CN203365538U - Photovoltaic power generation monitoring device - Google Patents

Abstract

The utility model provides a photovoltaic power generation monitoring device, comprising: an acquisition unit, a communication unit and a monitoring unit, the input end of the acquisition unit is connected to the output end of the photovoltaic panel, the output end of the acquisition unit is connected to the communication unit, the acquisition unit Collect the current value, voltage value and temperature value in the photovoltaic panel, and send the current signal, voltage signal and temperature signal obtained according to the current value, voltage value and temperature value to the communication unit; the communication unit is connected to the acquisition unit and The monitoring unit sends the received current signal, voltage signal and temperature signal to the monitoring unit; the monitoring unit is connected to the communication unit, and outputs the working status signal of the photovoltaic panel according to the current signal, voltage signal and temperature signal. Through this technical solution, the collection and remote transmission of the voltage, current and temperature of the photovoltaic panel can be realized, thereby realizing the detection of a single photovoltaic module.

Description

Photovoltaic power generation monitoring device

technical field

The utility model relates to the technical field of photovoltaic power generation, in particular to a photovoltaic power generation monitoring device.

Background technique

It is predicted that solar photovoltaic power generation will occupy an important seat in the world's energy consumption in the 21st century, not only to replace some conventional energy sources, but also to become the main body of the world's energy supply. It is estimated that by 2030, renewable energy will account for more than 30% of the total energy structure, and solar photovoltaic power generation will account for more than 10% of the world's total power supply; by 2040, renewable energy will account for the total More than 50% of energy consumption, solar photovoltaic power generation will account for more than 20% of total electricity; by the end of the 21st century, renewable energy will account for more than 80% of the energy structure, and solar power will account for more than 60%. These figures are enough to show the development prospects of the solar photovoltaic industry and its important strategic position in the energy field.

The core component of photovoltaic modules is the solar cell. Generally speaking, the electrical characteristics of the solar cells used in each module should be basically the same, otherwise the so-called hot spot effect will occur on the cells with poor electrical performance or blocked (problem cells). If the current between the battery strings is inconsistent, you can see the so-called step curve or abnormal curve on the characteristic curve of the component connected with the bypass diode. If the performance of the solar cells in the module is inherently inconsistent, it will inevitably lead to hot spots in the module. We can see the existence of module hot spots through the output characteristic curve of the module and infrared imaging. If the efficiency of the solar cells in the components decreases after light attenuation, the performance of the solar cells in the components is inconsistent. We can test the output characteristic curves of the components before and after attenuation and infrared imaging to see the changes of the components before and after illumination.

In the production process of photovoltaic modules, due to the defects of the silicon material itself and the reasons of battery manufacturing (such as: incomplete edge removal, edge short circuit, excessive edge removal, P-type layer extends to the center of the N-type layer, edge grid lines cause local short circuit, poor sintering , Poor contact between the positive electrode or the back electrode and the silicon chip, the increase of series resistance, excessive sintering, and the PN junction will be burnt through and short-circuited) resulting in deviations in characteristics. Therefore, it is very important for photovoltaic power generation systems to monitor the operation of photovoltaic modules and find problematic components in time.

At present, the photovoltaic power generation monitoring system is mainly based on the monitoring of the combiner box and the inverter system, such as: "Acrel-2000V8.0 photovoltaic power station power monitoring system" launched by Acrel Company, " Real-time monitoring and information collection system for distributed photovoltaic power generation". The above system can only monitor the working status of a string of components, and cannot detect the problems that occurred in the early stage of a single component, and there is a monitoring dead zone.

Therefore, a new technical solution is needed, which can realize the monitoring of a single photovoltaic module.

Utility model content

Based on the above problems, the utility model proposes a new technical solution, which can realize the monitoring of a single photovoltaic module.

In view of this, the utility model proposes a photovoltaic power generation monitoring device, which is applied to a photovoltaic power generation system, including: an acquisition unit, a communication unit and a monitoring unit, wherein the input end of the acquisition unit is connected to the output end of the photovoltaic panel, The output end of the acquisition unit is connected to the communication unit, and the acquisition unit acquires the current signal value, voltage signal value and temperature signal value in the photovoltaic panel, and according to the current signal value, the voltage signal value The current value flow signal, voltage value signal and temperature value signal obtained by the value and the temperature signal value are sent to the communication unit; the communication unit is connected to the acquisition unit and the monitoring unit, and the received The current signal, the voltage signal and the temperature signal are sent to the monitoring unit; the monitoring unit is connected to the communication unit, and according to the current signal, the voltage signal and the temperature signal, the output Describe the working status signal of the photovoltaic panel.

In this technical solution, real-time online monitoring of the operation of the photovoltaic modules, and upload the working voltage, current and temperature of the photovoltaic panels to the monitoring unit. Maintenance personnel deal with it in time to prevent faulty components from being found in time during the operation of photovoltaic modules, which will seriously affect the power generation efficiency of the entire group of components and even cause fire accidents.

In the above technical solution, preferably, further comprising: a power supply unit connected to the acquisition unit, the communication unit and the monitoring unit, providing working power for the acquisition unit, the communication unit and the monitoring unit .

In this technical solution, the power supply unit includes a step-down conversion circuit. Among them, the output of the photovoltaic panel can be directly used as the input of the power module, so its input adopts a wide range input, and it can work normally within the input range of 9V to 50V. The power module adopts a step-down conversion circuit (ie, BUCK circuit), which converts and stabilizes the input voltage to 5V, and provides working power for the acquisition and communication circuits.

In the above technical solution, preferably, the collection unit includes: a current collection subunit connected to the output terminal of the photovoltaic panel to collect and output the current value of the photovoltaic panel; a voltage collection subunit connected to the The output terminal of the photovoltaic panel collects and outputs the voltage value of the photovoltaic panel; the temperature acquisition subunit is connected to the output terminal of the photovoltaic panel and collects and outputs the temperature value of the photovoltaic panel.

In this technical solution, the current acquisition can use constantan wire to convert the current into a voltage signal, and then the amplifying circuit is amplified and transformed, and then sent to the A/D acquisition circuit of the single-chip microcomputer, and then the current is calculated through the analog-to-digital conversion and signal processing program the size of. The voltage collection can be collected by voltage division, and the temperature collection can be collected by platinum resistance. Of course, the acquisition methods are not limited to the above-mentioned ones, and data acquisition can also be performed by collecting voltage sensors, temperature sensors, and current sensors.

In the above technical solution, preferably, the acquisition unit further includes: a signal amplification unit, an analog/digital converter, and a sending unit, wherein the signal amplification unit is connected to the current acquisition subunit, the voltage acquisition The subunit and the temperature acquisition subunit differentially amplify the received current value, the voltage value and the temperature value and send them to the analog/digital converter; the analog/digital converter, Connecting to the signal amplifying unit, performing analog-to-digital conversion on the differentially amplified current value, voltage value and temperature value received from the signal amplifying unit to obtain the current signal, the voltage signal and the temperature signal; The sending unit is connected to the analog/digital converter, and sends the current signal, the voltage signal and the temperature signal to the communication unit.

In the above technical solution, preferably, the signal amplifying unit includes a protection circuit, a filter circuit and an amplifying circuit, wherein the output terminals of the current acquisition subunit, the voltage acquisition subunit and the temperature acquisition subunit are connected to To the input end of the protection circuit, the output end of the protection circuit is connected to the input end of the filter circuit, the output end of the filter circuit is connected to the input end of the amplification circuit, and the output end of the amplification circuit connected to the A/D converter.

In the above technical solution, preferably, the protection circuit includes at least one diode, the filter circuit includes a filter capacitor and a filter resistor, one end of the filter capacitor is connected to one end of the filter resistor, and the other end of the filter resistor One end is connected to the cathode of the at least one diode, and the other end of the filtering capacitor is connected to the anode of the at least one diode.

In the above technical solution, preferably, the amplifying circuit includes an operational amplifier, an input terminal resistor and at least one feedback resistor, and the input terminal resistor is connected between the output terminal of the filter circuit and the inverting input terminal of the operational amplifier Between, the at least one feedback resistor is connected between the inverting input terminal of the operational amplifier and the output terminal of the operational amplifier.

In the above technical solution, preferably, the communication unit includes a CC2530 chip.

In this technical solution, the communication unit can use both wired communication and wireless communication. For wireless communication, CC2530 control chip can be used. This chip has the characteristics of low power consumption and long transmission distance. Its main technical parameters are: transmission power 10mW-1W; carrier frequency 433MHz, 470MHz, also can provide 86 to 915MHz carrier frequency, ISM frequency band, no need to apply for frequency point; based on GFSK modulation method, adopts efficient forward error correction channel coding technology, which improves data burst resistance The ability of interference and random interference, when the channel bit error rate is 10 ^-4 , the actual bit error rate can be obtained from 10 ^-7 to 10 ^-8 ; in the case of line of sight, the antenna height is > 2 meters, and the reliable transmission distance can reach 800 -5000m(BER=1200bps); provide transparent data interface, which can adapt to any standard or non-standard user protocol; standard configuration provides 8 channels, which can be expanded to 116 channels if required by users; 2 serial ports and 3 interface modes , COM1 is a TTL level UART interface; the interface baud rate is 1200/2400/4800/9600/19200/38400bps, the format is 8N1/8E1 user-defined, can transmit unlimited data frames, and user programming is more flexible; +5V In the case of power supply, the receiving current is <30mA, the transmitting current is <40mA, and the sleep current is <5uA. In the case of +2.7V power supply, the receiving current is <22mA, the transmitting current is <33mA, and the sleep current is <5uA; a variety of antenna configuration schemes can meet different needs of users application needs.

In the above technical solution, preferably, the monitoring unit includes a display.

In the above technical solution, preferably, further comprising: a display unit connected to the collection unit to display the current value, the voltage value and the temperature value.

In the above technical solution, preferably, the display unit includes: a display screen and/or an indicator light.

Through the above technical solutions, the collection and remote transmission of the voltage, current and temperature of the photovoltaic panel can be realized, thereby realizing the detection of a single photovoltaic module.

Here, those skilled in the art should understand that the above-mentioned unit modules can be realized by using various existing products, including but not limited to the following examples:

Acquisition unit can choose high-precision integrated sensor;

The monitoring unit can choose the display screen of model MSG12864;

The current acquisition sub-unit can choose the current sensor of the background scale Fangyuan Sensor Co., Ltd.;

The voltage acquisition sub-unit can choose the voltage sensor of the background scale Fangyuan Sensor Co., Ltd.;

The temperature acquisition sub-unit can choose the temperature sensor from the background scale Fangyuan Sensor Co., Ltd.;

The controller can use the model FX06 controller of Beijing Nengde Wisdom Technology Co., Ltd.;

The A/D converter can use the serial chip ADS7816.

Description of drawings

Fig. 1 shows a block diagram of a photovoltaic power generation monitoring device according to an embodiment of the present invention;

Fig. 2 shows the schematic diagram of the acquisition unit according to an embodiment of the present utility model;

Figure 3 shows a schematic diagram of a power supply unit according to an embodiment of the present invention;

Fig. 4 shows the schematic diagram of the signal amplifying unit according to the embodiment of the present utility model;

Fig. 5 shows a schematic diagram of a communication unit according to an embodiment of the present invention.

Detailed ways

In order to more clearly understand the above purpose, features and advantages of the utility model, the utility model will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that, in the case of no conflict, the embodiments of the present application and the features in the embodiments can be combined with each other.

In the following description, a lot of specific details have been set forth in order to fully understand the utility model, but the utility model can also be implemented in other ways different from those described here, therefore, the protection scope of the utility model is not limited by the following limitations of the specific embodiments disclosed.

Fig. 1 shows a block diagram of a photovoltaic power generation monitoring device according to an embodiment of the present invention.

As shown in Fig. 1, a photovoltaic power generation monitoring device 100 according to an embodiment of the present invention includes: an acquisition unit 104, a communication unit 106, and a monitoring unit 108, wherein the input end of the acquisition unit 104 is connected to the output of the photovoltaic panel terminal, the output terminal of the collection unit 104 is connected to the communication unit 106, the collection unit 104 collects the current signal value, voltage signal value and temperature signal value in the photovoltaic panel, and will , the current value flow signal, the voltage value signal and the temperature value signal obtained by the voltage signal value and the temperature signal value are sent to the communication unit 106; the communication unit 106 is connected to the acquisition unit 104 and the The monitoring unit 108 sends the received current signal, the voltage signal and the temperature signal to the monitoring unit 108; the monitoring unit 108 is connected to the communication unit 106, and according to the current signal, The voltage signal and the temperature signal output the working state signal of the photovoltaic panel.

In this technical solution, real-time online monitoring of the operation of the photovoltaic modules, and upload the working voltage, current and temperature of the photovoltaic panels to the monitoring unit. Maintenance personnel deal with it in time to prevent faulty components from being found in time during the operation of photovoltaic modules, which will seriously affect the power generation efficiency of the entire group of components and even cause fire accidents.

In the above technical solution, preferably, further comprising: a power supply unit 102, connected to the collection unit 104, the communication unit 106 and the monitoring unit 108, providing power for the collection unit 104, the communication unit 106 and the monitoring unit 108 The monitoring unit 108 provides working power.

In this technical solution, the power supply unit includes a step-down conversion circuit. Among them, the output of the photovoltaic panel can be directly used as the input of the power module, so its input adopts a wide range input, and it can work normally within the input range of 9V to 50V. The power module adopts a step-down conversion circuit (ie, BUCK circuit), which converts and stabilizes the input voltage to 5V, and provides working power for the acquisition and communication circuits.

In the above technical solution, preferably, further comprising: a display unit 110, connected to the acquisition unit, for displaying the current value, the voltage value and the temperature value.

In the above technical solution, preferably, the display unit 110 includes: a display screen and/or an indicator light.

Fig. 2 shows a schematic diagram of an acquisition unit according to an embodiment of the present invention.

As shown in Figure 2, the collection unit 104 according to the embodiment of the present utility model includes: a current collection subunit 1042, connected to the output terminal of the photovoltaic panel, collecting and outputting the current value of the photovoltaic panel; a voltage collection subunit 1044, connected to the output terminal of the photovoltaic panel, collecting and outputting the voltage value of the photovoltaic panel; the temperature collection subunit 1046, connected to the output terminal of the photovoltaic panel, collecting and outputting the temperature value of the photovoltaic panel.

In this technical solution, the current acquisition can use constantan wire to convert the current into a voltage signal, and then the amplifying circuit is amplified and transformed, and then sent to the A/D acquisition circuit of the single-chip microcomputer, and then the current is calculated through the analog-to-digital conversion and signal processing program the size of. The voltage collection can be collected by voltage division, and the temperature collection can be collected by platinum resistance. Of course, the acquisition methods are not limited to the above-mentioned ones, and data acquisition can also be performed by collecting voltage sensors, temperature sensors, and current sensors.

In the above technical solution, preferably, the acquisition unit 104 further includes: a signal amplification unit 1048, an analog/digital converter 10410, and a sending unit 10412, wherein the signal amplification unit 1048 is connected to the current acquisition subunit 1042. The voltage acquisition subunit 1044 and the temperature acquisition subunit 1046 differentially amplify the received current value, voltage value and temperature value and send them to the analog/digital converter 10410 The A/D converter 10410 is connected to the signal amplifying unit 1048, and performs analog-to-digital conversion on the differentially amplified current value, voltage value and temperature value received from the signal amplifying unit to obtain the current signal , the voltage signal and the temperature signal; the sending unit 10412 is connected to the analog/digital converter 10410, and sends the current signal, the voltage signal and the temperature signal to the communication unit 106 .

In the above technical solution, preferably, the signal amplifying unit 1048 includes a protection circuit, a filter circuit and an amplifying circuit, wherein the output terminals of the current acquisition subunit, the voltage acquisition subunit and the temperature acquisition subunit Connected to the input end of the protection circuit, the output end of the protection circuit is connected to the input end of the filter circuit, the output end of the filter circuit is connected to the input end of the amplification circuit, the output of the amplification circuit connected to the A/D converter.

In the above technical solution, preferably, the protection circuit includes at least one diode, the filter circuit includes a filter capacitor and a filter resistor, one end of the filter capacitor is connected to one end of the filter resistor, and the other end of the filter resistor One end is connected to the cathode of the at least one diode, and the other end of the filtering capacitor is connected to the anode of the at least one diode.

In the above technical solution, preferably, the amplifying circuit includes an operational amplifier, an input terminal resistor and at least one feedback resistor, and the input terminal resistor is connected between the output terminal of the filter circuit and the inverting input terminal of the operational amplifier Between, the at least one feedback resistor is connected between the inverting input terminal of the operational amplifier and the output terminal of the operational amplifier.

Fig. 3 shows a schematic diagram of a power supply unit according to an embodiment of the present invention.

As shown in FIG. 3 , the power supply unit according to the embodiment of the present invention includes a step-down conversion circuit. In this technical solution, the output of the photovoltaic panel can be directly used as the input of the power module, so its input adopts a wide range input, and it can work normally within the input range of 9V-50V. The power module adopts a step-down conversion circuit (ie, BUCK circuit), which converts and stabilizes the input voltage to 5V, and provides working power for the acquisition and communication circuits.

Fig. 4 shows a schematic diagram of a signal amplifying unit according to an embodiment of the present invention.

As shown in Figure 4, the signal amplifying unit according to the embodiment of the present invention includes an operational amplifier (such as LM324 operational amplifier) and at least one feedback resistor (such as R4, R5). After the at least one feedback resistor is connected in series, it is connected to the operational Between the inverting input terminal and the output terminal of the amplifier, the current signal, the voltage signal and the temperature signal are differentially amplified by the operational amplifier and the at least one feedback resistor. In addition to the differential amplifier circuit, the conversion circuit is also shown in Figure 4. For example, when collecting the current signal, the current signal is converted into a voltage signal through the resistor (R1), and then amplified and transformed by the differential amplifier circuit, and then sent to the microcontroller The A/D collects the circuit, and then calculates the size of the current through the analog-to-digital conversion and signal processing program.

Fig. 5 shows a schematic diagram of a communication unit according to an embodiment of the present invention.

The communication unit can use both wired communication and wireless communication. In a preferred example, as shown in Figure 5, the CC2530 control chip can be used to realize wireless communication. This chip has the characteristics of low power consumption and long transmission distance. The main technical parameters are: transmit power 10mW-1W; carrier frequency 433MHz, 470MHz, 86-915MHz carrier frequency, ISM frequency band, no need to apply for frequency points; GFSK-based modulation method, using efficient forward error correction channel coding technology , which improves the ability of data to resist burst interference and random interference. When the channel bit error rate is 10 ^-4 , the actual bit error rate can be obtained from 10 ^-7 to 10 ^-8 ; in the case of line-of-sight, the antenna height is > 2 meters , the reliable transmission distance can reach 800-5000m (BER=1200bps); provide a transparent data interface, which can adapt to any standard or non-standard user protocol; standard configuration provides 8 channels, which can be expanded to 116 channels if required by users; 2 serial ports and 3 interface modes, COM1 is a TTL level UART interface; the interface baud rate is 1200/2400/4800/9600/19200/38400bps, the format is 8N1/8E1 user-defined, and can transmit unlimited data frames. User programming is more flexible; in the case of +5V power supply, the receiving current is <30mA, the transmitting current is <40mA, and the sleep current is <5uA; in the case of +2.7V power supply, the receiving current is <22mA, the transmitting current is <33mA, and the sleep current is <5uA; Antenna configuration schemes to meet different application needs of users.

The technical solution of the utility model has been described in detail above in conjunction with the accompanying drawings. Through the technical solution of the utility model, the collection and remote transmission of the voltage, current and temperature of the photovoltaic panel can be realized, thereby realizing the detection of a single photovoltaic module.

The above descriptions are only preferred embodiments of the utility model, and are not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present utility model shall be included in the protection scope of the present utility model.

Claims (10)

1. A photovoltaic power generation monitoring device, which is applied to a photovoltaic power generation system, is characterized in that it includes: an acquisition unit, a communication unit and a monitoring unit, wherein, The input terminal of the collection unit is connected to the output terminal of the photovoltaic panel, the output terminal of the collection unit is connected to the communication unit, the collection unit collects the current value, voltage value and temperature value in the photovoltaic panel, and Send the current signal, voltage signal and temperature signal obtained according to the current value, the voltage value and the temperature value to the communication unit; The communication unit is connected to the acquisition unit and the monitoring unit, and sends the received current signal, voltage signal and temperature signal to the monitoring unit; The monitoring unit is connected to the communication unit, and outputs a working state signal of the photovoltaic panel according to the current signal, the voltage signal and the temperature signal. the 2. The photovoltaic power generation monitoring device according to claim 1, further comprising: The power supply unit is connected to the acquisition unit, the communication unit and the monitoring unit, and provides working power for the acquisition unit, the communication unit and the monitoring unit. the 3. The photovoltaic power generation monitoring device according to claim 1, wherein the acquisition unit comprises: The current acquisition subunit is connected to the output terminal of the photovoltaic panel, and collects and outputs the current value of the photovoltaic panel; The voltage acquisition subunit is connected to the output terminal of the photovoltaic panel, and collects and outputs the voltage value of the photovoltaic panel; The temperature acquisition subunit is connected to the output terminal of the photovoltaic panel, and collects and outputs the temperature value of the photovoltaic panel. the 4. The photovoltaic power generation monitoring device according to claim 3, wherein the acquisition unit further comprises: a signal amplification unit, an analog/digital converter and a sending unit, wherein, The signal amplifying unit is connected to the current acquisition subunit, the voltage acquisition subunit and the temperature acquisition subunit, and differentially amplifies the received current value, the voltage value and the temperature value sent to the analog/digital converter; The A/D converter is connected to the signal amplifying unit, and performs analog-to-digital conversion on the differentially amplified current value, voltage value and temperature value received from the signal amplifying unit to obtain the current signal, the voltage signal and said temperature signal; The sending unit is connected to the analog/digital converter, and sends the current signal, the voltage signal and the temperature signal to the communication unit. the 5. The photovoltaic power generation monitoring device according to claim 4, wherein the signal amplifying unit includes a protection circuit, a filter circuit and an amplifying circuit, wherein, The output terminals of the current collection subunit, the voltage collection subunit and the temperature collection subunit are connected to the input terminal of the protection circuit, the output terminal of the protection circuit is connected to the input terminal of the filter circuit, The output terminal of the filtering circuit is connected to the input terminal of the amplifying circuit, and the output terminal of the amplifying circuit is connected to the analog/digital converter. the 6. The photovoltaic power generation monitoring device according to claim 5, wherein the protection circuit includes at least one diode, the filter circuit includes a filter capacitor and a filter resistor, and one end of the filter capacitor is connected to the filter resistor One end of the filter resistor, the other end of the filter resistor is connected to the cathode of the at least one diode, and the other end of the filter capacitor is connected to the anode of the at least one diode. the 7. The photovoltaic power generation monitoring device according to claim 5, wherein the amplifying circuit comprises an operational amplifier, an input terminal resistor and at least one feedback resistor, and the input terminal resistor is connected to the output terminal of the filter circuit and Between the inverting input terminals of the operational amplifier, the at least one feedback resistor is connected between the inverting input terminal of the operational amplifier and the output terminal of the operational amplifier. the 8. The photovoltaic power generation monitoring device according to claim 2, wherein the power supply unit comprises a step-down conversion circuit. the 9. The photovoltaic power generation monitoring device according to any one of claims 1 to 8, further comprising: a display unit, which is connected to the acquisition unit, and the current value, the voltage value and the temperature value are displayed. the 10. The photovoltaic power generation monitoring device according to claim 9, wherein the display unit comprises: a display screen and/or an indicator light. the

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