CN102916056A - Solar battery pack protection circuit, solar junction box and solar power generation system - Google Patents

Abstract

The invention relates to the technical field of solar power generation, in particular to a solar battery pack protection circuit, a solar junction box and a solar power generation system. The technical scheme is that the solar battery pack protection circuit comprises a bypass diode, an electronic switch and a thermoelectric generator, wherein the bypass diode is in reversed-polarity parallel connection with a solar battery piece group consisting of battery pieces that are connected in series, the electronic switch is connected with the bypass diode in parallel, and the thermoelectric generator is in thermal coupling with the bypass diode, can realize the breakover of the electronic switch under a set temperature and can realize the turn-off of the electronic switch under another set temperature. According to the solar battery pack protection circuit, the solar junction box and the solar power generation system, the temperature rise of the bypass diode can be effectively limited, and the power consumption of the protection circuit can be reduced.

Description

Solar module protective circuit, solar junction box and solar power system

Technical field

The present invention relates to solar energy generation technology, particularly solar module protective circuit, solar junction box and solar power system.

Background technology

Existing invention has proposed a kind of unidirectional bypass protection circuit for the problems of excessive heat of the bypass diode in the battery component that is connected in series by cell piece, such as United States Patent (USP) 7898114, the disclosed bypass protection principle of this patent can be referring to Fig. 1, a string cell piece that is connected in series, bridge joint the bypass diode BD of the pole reversal, bypass diode BD parallel connection electronic switching device T1 and control the control circuit of described electronic switch; Therefore, one or more cell pieces are blocked in the cell piece string, hinder electric current and flow through all the other normal cell pieces in the cell piece string, at this moment, forward biased bypass diode BD provides a forward voltage drop VF, for the about 0.6V of this forward voltage drop of silicon device, be enough to make low threshold switch T2 conducting, and by charge pump circuit capacitor C charged; And the electric charge on the capacitor C is used to unlocking electronic switch T1 and enters conducting state, and the power consumption on unlocking electronic switch T1 and the bypass diode BD is distributed, thereby the low on-resistance of electronic switch T1 reduces to reduce power consumption so that flow through the electric current of bypass diode BD; When capacitor C discharge off, electronic switch T1 reenters off state, and above-mentioned charging process is restarted; This periodic power consumption between bypass diode BD and electronic switch T1 is distributed, and is conducive to slow down the programming rate of bypass diode BD; Yet the forward voltage drop VF of bypass diode can reduce along with the temperature rise of bypass diode, can be decreased to 0.3V from 0.6V; even lower; thereby cause the cycle of electronic switch T1 conducting and shutoff elongated, be unfavorable for reducing the temperature rise of bypass diode, so that the protective circuit power consumption is higher.

Summary of the invention

One of purpose of the present invention provides a kind of solar module protective circuit, and it can effectively limit the temperature rise of bypass diode, reduces the power consumption of protective circuit.

Above-mentioned technical purpose of the present invention is achieved by the following technical programs: a kind of solar module protective circuit; the solar battery sheet group reversed polarity bypass diode in parallel that comprises and be comprised of the cell piece that is connected in series also comprises the electronic switch that is parallel to described bypass diode, is thermally coupled in bypass diode and can and turn-offs the thermoelectric generator of described electronic switch at another design temperature at the described electronic switch of design temperature conducting.

When having cell piece to be blocked, the bypass diode conducting, along with uprising of bypass diode temperature rise, when reaching design temperature, because thermoelectric generator is thermally coupled in bypass diode, so that thermoelectric generator produces enough electromotive forces, thereby drive the electronic switch conducting, and then the distribution of the power consumption between unlocking electronic switch and the bypass diode, thereby the power consumption of reduction bypass diode reduces the temperature rise of bypass diode, when the temperature rise of bypass diode is reduced to another design temperature, because thermoelectric generator is thermally coupled in bypass diode, the electromotive force that thermoelectric generator produces has been not enough to the conducting electronic switch, thereby so that the electronic switch shutoff; Yet when the temperature rise of bypass diode reached the design temperature that can make thermoelectric generator produce the electromotive force that makes the electronic switch conducting again, electronic switch is conducting again; And then the power consumption between periodic unlocking electronic switch and the bypass diode is distributed, thereby effectively limits the temperature rise of bypass diode, reduces the power consumption of bypass circuit, improves the reliability of protective circuit, and then also is conducive to protect solar module.

Preferred as technique scheme, described thermoelectric generator is the Seebeck effect device.

Preferred as technique scheme, described electronic switch is field effect transistor.

Thermoelectric generator is connected with the gate pole of field effect transistor.

Another object of the present invention is to provide a kind of solar junction box; have the binding post that is electrically connected for solar module, this kind solar junction box inside comprise aforementioned techniques scheme solar module protective circuit bypass diode, be parallel to described bypass diode electronic switch, be thermally coupled in bypass diode and can and turn-off the thermoelectric generator of described electronic switch at another design temperature at the described electronic switch of design temperature conducting.

Because related solar module protective circuit has limited the temperature rise of bypass diode effectively, therefore, is conducive to limit the terminal box temperature rise, improve the reliability of terminal box.

Preferred as technique scheme, thermoelectric generator is the Seebeck effect device.

Preferred as technique scheme, described electronic switch is field effect transistor.

Thermoelectric generator is connected with the gate pole of field effect transistor.

Again another purpose of the present invention is to provide a kind of solar power system, comprises such as the described solar module protective circuit of aforementioned techniques scheme.

Again another purpose of the present invention is to provide a kind of solar power system, comprises such as the described solar junction box of aforementioned techniques scheme.

In sum, the present invention has following beneficial effect: the present invention is simple in structure, and can effectively limit the temperature rise of bypass diode, makes the temperature rise of bypass diode be in all the time below the uniform temperature, thereby reduced the power consumption of protective circuit, improved the reliability of protective circuit; Simultaneously also improve the reliability of solar junction box and solar power system, and be conducive to reduce the overall power of solar power system.

Description of drawings

Fig. 1 is background technology protective circuit schematic diagram;

Fig. 2 is embodiment 1 protective circuit schematic diagram.

Among the figure, 1, cell piece, 2, bypass diode, 3, electronic switch, 4, thermoelectric generator.

Embodiment

Below in conjunction with accompanying drawing the present invention is described in further detail.

This specific embodiment only is explanation of the invention; it is not limitation of the present invention; those skilled in the art can make the modification that does not have creative contribution to present embodiment as required after reading this specification, but as long as all are subject to the protection of Patent Law in claim scope of the present invention.

Embodiment 1: a kind of solar module protective circuit; as shown in Figure 2, comprise thebypass diode 2 in parallel with the solar battery sheet group reversed polarity that is formed by the cell piece 1 that is connected in series, be parallel to describedbypass diode 2 electronic switch 3, be thermally coupled inbypass diode 2 and can and turn-off the thermoelectric generator 4 of described electronic switch 3 at another design temperature at the described electronic switch 3 of design temperature conducting.

Thermoelectric generator 4 is the Seebeck effect device; Electronic switch 3 is field effect transistor; The Seebeck effect device is connected with the gate pole of field effect transistor.

When having cell piece to be blocked,bypass diode 2 conductings, along with uprising ofbypass diode 2 temperature rises, when reaching design temperature, because the Seebeck effect device is thermally coupled inbypass diode 2, so that the Seebeck effect device produces enough electromotive forces, thereby drive the field effect transistor conducting, and then the power consumption of opening between field effect transistor and thebypass diode 2 is distributed, thereby reduce the power consumption ofbypass diode 2, the temperature rise ofbypass diode 2 is reduced, when the temperature rise ofbypass diode 2 is reduced to another design temperature, because the Seebeck effect device is thermally coupled inbypass diode 2, the electromotive force that the Seebeck effect device produces has been not enough to the conducting field effect transistor, thereby so that the field effect transistor shutoff; Yet when the temperature rise ofbypass diode 2 reaches the design temperature that can make the Seebeck effect device produce the electromotive force that makes the field effect transistor conducting again, the again conducting of Seebeck effect device; And then the power consumption of periodically opening between field effect transistor and thebypass diode 2 is distributed, thereby effectively limits the temperature rise ofbypass diode 2, reduces the power consumption of bypass circuit, improves the reliability of protective circuit, and then also is conducive to protect solar module.

Embodiment 2: a kind of solar junction box, have the binding post that is electrically connected for solar module, described solar junction box inside have embodiment 1 solar module protectivecircuit bypass diode 2, be parallel to describedbypass diode 2 electronic switch 3, be thermally coupled inbypass diode 2 and can and turn-off the thermoelectric generator 4 of described electronic switch 3 at another design temperature at the described electronic switch 3 of design temperature conducting; Thermoelectric generator 4 is the Seebeck effect device; Electronic switch 3 is field effect transistor; The Seebeck effect device is connected with the gate pole of field effect transistor.

Embodiment 3: a kind of solar power system comprises embodiment 1 solar module protective circuit.

Embodiment 4: a kind of solar power system comprisesembodiment 2 solar junction boxes.

Claims (8)

1. solar module protective circuit; the bypass diode (2) that the solar battery sheet group reversed polarity that comprises and be comprised of the cell piece that is connected in series (1) is in parallel; it is characterized in that, also comprise the electronic switch (3) that is parallel to described bypass diode (2), be thermally coupled in bypass diode (2) and can and turn-off the thermoelectric generator (4) of described electronic switch (3) at another design temperature at the described electronic switch of design temperature conducting (3).

2. a kind of solar module protective circuit according to claim 1 is characterized in that, described thermoelectric generator (4) is the Seebeck effect device.

3. a kind of solar module protective circuit according to claim 1 is characterized in that, described electronic switch (3) is field effect transistor.

4. solar junction box; has the binding post that is electrically connected for solar module; it is characterized in that described solar junction box inside comprises the bypass diode of solar module protective circuit (2) as claimed in claim 1, is parallel to the electronic switch (3) of described bypass diode (2), is thermally coupled in bypass diode (2) and can turn-offs described electronic switch (3) thermoelectric generator (4) at the described electronic switch of design temperature conducting (3) and at another design temperature.

5. a kind of solar junction box according to claim 4 is characterized in that, described thermoelectric generator (4) is the Seebeck effect device.

6. described a kind of solar junction box according to claim 5 is characterized in that described electronic switch (3) is field effect transistor.

7. a solar power system is characterized in that, comprises such as arbitrary described solar module protective circuit among the claim 1-3.

8. a solar power system is characterized in that, comprises such as arbitrary described solar junction box among the claim 4-6.

Images