SOLAR MODULE, SOLAR MODULE-INTEGRABLE ASSEMBLY AND POWER GENERATION SYSTEM

Abstract

The disclosure relates to a solar module, which includes a plurality of solar cells which are interconnected to generate a direct-voltage power at module terminals, and a receiving unit for receiving an accurate time signal. The solar module further includes a communication unit for the synchronous transmission of the received accurate time signal to an inverter. The inverter is connected to the solar module by means of direct-voltage lines. The disclosure also relates to an assembly that can be integrated into a solar module, and to an energy generation system having a solar module of this type.

Claims

1. A solar module comprising: a plurality of solar cells connected together to generate a DC power applied to module terminals, a receiving unit configured to receive a precision time signal, and a communication unit configured to time-synchronously transmit the received precision time signal to an inverter connected to the module terminals of the solar module via DC lines.

2. The solar module according to claim 1, wherein the receiving unit and the communication unit are configured to be supplied power from the DC power generated by one or more of the plurality of solar cells.

3. The solar module according to claim 1, wherein the communication unit comprises a PLC unit configured to transmit the precision time signal to the inverter via the DC lines.

4. The solar module according to claim 1, wherein the communication unit comprises a radio unit configured to transmit the received precision time signal to the inverter via a wireless transmission.

5. The solar module according to claim 1 in combination with an inverter to form a power generation system, the inverter comprising a device configured to detect a point in time with a fixed phase reference within a voltage profile of a connected network, wherein the point in time is related to the precision time signal.

6. The solar module according to claim 5, wherein the inverter is further configured to store and transmit the detected point in time.

7. The solar module according to claim 5, wherein the device is configured to detect a voltage zero crossing as the point in time with a fixed phase reference.

8. A solar module-integrable arrangement, comprising: a receiving unit configured to receive a precision time signal; and a communication unit configured to transmit the received precision time signal to an inverter connected to the solar module via DC lines.

9. The solar module-integrable arrangement according to claim 8, wherein the receiving unit and the communication unit are configured to be supplied power from the DC power generated by one or more of the plurality of solar cells.

10. The solar module-integrable arrangement according to claim 8, wherein the communication unit comprises a PLC unit configured to transmit the precision time signal to the inverter via the DC lines.

11. The solar module-integrable arrangement according to claim 8, wherein the communication unit comprises a radio unit configured to transmit the received precision time signal to the inverter via a wireless transmission.

12. A power generation system comprising: a solar module comprising: a plurality of solar cells connected together to generate a DC power applied to module terminals, a receiving unit configured to receive a precision time signal, and a communication unit, an inverter connected to the module terminals of the solar module via DC lines, wherein the communication unit is configured to time-synchronously transmit the received precision time signal to the inverter, and wherein the inverter is configured to detect a point in time with a fixed phase reference within a voltage profile of a connected grid, wherein the point in time is related to the precision time signal.

13. The power generation system according to claim 12, wherein the inverter is further configured to store and transmit the detected point in time.

14. The power generation system according to claim 12, wherein the inverter is configured to detect a voltage zero crossing of the connected grid as the point in time with a fixed phase reference.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In the following, the disclosure is illustrated with the aid of figures, of which

[0016] FIG. 1 shows an embodiment of a solar module according to the disclosure and of a solar module-integrable arrangement; and

[0017] FIG. 2 shows a power generation system according to the disclosure.

DETAILED DESCRIPTION

[0018] FIG. 1 shows a solar module 1 in which a plurality of solar cells 8 are connected in series to generate DC power. The DC voltage power is led out of the solar module 1 via DC voltage lines 6 in order to connect it to other solar modules or to an inverter. In this case, the DC voltage lines 6 are routed through an arrangement 2, in particular an arrangement integrated in a junction box of the solar module. Within the arrangement 2, a communication unit 4 and a receiving unit 3 for electrical supply are connected to the DC lines 6. Furthermore, an antenna 5 is connected to the receiving unit 3, via which the receiving unit 3 can receive a precision time signal, for example a satellite-based GPS signal, via which a high-precision reference time can be obtained. The reference timing information is transmitted to the communication unit 4 connected to the receiving unit 3. The communication unit 4 is arranged to convert the reference time into a data signal of suitable format and to transmit it to an inverter. In this case, the data signal contains the reference time, and the format as well as the signal frequency are selected such that the receiver can determine a reception time with a sufficient accuracy, for example, an accuracy of less than 10 μs, for example, less than 1 μs. Corresponding formats or usable frequency ranges are known to the skilled person.

[0019] Transmission by the communication unit 4 may be by radio, or it may be by modulating the data signal onto the DC power lines 6, for example, inductively or capacitively as a high frequency signal. By demodulation, the data signal can then be obtained and evaluated by the inverter from the DC voltage lines. In the case of transmission by radio, inverters which are not connected to the solar module 1 via the DC voltage lines 6 can also be supplied with the information about the reference time.

[0020] It should be noted at this point that time delays occur over the entire transmission path of the precision time signal, which are caused, among other things, by the length of the transmission path, the generation or the evaluation of the signals. However, absolute synchronism with a reference clock is not required for the usability of the reference timing, only relative synchronism. Therefore, constant time delays are not relevant here.

[0021] In FIG. 2, a power generation system in the form of a building is shown with a PV system installed on a building roof comprising solar modules 10. The solar modules 10 are connected to each other, to an arrangement 2 and to an inverter 11 via DC power lines 6. The arrangement 2 is shown here as a stand-alone arrangement, but may be integrated into one of the solar modules 10, as shown in connection with the description of FIG. 1. The inverter 11 converts a DC power from the solar modules 10, supplied via the DC lines 6, into an AC power, which it outputs to a connected grid 12, but also to loads 13 within the building, if applicable.

[0022] The arrangement 2 is arranged to receive a precision time signal from a time signal generator 14, in this case a satellite, and is located with the roof at a location where the precision time signal from the time signal generator 14 can be received. The received timing signal is alternatively transmitted by the arrangement 2 as a radio signal or as a PLC signal modulated onto the DC power to the inverter 11, which is configured to receive the transmitted signal. The inverter 11 is not able to directly receive the precision time signal from the time signal generator 14 due to its installation location, for example in a basement of the building.

[0023] Furthermore, the inverter is configured to detect a point in time with a fixed phase reference within a voltage curve of the connected grid 12, for example, a voltage zero crossing, to relate this point in time to the received time signal and to store it. For this purpose, the inverter may comprise a PLL (phase locked loop) circuit. Instead of a single point in time with a fixed phase reference, a grid frequency or a grid frequency curve with a start or end point in time related to the received time signal can also be determined and stored, so that a notification of a plurality of detected points in time is provided, which increases the accuracy of the detection.

[0024] The data stored in this way about times and/or network frequencies or network frequency characteristics can be transmitted to a central evaluation unit for such data at a later time.

[0025] Since inverters in any case have a PLL circuit or other suitable circuit for determining a point in time with a fixed phase reference within a voltage waveform of the connected grid 12 for their operation, and regularly also have components for receiving the time signal for other communication purposes, a power generation system according to the disclosure can do without additional components on the inverter side.

[0026] The arrangement 2 can also be retrofitted into an existing power generation system. For this purpose, it can be installed in a junction box of an existing solar module and connected to the DC lines. However, it is also conceivable to provide an additional connection unit, for example, a connection unit that is simply clipped over the DC lines by means of an insulation displacement technique, such as described in the publication DE 20 2012 103 480 U1.