Photovoltaic protocol converter based on power line carrier communication technology

Abstract

The invention discloses a photovoltaic protocol converter based on a power line carrier communication technology. The photovoltaic protocol converter comprises a power line carrier chip, a power supply filter circuit, a carrier coupling circuit, a zero-crossing circuit, a power amplification circuit, a main control chip circuit, a 485 circuit, a clock circuit, a level conversion circuit, a wireless communication circuit, an ESAM circuit and a FLASH circuit. The 485 circuit is connected with an external inverter to obtain inverter information and perform information interaction, and the main control unit circuit transmits the information to a single-phase dual-mode module through a carrier module interface after obtaining the information. The photovoltaic protocol converter can collect, process and monitor power generation and power utilization information of a photovoltaic user in real time, information monitoring of photovoltaic power generation is improved, the user is safer and more reliable in the power utilization process, and the problem that information collection cannot be implemented in a traditional photovoltaic power supply system is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of photovoltaic power communication, and in particular to a photovoltaic protocol converter based on power line carrier communication technology. Background Art

[0002] Photovoltaic power generation system is a new type of power generation system that uses the photovoltaic effect of solar cell semiconductor materials to directly convert solar radiation energy into electrical energy. With the development of science and technology, photovoltaic power can be seen everywhere in daily life, playing an extremely important role in street lighting, photovoltaic energy storage, household solar energy systems, etc. Complex photovoltaic systems can be incorporated into the power grid system for power supply. The application of photovoltaic power not only greatly reduces environmental pollution, but also reduces household electricity consumption, playing an important role in improving the environment.

[0003] Power line carrier communication technology is a kind of power system communication that uses transmission lines as carrier signal transmission medium. Since the transmission line has a very solid support structure and is equipped with more than three conductors (generally three-phase good conductors and one or two overhead ground wires), the transmission line is used to transmit carrier signals while transmitting industrial frequency current, which is both economical and very reliable. This comprehensive utilization has become a unique communication method preferred by most power departments. By combining power line carrier communication technology with photovoltaic power generation systems, it can not only reduce costs, improve communication convenience and reliability, but also be widely used in photovoltaic power systems.

[0004] In the field of photovoltaic power systems, research on practical scenarios of high efficiency, low cost, and large-scale applications is the current frontier and important development direction of photovoltaic power generation. However, in actual applications, it is found that solar energy is greatly affected by changes in the weather, which leads to the fact that the power system has been in an unstable state during the all-weather photovoltaic power generation and electricity consumption process. This unstable state seriously restricts the use of photovoltaic energy. Photovoltaic protocol converters can solve such instability problems, but the functions of photovoltaic protocol converters on the market are relatively simple. Most of them only read and transmit the information of the inverter through the connection with the inverter. The deployment and detection of power quality are not involved, and the monitorability is not strong, and the upgrade speed is slow. Summary of the invention

[0005] To this end, the present invention proposes a photovoltaic protocol converter based on power line carrier communication technology, which can collect, process and monitor the power generation and power consumption information of photovoltaic users in real time, improve the information monitoring of photovoltaic power generation, make the user's use of electricity safer and more reliable, and solve the above-mentioned problems existing in the photovoltaic protocol converters currently used in the power supply system.

[0006] A photovoltaic protocol converter based on power line carrier communication technology, comprising: a power carrier chip, a power filter circuit, a carrier coupling circuit, a zero-crossing circuit, a power amplifier circuit, a main control chip circuit, a 485 circuit, a clock circuit and a level conversion circuit; the power carrier chip modulates and demodulates the carrier signal through the carrier coupling circuit, and realizes data transmission and at least one connection with a power concentrator through the power line; the power filter circuit provides a working voltage for the photovoltaic protocol converter by filtering the input power; the carrier coupling circuit is used to transmit the input information received by the power carrier to the power carrier chip through carrier coupling, and transmit the output information of the power carrier sent by the power carrier chip to the slave information processing device through carrier coupling and power line; the zero-crossing circuit transmits information by judging that the power line is at a zero-crossing point; the power amplifier circuit is used to transmit the power carrier chip to the power carrier chip through the carrier coupling circuit. After the signal output by the chip is amplified, it is loaded onto the power line through the carrier coupling circuit and transmitted to the slave information processing device; the main control chip circuit is used to process the information transmitted by the 485 circuit, and then transmit the processed information to the external connection device through the 485 circuit, and is also used to transmit the information to the power carrier chip through the level conversion circuit, and then the carrier coupling circuit transmits the output information to the information processing device; the 485 circuit is used to transmit the information of the external inverter to the main control chip circuit, and at the same time transmit the control command of the main control chip circuit back to the external inverter for interaction; the clock circuit is used to store device time and transmit information to the information processing device through the main control chip circuit; the level conversion circuit is used to perform level conversion on the serial port signal between the main control chip circuit and the power carrier chip, playing the role of level conversion and protection circuit.

[0007] Furthermore, the power carrier chip transmits the output information to the power grid concentrator through the carrier coupling circuit.

[0008] Furthermore, it also includes: a wireless communication circuit connected to the main control chip circuit, and used for remotely upgrading the main control chip circuit.

[0009] Furthermore, it also includes: an ESAM circuit, connected to the main control chip circuit, for encrypting the table number of the photovoltaic protocol converter.

[0010] Furthermore, it also includes: a FLASH circuit connected to the power carrier chip.

[0011] The beneficial effects of the technical solution of the present invention are embodied in that: the photovoltaic protocol converter of the present invention uses power line carrier communication technology, has the advantages of no need for wiring, strong reliability, and long communication distance, is suitable for transmission and communication between building groups, can be used on a large scale in photovoltaic power generation scenarios, and for large-scale power generation scenarios of multi-node photovoltaic power systems, the power line carrier communication technology of the photovoltaic protocol converter has greater advantages than wireless; at the same time, the photovoltaic protocol converter can also be compatible with inverter models of most manufacturers, and can achieve the advantages of simple operation, high efficiency, and strong reliability, and has great potential in photovoltaic power generation systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a structural block diagram of a photovoltaic protocol converter based on power line carrier communication technology in an embodiment of the present invention.

[0013] Figure 2 It is a circuit schematic diagram of a power carrier chip in a photovoltaic protocol converter according to an embodiment of the present invention.

[0014] Figure 3 It is a circuit schematic diagram of a power supply filter circuit in a photovoltaic protocol converter according to an embodiment of the present invention.

[0015] Figure 4 It is a circuit schematic diagram of a carrier coupling circuit in a photovoltaic protocol converter according to an embodiment of the present invention.

[0016] Figure 5 1 is a circuit schematic diagram of a zero-crossing circuit in a photovoltaic protocol converter according to an embodiment of the present invention.

[0017] Figure 6 It is a circuit schematic diagram of a power amplifier circuit in a photovoltaic protocol converter according to an embodiment of the present invention.

[0018] Figure 7 It is a circuit schematic diagram of the main control chip circuit in the photovoltaic protocol converter according to an embodiment of the present invention.

[0019] Figure 8 It is a circuit schematic diagram of a 485 circuit in a photovoltaic protocol converter according to an embodiment of the present invention.

[0020] Fig. 9 It is a circuit schematic diagram of the RTC clock circuit in the photovoltaic protocol converter according to an embodiment of the present invention.

[0021] Fig.10 1 is a circuit schematic diagram of a level conversion circuit in a photovoltaic protocol converter according to an embodiment of the present invention.

[0022] Fig.11 It is a circuit schematic diagram of a wireless communication circuit in a photovoltaic protocol converter according to an embodiment of the present invention.

[0023] Fig.12 It is a circuit schematic diagram of an ESAM circuit in a photovoltaic protocol converter according to an embodiment of the present invention.

[0024] Fig.13 It is a circuit schematic diagram of a FLASH circuit in a photovoltaic protocol converter according to an embodiment of the present invention. DETAILED DESCRIPTION

[0025] The present invention will be further described below in conjunction with the accompanying drawings and specific implementation methods and examples. It should be understood that the purpose of providing the examples is only to illustrate, rather than to impose any limitation. For those skilled in the art, several variations and improvements may be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention.

[0026] The purpose of the present invention is to utilize the advantages of power line carrier communication technology in photovoltaic power systems, improve the informatization and visualization of power systems, and develop a new type of power electronic equipment with power line carrier communication technology as the core foundation and wireless communication and 485 communication as auxiliary.

[0027] More specifically, the present invention combines photovoltaic power generation with the inverter system, and uses power line carrier communication technology to collect data and control commands on the photovoltaic power system in real time, thereby greatly improving the stability and real-time monitoring of the system.

[0028] Therefore, the purpose of this invention is to design a photovoltaic protocol converter based on power line carrier communication technology to realize information interaction among photovoltaic users by collecting and real-time monitoring the power generation and power consumption information of photovoltaic users. Figure 1 The photovoltaic protocol converter includes: a power carrier chip 00, a power filter circuit 10, a carrier coupling circuit 20, a zero-crossing circuit 30, a power amplifier circuit 40, a main control chip circuit 50, a 485 circuit 60, a clock circuit 70, a level conversion circuit 80, a wireless communication circuit 90, an ESAM circuit 100 and a FLASH circuit 110. The power carrier chip 00 is simultaneously connected to the carrier coupling circuit 20, the zero-crossing circuit 30, the power amplifier circuit 40, the level conversion circuit 80 and the FLASH circuit 110, and the main control chip circuit 50 is simultaneously connected to the 485 circuit 60, the clock circuit 70, the level conversion circuit 80, the wireless communication circuit 90 and the ESAM circuit 100; the power filter circuit 10 is connected to each of the above circuit modules, and provides working voltage for each circuit module of the photovoltaic protocol converter by filtering the input power and inputting the filtered voltage into each of the above circuit modules.

[0029] Continue to refer Figure 1The power carrier chip 00 modulates and demodulates the carrier signal through the carrier coupling circuit 20, and realizes data transmission and connection with at least one power concentrator through the power line. The power carrier chip 00 transmits the output information to the power concentrator through the carrier coupling circuit 20. In a specific embodiment, the circuit structure of the power carrier chip 00 is as follows Figure 2 As shown, the carrier chip U5 is used to implement the circuit, which mainly includes the carrier chip U5 and its peripheral circuits, and the crystal oscillator XL1. In an exemplary embodiment, the carrier chip U5 can be, for example, a LME3960A1 / QFN80 chip. It should be understood by those skilled in the art that this model is only an example, and other known carrier chips can also be used instead. The peripheral circuits are all known in the art and will not be described in detail here.

[0030] Continue to refer Figure 1 The power filter circuit 10 is used to provide the working voltage for the entire photovoltaic protocol converter. Specifically, the power filter circuit 10 and Figure 1 The other circuit modules shown in the figure are connected, and their function is to filter the input power supply and input the filtered voltage to other circuit modules to provide them with working voltage. In a specific embodiment, the circuit structure of the power filter circuit 10 is as follows: Figure 3 As shown, it mainly includes: DC-DC power supply chip UA1, conduction diodes D7, D8, energy storage inductors LA1, LB1, energy storage capacitor CF1, DC-DC power supply chip U6, energy storage inductor L17, filter inductors L18, L19, feedback resistors R39, R41.

[0031] Continue to refer Figure 1 The carrier coupling circuit 20 is used to transmit the input information received by the power carrier PLC to the power carrier chip 00 through carrier coupling, and transmit the output information of the power carrier sent by the power carrier chip 00 to the slave information processing device through carrier coupling and power line. In a specific embodiment, the circuit structure of the carrier coupling circuit 20 is as follows: Figure 4 As shown, the circuit mainly includes a coupling transformer T1, a semiconductor discharge tube TSS1, a voltage regulator tube TSS2, Schottky diodes D3 and D4, plus peripheral filter resistors and capacitors.

[0032] The main function of the zero-crossing circuit 30 is to transmit information when it is determined that the power line is at a zero-crossing point. In a specific embodiment, the circuit structure of the zero-crossing circuit 30 is as follows: Figure 5 As shown, the circuit structure includes an overcurrent sampling chip U3, an optocoupler diode U4 and their peripheral circuits, wherein R18, R19, R21 and R22 are voltage dividing resistors.

[0033] Continue to refer Figure 1The power amplifier circuit 40 is used to amplify the signal output by the power carrier chip 00, and then load it to the power line through the carrier coupling circuit 20 for transmission to the slave information processing device. In a specific embodiment, the circuit structure of the power amplifier circuit 40 is as follows: Figure 6 As shown, it is mainly implemented by a power amplifier chip U1, and the circuit structure includes the power amplifier chip U1 and its peripheral circuits.

[0034] Continue to refer Figure 1 The main control chip circuit 50 is used to process the information transmitted by the 485 circuit 60, and then transmit the processed information to the external connection device through the 485 circuit 60. It is also used to transmit the information to the power carrier chip 00 through the level conversion circuit 80, and then the carrier coupling circuit 20 transmits the output information to the information processing device. In a specific embodiment, the circuit structure of the main control chip circuit 50 is as follows Figure 7 As shown, it is implemented by a main control chip U7 (such as APM32E103RCT6), and the circuit structure includes the main control chip U7 and its peripheral circuits, and a crystal oscillator Y1.

[0035] Continue to refer Figure 1 , the 485 circuit 60 is connected to the external inverter, and is used to transmit the information of the external inverter to the main control chip circuit 50, and at the same time transmit the control command of the main control chip circuit 50 back to the external inverter for interaction. In a specific embodiment, the circuit structure of the 485 circuit 60 is as follows Figure 8 As shown, U8 is a 485 conversion chip, VP8, VP9, ​​D5, D7 are voltage regulator tubes, plus other resistors and capacitors.

[0036] The clock circuit 70 is used to store device time and transmit information to the information processing device through the main control chip circuit 50. In an exemplary embodiment, the circuit structure of the clock circuit 70 is as follows: Fig. 9 As shown, it is an RTC (real-time) clock, which is implemented using a clock chip U5 (such as RX8025T-UB), and the circuit structure includes the clock chip U5 and its peripheral circuits.

[0037] Continue to refer Figure 1 The level conversion circuit 80 is used to convert the level of the serial port signal between the main control chip circuit 50 and the power carrier chip 00, and plays the role of a level conversion and protection circuit. In an exemplary embodiment, the circuit structure of the level conversion circuit 80 is as follows Fig.10 As shown, Q1 and Q2 are transistors, D9 is a diode, plus other pull-up resistors.

[0038] Continue to refer Figure 1The wireless communication circuit 90 is connected to the main control chip circuit 50 and is used to remotely upgrade the main control chip circuit 50. In an exemplary embodiment, the circuit structure of the wireless communication circuit 90 is as follows: Fig.11 As shown, it is implemented by using a wireless communication chip U10 (such as BLE02D), and the circuit structure includes the wireless communication chip U10 and its peripheral circuits.

[0039] Continue to refer Figure 1 , ESAM (Embedded Secure Access Module, embedded security control chip) circuit 100 is connected to the main control chip circuit 50, and is used to encrypt the table number of the photovoltaic protocol converter. In an exemplary embodiment, the circuit structure of the ESAM circuit 100 is as follows Fig.12 As shown, it is implemented by using ESAM chip U9, and the circuit structure includes ESAM chip U9 and its peripheral circuits.

[0040] Continue to refer Figure 1 , the FLASH circuit 110 is connected to the power carrier chip 00, and an exemplary circuit structure thereof is as follows Fig.13 As shown, a storage chip U4 (such as BY25Q32CSTIG) can be used to implement it.

[0041] The above contents are further detailed descriptions of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art of the present invention, several equivalent substitutions or obvious variations can be made without departing from the concept of the present invention, and the performance or use is the same, which should be regarded as belonging to the protection scope of the present invention.

Claims

1. A photovoltaic protocol converter based on power line carrier communication technology, characterized in that: include: Power carrier chip, power filter circuit, carrier coupling circuit, zero-crossing circuit, power amplifier circuit, main control chip circuit, 485 circuit, clock circuit and level conversion circuit; The power carrier chip modulates and demodulates the carrier signal through the carrier coupling circuit, realizes data transmission through the power line and connects to at least one of the power concentrators; The power supply filter circuit provides a working voltage for the photovoltaic protocol converter by filtering the input power supply; The carrier coupling circuit is used to transmit the input information received by the power carrier to the power carrier chip through carrier coupling, and transmit the output information of the power carrier sent by the power carrier chip to the slave information processing device through carrier coupling and power line; The zero-crossing circuit transmits information by judging when the power line crosses the zero point; The power amplifier circuit is used to amplify the signal output by the power carrier chip, and then load it onto the power line through the carrier coupling circuit and transmit it to the slave information processing device; The main control chip circuit is used to process the information transmitted by the 485 circuit, and then transmit the processed information to the external connection device through the 485 circuit. It is also used to transmit the information to the power carrier chip through the level conversion circuit, and then the carrier coupling circuit transmits the output information to the information processing device; The 485 circuit is used to transmit the information of the external inverter to the main control chip circuit, and at the same time transmit the control command of the main control chip circuit back to the external inverter for interaction; The clock circuit is used to store device time and transmit information to the information processing device through the main control chip circuit; The level conversion circuit is used to perform level conversion on the serial port signal between the main control chip circuit and the power carrier chip, and plays the role of a level conversion and protection circuit.

2. The photovoltaic protocol converter according to claim 1, characterized in that: The power carrier chip transmits the output information to the power grid concentrator through the carrier coupling circuit.

3. The photovoltaic protocol converter according to claim 1, characterized in that: Also includes: The wireless communication circuit is connected to the main control chip circuit and is used for remotely upgrading the main control chip circuit.

4. The photovoltaic protocol converter according to claim 3, characterized in that: Also includes: The ESAM circuit is connected to the main control chip circuit and is used to encrypt the table number of the photovoltaic protocol converter.

5. The photovoltaic protocol converter according to claim 4, characterized in that: Also includes: The FLASH circuit is connected to the power carrier chip.

Images