inverter are respectively electrically connected to at least two of the voltage dividing modules, and the voltage acquisition circuit of the inverter acquires at least two DC input voltages received by the inverter and generates at least two DC voltage signals according to the at least two DC input voltages.

[0010] Optionally, the main circuit further includes a rectification module; the output terminals of the rectification module include: a positive output terminal and a negative output terminal; at least two of the voltage dividing modules are connected in series between the positive output terminal and the negative output terminal of the rectification module;

[0011] Each of the voltage dividing modules is provided with an output terminal, the positive output terminal of the rectification module and the connection points of two adjacent voltage dividing modules respectively serve as the output terminals of the voltage dividing modules; the output terminals of each of the voltage dividing modules are respectively connected to the positive extreme ends of the DC input terminals of one path of the inverter, and the negative output terminal of the rectification module is connected to the negative extreme end of the DC input terminal.

[0012] Optionally, the main circuit includes: a voltage dividing switch;

[0013] The voltage dividing switch and at least two of the voltage dividing modules are connected in series between the positive output terminal and the negative output terminal of the rectification module; the control terminal of the voltage dividing switch is connected to the control module, and the voltage dividing switch is controlled by the control module.

[0014] Optionally, the voltage dividing module includes: at least one voltage dividing resistor connected in series and / or in parallel.

[0015] Optionally, the anti-misconnection test system of the inverter further includes: a first power supply line, a second power supply line, a third power supply line, a fourth power supply line, and a fifth power supply line for accessing the grid voltage; wherein, the first power supply line and the third power supply line access the same grid voltage;

[0016] The power supply terminal of the control circuit includes: a first live wire terminal and a neutral wire terminal; the first live wire terminal is electrically connected to the first power supply line, and the neutral wire terminal is electrically connected to the second power supply line;

[0017] The power supply terminal of the main circuit includes: a first power supply terminal, a second power supply terminal, and a third power supply terminal; the first power supply terminal is electrically connected to the third power supply line, the second power supply terminal is electrically connected to the fourth power supply line, and the third power supply terminal is electrically connected to the fifth power supply line.

[0018] Optionally, the starting module includes: a starting switch, a first relay coil, and a second relay coil; two first relay contacts are correspondingly arranged for the first relay coil, and three second relay contacts are correspondingly arranged for the second relay coil;

[0019] The starting switch and the first relay coil are connected in series between the first power supply line and the second power supply line; the second relay coil is connected in parallel with the first relay coil;

[0020] The two first relay contacts are respectively connected in series in the first power supply line and the second power supply line; the three second relay contacts are respectively connected in series in the third power supply line, the fourth power supply line and the fifth power supply line.

[0021] Optionally, the anti-misconnection detection circuit further includes: a first switch, a second switch and a third switch;

[0022] The four first switches are respectively connected in series in the first power supply terminal, the second power supply terminal, the third power supply terminal and the neutral line terminal;

[0023] The two second switches are respectively connected in series in the first power supply line and the second power supply line;

[0024] The three third switches are respectively connected in series in the third power supply line, the fourth power supply line and the fifth power supply line.

[0025] Optionally, the anti-misconnection detection circuit further includes: an emergency stop switch;

[0026] The emergency stop switch, the start switch and the first relay coil are connected in series; the emergency stop switch is used to cut off the power supply of the control circuit and the main circuit.

[0027] Optionally, the rectification module includes: a photovoltaic simulator;

[0028] The first input terminal of the photovoltaic simulator is connected to the third power supply line, the second input terminal of the photovoltaic simulator is connected to the fourth power supply line, the third input terminal of the photovoltaic simulator is connected to the fifth power supply line, and the positive output terminal and the negative output terminal of the photovoltaic simulator output direct current.

[0029] Optionally, the anti-misconnection detection circuit further includes: a cooling fan;

[0030] The cooling fan is connected between the first power supply line and the second power supply line; the control terminal of the cooling fan is connected to the control module.

[0031] Optionally, the anti-misconnection test system of the inverter further includes: a host computer;

[0032] The host computer is connected to the control module, and the host computer is used to send instructions to the control module; the host computer is also used to receive the voltage collected by the voltage acquisition circuit of the inverter.

[0033] In the technical solution provided by the embodiment of the present utility model, an anti-misconnection detection circuit is provided. A plurality of voltage division modules in the circuit can generate test voltages of different levels, and correspondingly input them into the DC input terminals of each path of the inverter. Then, by collecting the DC input signals of the DC input voltages of each path generated inside the inverter by the test voltages of different levels, it can be determined whether there is misconnection in the internal wiring of the inverter. The embodiment of the present utility model realizes the automatic test of the internal wiring of the inverter, without manual inspection, has high test efficiency, and judges the internal wiring by comparing voltages, with high accuracy.

[0034] It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the present utility model, nor is it used to limit the scope of the present utility model. Other features of the present utility model will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0036] Figure 1 is a schematic structural diagram of an anti-misconnection test system for an inverter provided by an embodiment of the present utility model;

[0037] Figure 2 is a schematic structural diagram of another anti-misconnection test system for an inverter provided by an embodiment of the present utility model;

[0038] Figure 3 is a schematic structural diagram of yet another anti-misconnection test system for an inverter provided by an embodiment of the present utility model;

[0039] Figure 4 is a circuit diagram of an anti-misconnection detection circuit for an inverter provided by an embodiment of the present utility model;

[0040] Figure 5 is a circuit diagram of another anti-misconnection detection circuit for an inverter provided by an embodiment of the present utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0041] To enable those skilled in the art to better understand the solution of the present utility model, the technical solutions in the embodiments of the present utility model will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0042] It should be noted that the terms "first", "second", etc. in the specification and claims of the present utility model and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily need to be used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present utility model described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products, or devices.

[0043] The embodiment of the present utility model provides an anti-misconnection test system for an inverter, which is applicable to an inverter with at least two DC input paths, and is particularly applicable to a photovoltaic inverter. Figure 1 It is a schematic structural diagram of an anti-misconnection test system for an inverter provided by an embodiment of the present utility model. Refer to Figure 1 , the test system includes: an anti-misconnection detection circuit (including a control loop 1 and a main loop 2) and an inverter 3. The inverter 3 includes at least two DC input paths, and one DC input path corresponds to one DC input terminal. The control loop 1 includes a control module 11 and a start module 12; the power supply terminal of the start module 12 is connected to the grid voltage, the control terminal of the start module 12 is connected to the main loop 2, and the start module 12 is used to be powered on after receiving a start signal and control the main loop 2 to be powered on; the control module 11 is connected to the main loop 2 and is used to control the output voltage of the main loop 2. The main loop 2 includes at least two voltage dividing modules (for example, voltage dividing module 221, voltage dividing module 222,..., voltage dividing module 22n); the voltage dividing module 22 is used to divide the voltage to output test voltages of different voltage levels. At least two DC input terminals of the inverter 3 are respectively electrically connected to at least two voltage dividing modules 22, and the voltage acquisition circuit of the inverter 3 acquires at least two DC input voltages received by the inverter 3, generates at least two DC voltage signals according to the at least two DC input voltages, and uploads them to the control module 11.

[0044] Exemplarily, the principle of the anti-misconnection test system for testing the internal wiring of the inverter is that when a test is required, after the start module 12 receives the start signal, it connects the control circuit 1 to the power grid, and at the same time, the start module 12 also connects the main circuit 2 to the power grid. The control circuit 1 and the main circuit 2 are powered on. At this time, the start module 12 controls the main circuit 2 to be powered on, and the voltage dividing module 22 generates an induced voltage. Different voltage dividing modules 22 can divide the induced voltage into test voltages of different levels and input them into different DC input terminals of the inverter 3.

[0045] The inverter 3 has at least two DC input paths, which can also be referred to as MPPT paths. Each DC input path corresponds to a DC input terminal. Each DC input terminal is connected to a photovoltaic module in the form of a terminal block. Each DC input terminal includes a positive input terminal and a negative input terminal. For example, when the inverter 3 has n DC input terminals, the first DC input terminal may include a positive input terminal PV1+ and a negative input terminal, the second DC input terminal includes a positive input terminal PV2+ and a negative input terminal,..., and the nth DC input terminal may be provided with a positive input terminal PVn+ and a negative input terminal. Since the negative input terminals of each DC input terminal are short-circuited inside the inverter 3, that is, the negative input terminals from the first DC input terminal to the nth DC input terminal are shared, therefore, for simplicity of representation, Figure 1 only one negative input terminal PV- is shown.

[0046] Taking two DC input terminals as an example, the positive input terminal PV1+ of the first DC input terminal is connected to the test voltage of the first voltage level; the positive input terminal PV2+ of the second DC input terminal is connected to the test voltage of the second voltage level; the negative input terminal PV- is connected to the common negative of the test voltages of the first voltage level and the second voltage level. If the internal wiring of the inverter 3 is correct, then the voltage acquisition circuit corresponding to the first DC input terminal should acquire the sampling voltage of the first voltage level, and the voltage acquisition circuit of the second DC input terminal should acquire the sampling voltage of the second voltage level.

[0047] Under normal circumstances, at least two lines led out from the DC input terminal will be connected to the DC switch and then connected to the power board inside the inverter 3. However, when wiring between the DC input terminal and the DC switch, there is a risk of misconnection; similarly, when wiring between the DC switch and the power board, there is also a risk of misconnection. The more DC input paths there are, the greater the risk of misconnection.

[0048] The voltage of each output of the main circuit provided by the embodiment of the present utility model is known. The voltage acquisition circuit of the inverter 3 can acquire the DC input voltages of each path and generate DC voltage signals. Exemplarily, the voltage acquisition circuit can acquire the voltage of the input power board. If the internal wiring of the inverter 3 is correct, the test voltage input to the inverter 3 by the voltage division module 22 and the DC voltage signal generated inside the inverter 3 should be the same voltage. Still taking the number of two DC input paths as an example, if the voltage acquisition circuit corresponding to the first DC input end acquires a sampling voltage that is not of the first voltage level, and / or the voltage acquisition circuit corresponding to the second DC input end acquires a sampling voltage that is not of the second voltage level, it indicates that there is a wrong connection in the internal wiring of the inverter 3.

[0049] For the technical solution provided by the embodiment of the present utility model, an anti-wrong connection detection circuit is provided. Different levels of test voltages can be generated by multiple voltage division modules 22 in the circuit and correspondingly input into each DC input end of the inverter 3. Then, by acquiring the DC input signals of the DC input voltages generated inside the inverter 3 for different levels of test voltages, it can be determined whether there is a wrong connection in the internal wiring of the inverter 3. The embodiment of the present utility model realizes the automatic test of the internal wiring of the inverter 3, without manual inspection, with high test efficiency, and has high accuracy by comparing voltages to judge the internal wiring.

[0050] Figure 2 FIG. is a schematic structural diagram of an anti-wrong connection test system for another inverter provided by an embodiment of the present utility model. Refer to Figure 2 , on the basis of the above embodiments, optionally, the main circuit 2 further includes a rectification module 21. The output terminals of the rectification module 21 include: a positive output terminal DC+ and a negative output terminal DC-. At least two voltage division modules 22 are connected in series between the positive output terminal DC+ and the negative output terminal DC- of the rectification module 21. Each voltage division module 22 is provided with an output terminal. The positive output terminal DC+ of the rectification module 21 and the connection points of adjacent two voltage division modules 22 are respectively used as the output terminals of the voltage division module; the output terminals of each voltage division module 22 are respectively connected to the positive extreme of the DC input end of one path of the inverter 3, and the negative output terminal DC- of the rectification module 21 is connected to the negative extreme of the DC input end.

[0051] Among them, the rectification module 21 can receive the alternating current input to the main circuit 2 by the power grid and convert the alternating current into direct current. The control module 11 also controls the rectification module 21 to output a set voltage, and the set voltage is adjustable. The output voltage of the rectification module 21 is input into the voltage division module 22. Different voltage division modules 22 can divide the output voltage of the rectification module 21 into different levels of test voltages and input them into different DC input ends of the inverter 3. Exemplarily, such as Figure 2As shown, the number of voltage dividing modules 22 is two, which can output test voltages of two voltage levels. Since the negative input terminals of the first and second DC input terminals of the inverter share the same connection, the negative poles of the test voltages of the two voltage levels share the same connection. The positive output terminal DC+ of the rectification module 21 is connected to the positive terminal of a DC input terminal of the inverter 3, the connection point between two adjacent voltage dividing modules 22 is connected to the positive terminal of a DC input terminal of the inverter 3, and the negative output terminal DC- is connected to the negative terminal of the DC input terminal of the inverter 3. Through this connection method, the output voltage of each voltage dividing module can be corresponded to each DC input terminal of the inverter 3, so as to perform a misconnection test on the internal wiring corresponding to one DC input terminal of the inverter 3. Further, when two voltage dividing modules 22 are provided, the connection point between the two voltage dividing modules 22 can be used as the output terminal DC2+ of the voltage dividing module 22. Among them, a voltage dividing module 22 is connected in series between the output terminal DC2+ and the negative output terminal DC-, and a voltage dividing module 22 is connected in series between the positive output terminal DC+ of the rectification module 21 and the output terminal DC2+, so as to realize the output of test voltages of two voltage levels.

[0052] Figure 3 This is a schematic structural diagram of another inverter anti-misconnection test system provided by an embodiment of the present invention. Refer to Figure 3 , on the basis of the above embodiments, optionally, the main circuit 2 includes: a voltage dividing switch KZ1. The voltage dividing switch KZ1 is connected in series with at least two voltage dividing modules 22 between the positive output terminal DC+ and the negative output terminal DC- of the rectification module 21. The control terminal of the voltage dividing switch KZ1 is connected to the control module 11, and the voltage dividing switch KZ1 is controlled by the control module 11.

[0053] Exemplarily, when the inverter 3 has only one DC input path number, there is no need for the voltage dividing module 22 to divide the voltage. The control module 11 can disconnect the voltage dividing switch KZ1, and the voltage dividing module 22 does not work. The positive output terminal DC+ and the negative output terminal DC- of the rectification module 21 are connected to the inverter 3, and a misconnection test is directly performed. When the inverter 3 has multiple DC input path numbers, the control module 11 can close the voltage dividing switch KZ1, and multiple voltage dividing modules 22 are put into operation. The output terminal of each voltage dividing module 22 is respectively connected to the positive terminal of a DC input terminal of the inverter 3, so as to perform a misconnection test on the internal wiring corresponding to the multiple DC input terminals of the inverter 3.

[0054] Continue to refer to Figure 3 , on the basis of the above embodiments, optionally, the voltage dividing module 22 includes: at least one voltage dividing resistor R connected in series and / or in parallel.

[0055] Among them, the voltage division module 22 realizes voltage division of the direct current output by the rectification module 21 by setting a voltage division resistor R. In a voltage division module 22, one voltage division resistor R can be set, and voltage division is performed by one voltage division resistor R. Multiple voltage division resistors R can also be set. By series-parallel combination of multiple voltage division resistors R, the voltage division module 22 can be set to different resistance values, so as to achieve different voltage divisions. Exemplarily, if the voltage between the positive output terminal DC+ and the negative output terminal DC- of the rectification module 21 is V1 = a(V), then the voltage between the output terminal DC2+ and the negative output terminal DC- of the voltage division module 222 is V2 = R2 / (R1 + R2)×a(V). At this time, the voltage division module 22 inputs test voltages of two voltage levels, V1 and V2, into the inverter 3 respectively.

[0056] Figure 4 The circuit diagram of an anti-misconnection detection circuit for an inverter provided by an embodiment of the present invention. Refer to Figure 4 On the basis of the above embodiments, optionally, the anti-misconnection test system of the inverter further includes: a first power supply line L1, a second power supply line L2, a third power supply line L3, a fourth power supply line L4, and a fifth power supply line L5 for accessing the grid voltage; among them, the first power supply line L1 and the third power supply line L3 access the same grid voltage. The power supply end of the control loop 1 includes: a first live wire end H1 and a neutral wire end N1; the first live wire end H1 is electrically connected to the first power supply line L1, and the neutral wire end N1 is electrically connected to the second power supply line L2. The power supply end of the main loop 2 includes: a first power supply end G1, a second power supply end G2, and a third power supply end G3; the first power supply end G1 is electrically connected to the third power supply line L3, the second power supply end G2 is electrically connected to the fourth power supply line L4, and the third power supply end G3 is electrically connected to the fifth power supply line L5.

[0057] Among them, the first live wire end H1 and the neutral wire end N1 are the power supply ends of the control loop 1, and supply power to the control loop 1 by connecting the first power supply line L1 and the second power supply line L2. The first power supply end G1, the second power supply end G2, and the third power supply end G3 are the power supply ends of the main loop 2, and supply power to the main loop 2 by connecting the third power supply line L3, the fourth power supply line L4, and the fifth power supply line L5. Among them, the first live wire end H1 and the first power supply end G1 share a line, and the same grid voltage can be input to the first power supply line L1 and the third power supply line L3. Exemplarily, the first power supply end G1, the second power supply end G2, the third power supply end G3, and the neutral wire end N1 can be 400V three-phase four-wire alternating current.

[0058] Continue to refer to Figure 4, based on the above embodiments, optionally, the startup module 12 includes: a startup switch SB1, a first relay coil KM1, and a second relay coil KM2. Two first relay contacts km1 are correspondingly arranged for the first relay coil KM1, and three second relay contacts km2 are correspondingly arranged for the second relay coil KM2. The startup switch SB1 and the first relay coil KM1 are connected in series between the first power supply line L1 and the second power supply line L2; the second relay coil KM2 is connected in parallel with the first relay coil KM1. The two first relay contacts km1 are respectively connected in series in the first power supply line L1 and the second power supply line L2. The three second relay contacts km2 are respectively connected in series in the third power supply line L3, the fourth power supply line L4, and the fifth power supply line L5.

[0059] Wherein, when the startup switch SB1 is closed, the first relay coil KM1 and the second relay coil KM2 are powered on, the two first relay contacts km1 are closed, the control circuit 1 is connected, and the control module 11 is powered on. The three second relay contacts km2 are closed, the main circuit 2 is connected, and the rectification module 21 is powered on. The rectification module 21 is controlled by the control module 11, and can convert the three-phase alternating current input from the third power supply line L3, the fourth power supply line L4, and the fifth power supply line L5 into a set direct current, and the positive output terminal DC+ and the negative output terminal DC- of the rectification module 21 are input into the inverter 3. The control module 11 can control the voltage-dividing switch KZ1 to be closed, and by connecting multiple voltage-dividing modules 22, the direct current output by the rectification module 21 is voltage-divided.

[0060] Figure 5 This is the circuit diagram of another anti-misconnection detection circuit for the inverter provided by the embodiment of the present invention. Refer to Figure 5 , based on the above embodiments, optionally, the anti-misconnection detection circuit further includes: a first switch Q1, a second switch Q2, and a third switch Q3. Four first switches Q1 are respectively connected in series in the first power supply terminal G1, the second power supply terminal G2, the third power supply terminal G3, and the neutral line terminal N1. Two second switches Q2 are respectively connected in series in the first power supply line L1 and the second power supply line L2. Three third switches Q3 are respectively connected in series in the third power supply line L3, the fourth power supply line L4, and the fifth power supply line L5.

[0061] Among them, the first switch Q1 is the main switch of the anti-misconnection detection circuit. By closing the first switch Q1, the grid voltage can be input into the first power supply terminal G1, the second power supply terminal G2, the third power supply terminal G3, and the neutral line terminal N1. By closing the second switch Q2, the first power supply line L1 and the second power supply line L2 in the control loop 1 can be energized. By closing the third switch Q3, the third power supply line L3, the fourth power supply line L4, and the fifth power supply line L5 in the main loop 2 can be energized. The first switch Q1 can cut off the anti-misconnection detection circuit when the grid voltage input to the anti-misconnection detection circuit fluctuates, ensuring the stable operation of the anti-misconnection detection circuit. The second switch Q2 can also control the on-off of the control loop 1 and cut off the control loop 1 when the current in the control loop 1 is abnormal, ensuring the safe operation of the control loop 1. The third switch Q3 can also control the on-off of the main loop 2 and cut off the main loop 2 when the current in the main loop 2 is abnormal, ensuring the safe operation of the main loop 2. By setting the first switch Q1, the second switch Q2, and the third switch Q3, the reliability of the anti-misconnection detection circuit can be improved.

[0062] Continue to refer to Figure 5 , based on the above embodiments, optionally, the anti-misconnection detection circuit further includes: an emergency stop switch ES1. The emergency stop switch ES1, the start switch SB1, and the first relay coil KM1 are connected in series. The emergency stop switch ES1 is used to cut off the power supply of the control loop 1 and the main loop 2.

[0063] Among them, the emergency stop switch ES1 can be used to control the on-off of the first relay coil KM1 and the second relay coil KM2. When a fault occurs in the anti-misconnection detection circuit or the inverter 3, or other emergency situations occur, the operator can press the emergency stop button ES1 to cut off the power supply of the first relay coil KM1 and the second relay coil KM2, so that the first relay contact km1 and the second relay contact km2 lose power and disconnect, thereby cutting off the power supply of the main loop 2 and the control loop 1, thus ensuring the safe operation of the anti-misconnection detection circuit.

[0064] Continue to refer to Figure 5 , based on the above embodiments, optionally, the rectification module 21 includes: a photovoltaic simulator U1. The first input terminal of the photovoltaic simulator U1 is connected to the third power supply line L3, the second input terminal of the photovoltaic simulator U1 is connected to the fourth power supply line L4, the third input terminal of the photovoltaic simulator U1 is connected to the fifth power supply line L5, and the positive output terminal and the negative output terminal of the photovoltaic simulator U1 output direct current.

[0065] Among them, since the inverter 3 is a device for converting direct current into alternating current, the alternating current of the main circuit 2 cannot be directly input into the inverter 3. It is necessary to rectify the alternating current into direct current and then input it into the inverter 3. The photovoltaic simulator U1 is a rectifying device. By setting the photovoltaic simulator U1 in the main circuit 2, the alternating current input into the photovoltaic simulator U1 through the line can be rectified into direct current, and then input into the inverter 3. The photovoltaic simulator U1 is controlled by the control module 11 and can adjust the output DC voltage according to the control signal of the control module 11, which has good flexibility.

[0066] Continue to refer to Figure 5 , based on the above embodiments, optionally, the anti-misconnection detection circuit further includes: a cooling fan M1. The cooling fan M1 is connected between the first power supply line L1 and the second power supply line L2. The control end of the cooling fan is connected to the control module 21.

[0067] Among them, since a large amount of heat will be generated when the anti-misconnection detection circuit is running, if the heat cannot be discharged in time, it will inevitably cause the instability of the operation of the main circuit 2 and the control circuit 1. Seriously, it may even burn out the components in the anti-misconnection detection circuit. Therefore, by setting the cooling fan M1, when the anti-misconnection detection circuit is running, the heat in the main circuit 2 and the control circuit 1 can be discharged in time, so as to ensure the stability of the operation of the anti-misconnection detection circuit.

[0068] Based on the above embodiments, optionally, the anti-misconnection test system of the inverter further includes: a host computer. The host computer is connected to the control module 21, and the host computer is used to send instructions to the control module 21. The host computer is also used to receive the voltage collected by the voltage acquisition circuit of the inverter 3.

[0069] Exemplarily, the control module 21 can be a PLC (Programmable Logic Controller), and the host computer can send control instructions to the PLC. For example, when the host computer sends a start instruction to the PLC, the PLC controls the start switch SB1 to close, so that the first relay coil KM1 and the second relay coil KM2 are energized, thereby connecting the main circuit 2 and the control circuit 1. When performing anti-misconnection detection, the host computer can also receive the voltage collected by the voltage acquisition circuit of the inverter 3, and compare this voltage with the test voltage sent by the voltage dividing module 22. If the two voltage values correspond, it means that the wiring is correct, and the host computer displays that the test result passes; if the two voltage values do not correspond, it means that there is a misconnection in the wiring, the host computer displays that the test result fails, and pops up a window to remind the staff to check.

[0070] It should be understood that various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in the present utility model can be executed in parallel, sequentially, or in different orders, as long as the desired results of the technical solution of the present utility model can be achieved, and no limitation is made herein.

[0071] The above specific embodiments do not constitute a limitation on the protection scope of the present utility model. Those skilled in the art should understand that various modifications, combinations, sub - combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. An anti-misconnection test system for an inverter, characterized in that, Including: An anti-misconnection detection circuit and the inverter; the inverter includes at least two DC input paths, and one DC input path corresponds to one DC input terminal; The anti-misconnection detection circuit includes: a control loop and a main loop; The control loop includes a control module and a start module; the control end of the start module is connected to the main loop, and the start module is used to be powered on after receiving a start signal and control the main loop to be powered on; the control module is connected to the main loop and is used to control the output voltage of the main loop; The main loop includes at least two voltage division modules; the voltage division module is used to divide the voltage to output test voltages of different voltage levels; At least two of the DC input terminals of the inverter are respectively electrically connected to at least two of the voltage division modules, and the voltage acquisition circuit of the inverter acquires at least two DC input voltages received by the inverter and generates at least two DC voltage signals according to the at least two DC input voltages.

2. The misconnection prevention test system for an inverter according to claim 1, characterized in that The main loop further includes a rectification module; the output terminals of the rectification module include: a positive output terminal and a negative output terminal; at least two of the voltage division modules are connected in series between the positive output terminal and the negative output terminal of the rectification module; Each of the voltage division modules is provided with an output terminal, and the positive output terminal of the rectification module and the connection points of adjacent two voltage division modules are respectively used as the output terminals of the voltage division modules; the output terminal of each voltage division module is respectively connected to the positive extreme of one of the DC input terminals of the inverter, and the negative output terminal of the rectification module is connected to the negative extreme of the DC input terminal.

3. The anti-misconnection test system for an inverter according to claim 2, characterized in that, The main loop includes: a voltage division switch; The voltage division switch and at least two of the voltage division modules are connected in series between the positive output terminal and the negative output terminal of the rectification module; the control end of the voltage division switch is connected to the control module, and the voltage division switch is controlled by the control module.

4. The misconnection prevention test system of the inverter according to claim 2, characterized in that, The voltage division module includes: at least one voltage division resistor connected in series and / or in parallel.

5. The misconnection prevention test system for an inverter according to claim 2, wherein Also including: A first power supply line, a second power supply line, a third power supply line, a fourth power supply line and a fifth power supply line for accessing the grid voltage; wherein, the first power supply line and the third power supply line access the same grid voltage; The power supply terminal of the control loop includes: a first live wire terminal and a neutral wire terminal; the first live wire terminal is electrically connected to the first power supply line, and the neutral wire terminal is electrically connected to the second power supply line; The power supply terminal of the main loop includes: a first power supply terminal, a second power supply terminal and a third power supply terminal; the first power supply terminal is electrically connected to the third power supply line, the second power supply terminal is electrically connected to the fourth power supply line, and the third power supply terminal is electrically connected to the fifth power supply line.

6. The anti-misconnection test system for an inverter according to claim 5, characterized in that, The start module includes: a start switch, a first relay coil and a second relay coil; two first relay contacts are correspondingly arranged for the first relay coil, and three second relay contacts are correspondingly arranged for the second relay coil; The start switch and the first relay coil are connected in series between the first power supply line and the second power supply line; the second relay coil is connected in parallel with the first relay coil; The two first relay contacts are respectively connected in series in the first power supply line and the second power supply line; the three second relay contacts are respectively connected in series in the third power supply line, the fourth power supply line and the fifth power supply line.

7. The anti-misconnection test system for an inverter according to claim 5, characterized in that, The anti-misconnection detection circuit further includes: a first switch, a second switch and a third switch; The four first switches are respectively connected in series in the first power supply terminal, the second power supply terminal, the third power supply terminal and the neutral line terminal; The two second switches are respectively connected in series in the first power supply line and the second power supply line; The three third switches are respectively connected in series in the third power supply line, the fourth power supply line and the fifth power supply line.

8. The misconnection prevention test system for an inverter according to claim 6, wherein, The anti-misconnection detection circuit further includes: an emergency stop switch; The emergency stop switch, the start switch and the first relay coil are connected in series; the emergency stop switch is used to cut off the power supply of the control circuit and the main circuit.

9. The anti-misconnection test system for an inverter according to claim 5, characterized in that The rectification module includes: a photovoltaic simulator; The first input terminal of the photovoltaic simulator is connected to the third power supply line, the second input terminal of the photovoltaic simulator is connected to the fourth power supply line, the third input terminal of the photovoltaic simulator is connected to the fifth power supply line, and the positive output terminal and the negative output terminal of the photovoltaic simulator output direct current.

10. The anti-misconnection test system for an inverter according to claim 5, characterized in that, The anti-misconnection detection circuit further includes: a cooling fan; The cooling fan is connected between the first power supply line and the second power supply line; the control terminal of the cooling fan is connected to the control module.

11. The anti-misconnection test system of the inverter according to claim 1, characterized in that, It further includes: A host computer; The host computer is connected to the control module, and the host computer is used to send instructions to the control module; the host computer is further used to receive the voltage collected by the voltage acquisition circuit of the inverter.

Images