A communication collection device, photovoltaic inverter and control system

Abstract

A communication collection device, a photovoltaic inverter and a control system, wherein the communication collection device comprises: a first communication module for receiving the output voltage transmitted by the component control end and sending the component on / off signal to the component control end; a second communication module for receiving the group string on / off signal sent by the monitoring end and transmitting the loop current and output voltage to the monitoring end; a microcontroller for receiving the loop current collected by the inverter body; the microcontroller is also connected to the first communication module and the second communication module respectively, and is used to receive the output voltage and send the component on / off signal to the component control end through the first communication module, and receive the group string on / off signal transmitted by the monitoring end through the second communication module and transmit the loop current and output voltage to the monitoring end. The embodiment of the present invention not only realizes remote monitoring of the status of photovoltaic components, but also has the ability to remotely shut down the photovoltaic components, which not only integrates the two major functions, but also greatly reduces the cost of monitoring.

Description

Technical Field

[0001] The present invention belongs to the field of photovoltaic power generation, and in particular relates to a communication collection device, a photovoltaic inverter and a control system. Background Art

[0002] With the development and maturity of photovoltaic power generation technology, photovoltaic power generation has become one of the important components in the field of new energy.

[0003] At present, in the photovoltaic industry, the photovoltaic inverters produced by mainstream photovoltaic inverter manufacturers are all string inverters. These string inverters can only realize string-level monitoring, but cannot realize monitoring of the photovoltaic module level. These string inverters can only monitor the voltage and current of the photovoltaic strings, and these string inverters themselves cannot communicate with the module control end of the photovoltaic module level. Therefore, the existing inverter technology can only realize string-level monitoring, but not module-level monitoring, and it is even more impossible to control the underlying equipment where the photovoltaic module is located.

[0004] Professional terms: Photovoltaic module: A power generation device that converts solar energy into direct current, also called a solar panel. Photovoltaic string: In a photovoltaic power generation system, a circuit unit composed of several or even dozens of photovoltaic modules connected in series. DC high voltage: In a photovoltaic power generation system composed of several or even dozens of photovoltaic modules connected in series, there is a DC high voltage of 500V to 1500V. Photovoltaic inverter: A device that converts the DC power generated by a photovoltaic module into an AC output. Summary of the invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a communication collection device, which has a simple structure and solves the problem that the photovoltaic inverter cannot perform photovoltaic module level monitoring. The present invention also proposes a photovoltaic inverter and a photovoltaic module control system.

[0006] According to the first aspect of the present invention, the communication collection device comprises: a first communication module, which is used to connect to the component control end of the photovoltaic component; the component control end is used to collect the output voltage of the photovoltaic component and output it to the first communication module, and control the on and off of the photovoltaic component according to the component on and off signal output by the first communication module; a second communication module, which is used to receive the group string on and off signal sent by the monitoring end and transmit the loop current and the output voltage to the monitoring end; a microcontroller, which is used to connect to the inverter body connected in series with the photovoltaic string and receive the loop current collected by the inverter body; the microcontroller is also connected to the first communication module and the second communication module respectively, and is used to receive the output voltage and send the component on and off signal to the component control end through the first communication module, and is also used to receive the group string on and off signal transmitted by the monitoring end through the second communication module and transmit the loop current and output voltage to the monitoring end.

[0007] According to the communication collection device of the embodiment of the present invention, at least the following technical effects are achieved: the communication with the underlying component control end is realized through the first communication module, and the voltage data of the photovoltaic component collected by the component control end can be received and uploaded to the monitoring end through the second communication module, thereby realizing the monitoring of the photovoltaic component level; at the same time, the microcontroller can send the component on-off signal to the component control end through the first communication module, and control the component control end to turn off the component off switch connected to the photovoltaic component, thereby realizing the off control of the photovoltaic component level. The microcontroller can obtain the loop current of the photovoltaic string collected by the inverter body through communication with the inverter body, and then cleverly use the characteristics of equal loop current to obtain the current of the photovoltaic components in the photovoltaic string, which can effectively reduce the repeated arrangement of current sensors in the photovoltaic power generation field and greatly reduce the cost. In addition, the microcontroller can control the inverter body to turn off the current switch of the inverter body itself, so that the loop of the photovoltaic string is disconnected, so that the component control end can no longer face the impact of large current when the component off switch is turned off later.

[0008] According to some embodiments of the present invention, the first communication module and / or the second communication module is a wireless communication module.

[0009] According to some embodiments of the present invention, the wireless communication module adopts a WIFI module, a Bluetooth module or a ZigBee module.

[0010] According to some embodiments of the present invention, the second communication module is a GSM / GPRS module.

[0011] According to some embodiments of the present invention, the first communication module adopts a power line carrier communication module.

[0012] According to some embodiments of the present invention, the microcontroller employs a processor having an internal temperature sensor.

[0013] According to some embodiments of the present invention, the communication and data collection device further includes a temperature collection unit connected to the microcontroller, and the temperature collection unit is used to collect the temperature of the inverter body.

[0014] A photovoltaic inverter according to an embodiment of the second aspect of the present invention includes an inverter body and the above-mentioned communication collection device connected to the inverter body.

[0015] The photovoltaic inverter according to the embodiment of the present invention has at least the following technical effects: by adding a communication collection device to the traditional inverter body, it can have the ability to interact with the underlying component control end data, can realize the collection of photovoltaic component voltage data, can realize the control of whether the photovoltaic component is connected to the photovoltaic string, and at the same time can also make the means of communication with the monitoring end more diversified, thereby improving the stability of communication.

[0016] According to the third aspect of the present invention, a photovoltaic component control system includes: the above-mentioned photovoltaic inverter; a component control end, connected to the photovoltaic inverter, used to collect the output voltage of the photovoltaic component and transmit it to the photovoltaic inverter, and also used to receive the component on-off signal sent by the photovoltaic inverter to control the on-off of the photovoltaic component; a monitoring end, connected to the photovoltaic inverter, used to send the group string on-off signal to the photovoltaic inverter, and also used to receive the output voltage and loop current sent by the photovoltaic inverter.

[0017] The photovoltaic module control system according to the embodiment of the present invention has at least the following technical effects: by adding the photovoltaic inverter in the embodiment of the present invention, it is possible to truly realize data monitoring of the photovoltaic module at the monitoring end, and also have the ability to remotely shut down the photovoltaic module. At the same time, collecting current through the photovoltaic inverter can greatly reduce the cost of monitoring the entire photovoltaic power generation system, and there is no need to repeatedly arrange the current collection unit for each photovoltaic module. In addition, through the embodiment of the present invention, the photovoltaic inverter can first shut down its own current switch, which can effectively avoid the subsequent shutdown of the large current impact faced by the component shutdown switch, so that the component shutdown switch can use a miniaturized, low-cost switch, further reducing the cost.

[0018] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0020] Figure 1is a schematic diagram of the principle of a photovoltaic inverter according to an embodiment of the present invention;

[0021] Figure 2 is a system block diagram of a photovoltaic assembly control system according to an embodiment of the present invention;

[0022] Figure 3 1 is a schematic diagram of the temperature acquisition unit according to an embodiment of the present invention.

[0023] Reference numerals:

[0024] The first communication module 100,

[0025] The second communication module 200,

[0026] Microcontroller 300,

[0027] Component control terminal 400,

[0028] Monitoring terminal 500,

[0029] Inverter body 600,

[0030] The component turns off the switch 700 . DETAILED DESCRIPTION

[0031] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0032] In the description of the present invention, if there is a description of first, second, third, fourth, etc., it is only for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the sequence of the indicated technical features.

[0033] In the description of the present invention, unless otherwise clearly defined, words such as setting and connecting should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above words in the present invention in combination with the specific content of the technical solution.

[0034] Reference below Figures 1 to 3 A communication collection device according to an embodiment of the first aspect of the present invention is described.

[0035] The communication collection device according to the embodiment of the present invention includes: a first communication module 100 , a second communication module 200 , and a microcontroller 300 . The first communication module 100 is used to connect to the component control terminal 400 of the photovoltaic component; the component control terminal 400 is used to collect the output voltage of the photovoltaic component and output it to the first communication module 100, and control the on and off of the photovoltaic component according to the component on and off signal output by the first communication module 100; the second communication module 200 is used to receive the group string on and off signal sent by the monitoring terminal 500 and transmit the loop current and output voltage to the monitoring terminal 500; the microcontroller 300 is used to connect to the inverter body 600 connected in series with the photovoltaic string and receive the loop current collected by the inverter body 600; the microcontroller 300 is also connected to the first communication module 100 and the second communication module 200 respectively, and is used to receive the output voltage and send the component on and off signal to the component control terminal 400 through the first communication module 100, and is also used to receive the group string on and off signal transmitted by the monitoring terminal 500 through the second communication module 200 and transmit the loop current and output voltage to the monitoring terminal 500.

[0036] refer to Figure 1 , Figure 2 , the microcontroller 300 exchanges data with the component control terminal 400 through the first communication module 100. The component control terminal 400 is used to collect voltage data, temperature data, etc. of the photovoltaic component. The data collected by the component control terminal 400 will be sent to the first communication module 100, and the first communication module 100 will be transmitted to the microcontroller 300. In the existing photovoltaic power generation system, the inverter body 600 connected in series with the photovoltaic string itself has the function of current collection. The microcontroller 300 can obtain the loop current of the photovoltaic string collected by the inverter body 600 by communicating with the inverter body 600. Because the current is equal everywhere in the loop current, the current of the photovoltaic components in the photovoltaic string is also equal, which is also a disguised way to obtain the current data of the photovoltaic component. Then, the monitoring terminal 500 sent by the second communication module 200 can realize photovoltaic component-level monitoring.

[0037] refer to Figure 1 , Figure 2, for realizing the component-level shutdown function, there is no need to add a separate shutdown control system, and the microcontroller 300 and the first communication module 100 can be directly used to control the component control terminal 400, and the component control terminal 400 can complete the control of the component shutdown switch 700 according to the component on-off signal sent by the microcontroller 300. Here is a brief description of the photovoltaic component shutdown process: the monitoring terminal 500 sends a group string on-off signal, and the second communication module 200 receives the group string on-off signal and transmits it to the microcontroller 300. The microcontroller 300 controls the inverter body 600 to turn off the current switch of the inverter body 600 itself. After the shutdown is completed, the microcontroller 300 sends a component on-off signal to the component control terminal 400, and the component control terminal 400 controls the component shutdown switch 700 to turn off.

[0038] In addition, it should be noted that the microcontroller 300 first controls the inverter body 600 to turn off the current switch of the inverter body 600 itself, so as to ensure that the photovoltaic string circuit is disconnected, and then the subsequent component shutdown switch 700 no longer needs to face the impact of large current when it is turned off. Therefore, the component shutdown switch 700 can choose a switch with small size, low cost, and no need to withstand large current surges.

[0039] According to the communication collection device of the embodiment of the present invention, the communication with the bottom component control terminal 400 is realized through the first communication module 100, and the voltage data of the photovoltaic component collected by the component control terminal 400 can be received and uploaded to the monitoring terminal 500 through the second communication module 200, thereby realizing the monitoring of the photovoltaic component level; at the same time, the microcontroller 300 can send a component on-off signal to the component control terminal 400 through the first communication module 100, and control the component control terminal 400 to turn off the component off switch 700 connected to the photovoltaic component, thereby realizing the on and off control of the photovoltaic component level. The microcontroller 300 can obtain the loop current of the photovoltaic string collected by the inverter body 600 through communication with the inverter body 600, and then cleverly use the characteristics of equal loop current to know the current of the photovoltaic component in the photovoltaic string, which can effectively reduce the arrangement of current sensors in the photovoltaic power generation field. In addition, the microcontroller 300 can control the inverter body 600 to turn off the current switch of the inverter body 600 itself, so as to disconnect the circuit of the photovoltaic string, so that the component control end 400 will no longer face the impact of large current when the component shutdown switch 700 is subsequently turned off.

[0040] In some embodiments of the present invention, the first communication module 100 and / or the second communication module 200 adopt a wireless communication module. Data transmission through wireless communication can greatly reduce the number of communication lines in the photovoltaic power generation system, and because the photovoltaic power generation system itself is in a relatively open environment, there is less interference during wireless communication, and the distance of wireless transmission can be effectively guaranteed, thereby effectively controlling the cost of wireless communication. Compared with the traditional wired communication method, it can control the increase in cost and reduce on-site wiring, thereby improving the safety and stability of the entire photovoltaic power generation system.

[0041] In some embodiments of the present invention, the wireless communication module uses a WIFI module, a Bluetooth module or a ZigBee module. There are many ways of wireless communication, and wireless transmission methods such as WIFI, Bluetooth, and ZigBee can be selected for communication according to the use requirements and the size of the site. In some embodiments of the present invention, the wireless communication module chooses to use a ZigBee module for communication. The ZigBee module is cheap and has a long communication distance, which is sufficient to meet the needs of most photovoltaic power generation systems.

[0042] In some embodiments of the present invention, the second communication module 200 uses a GSM / GPRS module. After using the GSM / GPRS module, ultra-long-distance wireless communication can be achieved by means of a built-in SIM card, and data transmission can be directly completed using an existing mobile base station, without the need to arrange another wireless communication system to achieve ultra-long-distance wireless communication.

[0043] In some embodiments of the present invention, the first communication module 100 adopts a power line carrier communication module. By communicating through a power line carrier, the existing lines are directly used for data communication, which can effectively reduce wiring. At the same time, compared with wireless communication, the impact of electromagnetic waves can also be reduced.

[0044] In some embodiments of the present invention, the microcontroller 300 uses a processor with an internal temperature sensor. The temperature of the inverter body 600 can be detected by the internal temperature sensor. The temperature of the inverter body 600 can effectively feedback the working state of the inverter body 600 to a certain extent. When the temperature of the inverter body 600 rises sharply or the temperature of the inverter body 600 exceeds the normal temperature, an alarm can be sent to the monitoring terminal 500 in time.

[0045] In some embodiments of the present invention, the microcontroller 300 uses an MSP430 series single-chip microcomputer. The internal temperature sensor of the MSP430 series single-chip microcomputer has relatively accurate data acquisition and low cost, and is suitable for large-scale applications.

[0046] In some embodiments of the present invention, the communication acquisition device further includes a temperature acquisition unit connected to the microcontroller 300, and the temperature acquisition unit is used to acquire the temperature of the inverter body 600. By adding an external temperature acquisition unit, a part of the microcontroller 300 that does not have an internal temperature sensor can also be used for temperature acquisition. At the same time, by adding an external temperature acquisition unit, the location of temperature acquisition can be made more flexible, and the collected temperature data can be relatively more accurate. In some embodiments of the present invention, the temperature acquisition unit directly uses an existing temperature acquisition module.

[0047] In some embodiments of the present invention, the temperature acquisition unit uses a resistive temperature sensor for temperature acquisition. The resistive temperature sensor is relatively low in cost, which can further reduce the cost and facilitate subsequent replacement. When the temperature acquisition unit uses a resistive temperature sensor for temperature acquisition, its application circuit can refer to Figure 3 , the temperature data can be directly and effectively fed back through the voltage divider circuit, and after being isolated and protected by the voltage follower and the clamp protection circuit, it is input to the microcontroller 300. The resistor R1 can be a variable resistor, which can improve the application range of the temperature acquisition unit. In addition, some components in the circuit may have slight errors due to aging, and the errors can also be corrected by adjusting the variable resistor to further extend the service life. In addition, the temperature acquisition unit can be connected to the ADC port of the microcontroller 300 to realize the transmission of temperature data.

[0048] The photovoltaic inverter according to the second embodiment of the present invention includes an inverter body 600 and the above-mentioned communication collection device connected to the inverter body 600 .

[0049] The photovoltaic inverter according to the embodiment of the present invention can have the ability to communicate with the underlying component control terminal 400 by adding a communication collection device to the traditional inverter body 600, can realize the collection of photovoltaic component voltage data, can realize the control of whether the photovoltaic component is connected to the photovoltaic string, and can also make the means of communication with the monitoring terminal 500 more diversified, thereby improving the stability of communication.

[0050] According to the photovoltaic module control system of the embodiment of the third aspect of the present invention, it includes the above-mentioned photovoltaic inverter, module control terminal 400, and monitoring terminal 500; the module control terminal 400 is connected to the photovoltaic inverter, and is used to collect the output voltage of the photovoltaic module and transmit it to the photovoltaic inverter, and is also used to receive the module on-off signal sent by the photovoltaic inverter and control the on-off of the photovoltaic module; the monitoring terminal 500 is connected to the photovoltaic inverter, and is used to send the group string on-off signal to the photovoltaic inverter, and is also used to receive the output voltage and loop current sent by the photovoltaic inverter.

[0051] refer to Figure 2, the photovoltaic string will be connected in series with a photovoltaic inverter, and the photovoltaic inverter will convert direct current into alternating current. Referring to the foregoing, the photovoltaic inverter in some embodiments of the present invention includes an inverter body 600 and a communication collection device. The loop current of the photovoltaic string can be directly known by exchanging data with the inverter body 600 through the communication collection device; the output voltage transmitted by the component control terminal 400 can also be received through the communication collection device; and then the output voltage and loop current data are transmitted to the monitoring terminal 500 through the communication collection device. When the photovoltaic component needs to be shut down, the monitoring terminal 500 sends a string on-off signal to the communication collection device, and the communication collection device controls the inverter body 600 to shut down the current switch of the inverter body 600 itself, so as to realize the power-off of the entire photovoltaic string loop, and then the communication collection device sends a component on-off signal to the component control terminal 400, and the component control terminal 400 controls the component shut-off switch 700 to be disconnected.

[0052] According to the photovoltaic module control system of the embodiment of the present invention, by adding the photovoltaic inverter in the embodiment of the present invention, it is possible to truly realize the data monitoring of the first level of the photovoltaic module at the monitoring end 500, and it is also capable of remotely shutting down the photovoltaic module. At the same time, collecting current through the photovoltaic inverter can greatly reduce the cost of monitoring the entire photovoltaic power generation system, and it is no longer necessary to arrange a current collection unit for each photovoltaic module. In addition, by first turning off its own current switch through the photovoltaic inverter in the embodiment of the present invention, the large current impact faced by the subsequent shutdown of the component shutdown switch 700 can be effectively avoided, so that the component shutdown switch 700 can be miniaturized, further reducing the cost.

[0053] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0054] Although the embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, the present invention is not limited to the above embodiments. Those skilled in the art will understand that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and purpose of the present invention. The scope of the present invention is defined by the claims and their equivalents.

Claims

1. A communication collection device, characterized in that: include: A first communication module (100) is used to connect to a component control terminal (400) of a photovoltaic component; the component control terminal (400) is used to collect the output voltage of the photovoltaic component and output it to the first communication module (100), and to control the on / off of the photovoltaic component according to the component on / off signal output by the first communication module (100); A second communication module (200) is used to receive a string on / off signal sent by the monitoring terminal (500) and transmit the loop current and the output voltage to the monitoring terminal (500); The microcontroller (300) is used to connect to the inverter body (600) and receive the loop current collected by the inverter body (600); the microcontroller (300) is also connected to the first communication module (100) and the second communication module (200) respectively, and is used to receive the output voltage through the first communication module (100) and send the component on / off signal to the component control terminal (400), and is also used to receive the group string on / off signal transmitted by the monitoring terminal (500) through the second communication module (200) and transmit the loop current and output voltage to the monitoring terminal (500).

2. The communication collection device according to claim 1, characterized in that: The first communication module (100) and / or the second communication module (200) are wireless communication modules.

3. The communication collection device according to claim 2, characterized in that: The wireless communication module adopts a WIFI module, a Bluetooth module or a ZigBee module.

4. The communication collection device according to claim 1, characterized in that: The second communication module (200) adopts a GSM / GPRS module.

5. The communication collection device according to claim 1, characterized in that: The first communication module (100) adopts a power line carrier communication module.

6. The communication collection device according to claim 1, characterized in that: The microcontroller (300) uses a processor with an internal temperature sensor.

7. The communication collection device according to claim 1, characterized in that: It also includes a temperature collection unit connected to the microcontroller (300), and the temperature collection unit is used to collect the temperature of the inverter body (600).

8. A photovoltaic inverter, characterized in that: It comprises an inverter body (600) and a communication collection device according to any one of claims 1 to 7 connected to the inverter body (600).

9. A photovoltaic module control system, characterized in that include: The photovoltaic inverter according to claim 8; A component control terminal (400) is connected to the photovoltaic inverter, used to collect the output voltage of the photovoltaic component and transmit it to the photovoltaic inverter, and also used to receive the component on / off signal sent by the photovoltaic inverter to control the on / off of the photovoltaic component; The monitoring terminal (500) is connected to the photovoltaic inverter and is used to send the string on / off signal to the photovoltaic inverter, and is also used to receive the output voltage and loop current sent by the photovoltaic inverter.

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