Photovoltaic inverter interface expansion conversion circuit

Abstract

The utility model provides a photovoltaic inverter interface expansion conversion circuit. The photovoltaic inverter interface expansion conversion circuit comprises a main control chip, an RS485 slave, a first RS485 host, a second RS485 host, a digital isolator, a photovoltaic inverter access end, an inverter data disassembly rod access end and a collector data input end. The photovoltaic inverter access end comprises a power supply input end and an RS485 slave interface; the inverter data disassembly rod access end comprises a power supply output end and a first RS485 host interface; the data input end of the collector comprises a second RS485 host interface; the input end of the RS485 slave is connected with the RS485 slave interface, the output end of the RS485 slave is connected with the input end of the digital isolator, and the output end of the digital isolator is connected with the main control chip. According to the scheme, two channels are supported to realize simultaneous communication without mutual influence by adopting hardware isolation and matching with program software.

Description

Technical Field

[0001] This utility model relates to the field of photovoltaic inverter interface expansion technology, and in particular to photovoltaic inverter interface expansion conversion circuit. Background Technology

[0002] Currently, most manufacturers of deployed residential distributed photovoltaic inverters only have one RS485 communication serial port. This RS485 serial port is used by the inverter manufacturer for communication and data collection via a data monitoring stick. This monitoring stick provides users with accurate and comprehensive data analysis and timely and effective fault alarms. However, after using this data monitoring stick, the fusion terminal cannot communicate with this communication serial port, and the data collection by the power company and the user manufacturer's cloud master station cannot be carried out simultaneously. Utility Model Content

[0003] In view of this, the purpose of this utility model is to provide a photovoltaic inverter interface expansion conversion circuit that supports two channels to communicate simultaneously without interference, using hardware isolation and software.

[0004] To achieve the above objectives, this utility model adopts the following technical solution: a photovoltaic inverter interface expansion conversion circuit, including a master control chip, an RS485 slave, a first RS485 master, a second RS485 master, a digital isolator, a photovoltaic inverter access terminal, an inverter data disconnection stick access terminal, and a data acquisition unit input terminal; the photovoltaic inverter access terminal includes a power input terminal and an RS485 slave interface; the inverter data disconnection stick access terminal includes a power output terminal and a first RS485 master interface; the data acquisition unit input terminal includes a second RS485 master interface; the input terminal of the RS485 slave is connected to the RS485 slave interface, the output terminal of the RS485 slave is connected to the input terminal of the digital isolator, and the output terminal of the digital isolator is connected to the master control chip; the input terminal of the first RS485 master is connected to the master control chip, and the output terminal of the first RS485 master is connected to the first RS485 master interface; the input terminal of the second RS485 master is connected to the master control chip, and the output terminal of the second RS485 master is connected to the second RS485 master interface.

[0005] In a preferred embodiment, the system further includes a first light-emitting diode, a second light-emitting diode, a third light-emitting diode, and a fourth light-emitting diode; the positive terminals of the first light-emitting diode, the second light-emitting diode, the third light-emitting diode, and the fourth light-emitting diode are all connected to the main control chip, and the negative terminals of the first light-emitting diode, the second light-emitting diode, the third light-emitting diode, and the fourth light-emitting diode are all grounded.

[0006] In a preferred embodiment, the system further includes a DC-DC converter; the input of the DC-DC converter is connected to the power input, and the output of the DC-DC converter is connected to a digital isolator and the positive terminal of a first light-emitting diode.

[0007] In a preferred embodiment, the second light-emitting diode is used for slave data communication status indication.

[0008] In a preferred embodiment, the third light-emitting diode is used as a first RS485 host data communication status indicator.

[0009] In a preferred embodiment, the fourth light-emitting diode is used as a second RS485 host data communication status indicator.

[0010] Compared with existing technologies, this utility model has the following advantages: It solves the problem of communication multiplexing technology in distributed photovoltaic inverters. Based on a plug-and-play expansion module, the module draws its own power from the inverter's communication interface, enabling the integrated distribution terminal and the photovoltaic communication stick to simultaneously access the photovoltaic inverter's serial port. It has a built-in large-capacity communication buffer, supporting multiple RS485 communication ports to simultaneously access the photovoltaic inverter's communication port, and supports Modbus multi-master-one-slave communication functionality. The module is small in size, easy to install, and the communication interface is freely configurable, compatible with the communication interfaces of all mainstream photovoltaic inverter manufacturers on the market. Attached Figure Description

[0011] Figure 1 This is a circuit connection diagram of a preferred embodiment of the present invention. Detailed Implementation

[0012] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0013] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0014] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations according to this application; as used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise; furthermore, it should be understood that when the terms “comprising” and / or “including” are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0015] Photovoltaic inverter interface expansion conversion circuit, reference Figure 1The system includes a main control chip (MCU), an RS485 slave device (S), a first RS485 master device (M-1), a second RS485 master device (M-2), a digital isolator, a photovoltaic inverter access terminal, an inverter data disconnection stick access terminal, and a data acquisition device input terminal. The photovoltaic inverter access terminal includes a power input terminal and an RS485 slave interface. The inverter data disconnection stick access terminal includes a power output terminal and a first RS485 master interface. The data acquisition device input terminal includes a second RS485 master interface. The input terminal of the RS485 slave device (S) is connected to the RS485 slave interface, and the output terminal of the RS485 slave device (S) is connected to the input terminal of the digital isolator. The output terminal of the digital isolator is connected to the main control chip. The input terminal of the first RS485 master device (M-1) is connected to the main control chip, and the output terminal of the first RS485 master device (M-1) is connected to the first RS485 master interface. The input terminal of the second RS485 master device (M-2) is connected to the main control chip, and the output terminal of the second RS485 master device (M-2) is connected to the second RS485 master interface. The RS485 slave device S and the first RS485 master device M-1 and the second RS485 master device M-2 can achieve data transmission between the master and slave ports after interface conversion by the main control chip. The MCU supports data buffering, which can avoid data conflicts and errors when data is collected from the two master ports at the same time.

[0016] In this embodiment, a first light-emitting diode, a second light-emitting diode, a third light-emitting diode, and a fourth light-emitting diode are also included; the positive terminals of the first light-emitting diode, the second light-emitting diode, the third light-emitting diode, and the fourth light-emitting diode are all connected to the main control chip MCU, and the negative terminals of the first light-emitting diode, the second light-emitting diode, the third light-emitting diode, and the fourth light-emitting diode are all grounded.

[0017] In this embodiment, a DC-DC converter is also included; the input terminal of the DC-DC converter is connected to the power input terminal, and the output terminal of the DC-DC converter is connected to the digital isolator and the positive terminal of the first light-emitting diode; the first light-emitting diode serves as a power indicator light, and the light being on indicates that the power supply has been connected.

[0018] In this embodiment, the second light-emitting diode is used to indicate the data communication status of the slave device S.

[0019] In this embodiment, the third light-emitting diode is used to indicate the data communication status of the first RS485 host M-1.

[0020] In this embodiment, the fourth light-emitting diode is used to indicate the M-2 data communication status of the second RS485 host.

[0021] The second, third, and fourth LEDs are all directly controlled by the main control chip MCU. When there is data communication at the relevant port, the corresponding indicator light will be lit.

Claims

1. Photovoltaic inverter interface extension conversion circuit, characterized in that, The application relates to a photovoltaic inverter data acquisition device, which comprises a master control chip, an RS485 slave machine, a first RS485 master machine, a second RS485 master machine, a digital isolator, a photovoltaic inverter access end, an inverter data disassembly rod access end and a collector data input end; the photovoltaic inverter access end comprises a power input end and an RS485 slave machine interface; the inverter data disassembly rod access end comprises a power output end and a first RS485 master machine interface; the collector data input end comprises a second RS485 master machine interface; the input end of the RS485 slave machine is connected with the RS485 slave machine interface, the output end of the RS485 slave machine is connected with the input end of the digital isolator, and the output end of the digital isolator is connected with the master control chip; the input end of the first RS485 master machine is connected with the master control chip, and the output end of the first RS485 master machine is connected with the first RS485 master machine interface; the input end of the second RS485 master machine is connected with the master control chip, and the output end of the second RS485 master machine is connected with the second RS485 master machine interface.

2. The photovoltaic inverter interface extension conversion circuit according to claim 1, characterized in that, The application further comprises a first light emitting diode, a second light emitting diode, a third light emitting diode and a fourth light emitting diode; the positive poles of the first light emitting diode, the second light emitting diode, the third light emitting diode and the fourth light emitting diode are connected with the master control chip, and the negative poles of the first light emitting diode, the second light emitting diode, the third light emitting diode and the fourth light emitting diode are grounded.

3. The photovoltaic inverter interface extension conversion circuit of claim 2, wherein, The application further comprises a DC-DC converter; the input end of the DC-DC converter is connected with the power input end, and the output end of the DC-DC converter is connected with the digital isolator and the positive pole of the first light emitting diode.

4. The photovoltaic inverter interface extension conversion circuit of claim 2, wherein, The second light emitting diode is used for indicating the data communication state of the slave machine.

5. The photovoltaic inverter interface extension conversion circuit of claim 2, wherein, The third light emitting diode is used for indicating the data communication state of the first RS485 master machine.

6. The photovoltaic inverter interface extension conversion circuit of claim 2, wherein, The fourth light emitting diode is used for indicating the data communication state of the second RS485 master machine.

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