CN215072312U

CN215072312U - Photovoltaic bypass protection device

Info

Publication number: CN215072312U
Application number: CN202121541491.2U
Authority: CN
Inventors: 陈斌; 王毅
Original assignee: Yangzhou Yangjie Electronic Co Ltd
Current assignee: Yangzhou Yangjie Electronic Co Ltd
Priority date: 2021-07-07
Filing date: 2021-07-07
Publication date: 2021-12-07
Anticipated expiration: 2031-07-07

Abstract

Photovoltaic bypass protection device. Relate to the photovoltaic field, especially relate to a structural improvement of photovoltaic bypass diode module. The protection device is a shell and a bypass which is arranged on the solar cell module in parallel, a diode module circuit is arranged in the shell, and the diode module circuit comprises a temperature-sensitive normally-open switch, an MOS (metal oxide semiconductor) tube and a diode; the diode module circuit comprises a positive terminal A and a negative terminal B, and the MOS tube is provided with a grid G, a source S and a drain D; the diode is connected in series between a positive terminal a and a negative terminal B. The utility model discloses make this photovoltaic bypass protection device have low temperature rise, high heat escape ability to satisfy current all kinds of heavy current, high voltage photovoltaic cell module's output protection and use.

Description

Photovoltaic bypass protection device

Technical Field

The utility model relates to a photovoltaic field especially relates to a structural improvement of photovoltaic bypass diode module.

Background

The solar cell module is difficult to fall on shields in the long-term use process, the shields form local shadows on the solar cell module, the solar cell module in the series branch under the local shadows is taken as a load and consumes energy generated by other solar cell modules, so that heat is generated to cause local temperature rise, a 'hot spot effect' is formed, when the 'hot spot effect' is serious, welding spots on the solar cell module are melted and damage grid lines, in order to prevent the solar cell from being damaged due to the 'hot spot effect', a bypass diode module is connected in parallel between a positive electrode and a negative electrode of the solar cell module in actual operation, and at least one bypass diode is arranged in the module to prevent the energy generated by the illumination module from being consumed by the shielded modules.

However, with the development of large-sized assemblies in recent years, the half-piece and double-sided double-glass technology is further superimposed, the power of the whole assembly is greatly improved, the 182mm and 210mm silicon chip packaging technology is mature day by day, and the size of the silicon chip is increased day by day, so that a large-current assembly is prevalent, and the conventional common bypass diode module is difficult to adapt to the large-current assembly, so that how to design a high-efficiency, large-current and high-voltage-resistant bypass diode protection module becomes a problem which needs to be solved urgently.

Disclosure of Invention

The utility model discloses to the defect that prior art exists, provide an adjustable, the suitability strong heavy current, high withstand voltage photovoltaic bypass protection device.

The technical scheme of the utility model is that: the protection device is a shell and a bypass which is arranged on the solar cell module in parallel, a diode module circuit is arranged in the shell, and the diode module circuit comprises a temperature-sensitive normally-open switch, an MOS (metal oxide semiconductor) tube and a diode; the diode module circuit comprises a positive terminal A and a negative terminal B, and the MOS tube is provided with a grid G, a source S and a drain D;

the diode is connected in series between a positive terminal a and a negative terminal B,

one end of the temperature-sensitive normally-open switch is connected with the positive electrode end A, the other end of the temperature-sensitive normally-open switch is connected with the source electrode S of the MOS tube, the drain electrode D of the MOS tube is connected with the negative electrode end B,

and the grid G of the MOS tube is connected with the positive electrode terminal A.

The normally-open temperature range of the temperature-sensitive normally-open switch is 50-150 ℃, and the contact resistance is less than 50m omega.

The specification of the MOS tube is adapted to the output voltage and current of the solar cell piece assembly.

The diode specification adapts to the output voltage of the solar cell panel assembly.

The utility model discloses a photovoltaic protection circuit who contains temperature sensitive normally open switch, MOS pipe and diode, this protection circuit setting is in the casing, and the box body is other to connect and form the protection to solar wafer subassembly productivity output at solar wafer subassembly side.

The bypass protection device is used by matching temperature-sensitive normally-open switches of different specifications, the MOS tube and the diode, so that the photovoltaic bypass protection device has low temperature rise and high heat escape capacity, and the output protection application of various current high-current and high-voltage photovoltaic cell assemblies is met.

Drawings

Figure 1 is a schematic diagram of the circuit structure of the present invention,

figure 2 is a schematic view showing the first usage state of the present invention,

FIG. 3 is a schematic view of the second usage state of the present invention;

in the figure, a J-diode, a K-temperature sensitive normally-open switch, an M-solar cell component, an N-light spot, a Q-MOS tube, a G-MOS tube grid, an S-MOS tube source electrode and a D-MOS tube drain electrode.

The arrows in the figure represent the direction of current flow.

Detailed Description

The present invention is further described below with reference to fig. 1-3, wherein the protection device is a housing, and a bypass is arranged in parallel on the solar cell module M, and a diode module circuit is arranged in the housing, and the diode module circuit includes a temperature-sensitive normally open switch K, MOS tube Q and a diode J; the diode module circuit comprises a positive terminal A and a negative terminal B, and the MOS tube Q is provided with a grid G, a source S and a drain D;

the diode J is connected in series between the positive terminal a and the negative terminal B,

one end of the temperature-sensitive normally-open switch K is connected with the positive terminal A, the other end is connected with the source S of the MOS tube Q, the drain D of the MOS tube Q is connected with the negative terminal B,

and the grid G of the MOS tube Q is connected with the positive terminal A.

The normally open temperature range of the temperature-sensitive normally open switch K is 50-150 ℃, and the contact resistance is less than 50m omega. The temperature-sensitive normally-open switches with different contact resistance values can be selected according to the rated current of the whole circuit.

The specification of the MOS tube Q is adapted to the output voltage and current of the solar cell piece assembly M. The gate-source breakdown voltage (BVgs) of the MOS transistor Q is greater than the output voltage (usually > 15v or 18 v) of the cell, the drain-source breakdown voltage (BVds), the threshold voltage (Vth), the conduction voltage drop (Vfsd), and the on-resistance (Ron) of the MOS transistor Q are selectively adapted according to the rated current and the withstand voltage output by the solar cell module M, and the MOS transistor Q is a device well known to those skilled in the art and will not be described herein again.

The specification of the diode J is adapted to the output voltage of the solar cell panel assembly M. The diode J is also selectively adapted according to the rated current and the withstand voltage output by the solar cell module M.

The utility model discloses select the normal operating of suitable temperature sensitive normally open switch K, MOS pipe Q of different specifications and diode J in order to adapt to protection circuit.

As shown in fig. 2, in a normal power generation state, carriers in the solar cell module M are excited by photons, electrons flow to the negative electrode and holes flow to the positive electrode under the action of an internal electric field, so that a potential difference, namely an open-circuit voltage, is generated at both ends, when a loop is formed, a short-circuit current occurs, the potential at a point B is higher than the potential at a point a, and the current flows from a point a to B. For the invention, the diode J is in a reverse cut-off state, the MOS tube G is reversely biased and is in a cut-off state, and the temperature-sensitive normally-open switch K is used for processing a low-temperature region and is in a normally-open state, so that the whole photovoltaic bypass protection device is reversely cut off and does not work.

As shown in fig. 3, the area of the solar cell module M is partially covered by the light spot N to generate the hot spot effect, no matter whether the cell is completely or partially covered; in this state, the battery piece is in a high resistance state, which is equivalent to an open circuit, and the current cannot pass through, and at this time, the current flows through a → the utility model (middle) → B. In the initial stage, the temperature-sensitive normally-open switch K is normally open, so that current flows through the diode J; the diode J generates heat after being conducted, so that the temperature of the whole protection device system is increased, and when the temperature reaches the closing value of the temperature-sensitive normally-open switch K, the temperature-sensitive normally-open switch K is closed; meanwhile, because the MOS tube G is positively biased, the MOS tube Q is conducted, and the other branch (with the extremely low resistance value of about 0.013 omega and the rated current of about 30A) formed by the temperature-sensitive normally-open switch K and the MOS tube Q plays a role in shunting, the current flowing through the diode J is rapidly reduced, and the whole device is cooled; when the temperature is reduced to the starting temperature of the temperature-sensitive switch K, the branch is disconnected, the current flows through the diode J again, the temperature of the whole system is increased again, and the operation is repeated in sequence.

When the hot spot effect is finished, the battery plate recovers to work again, the system recovers to the state shown in fig. 2 at the moment, although the instantaneous temperature-sensitive normally-open switch is still in a closed state, the potential difference between two ends of the instantaneous A, B is changed at the moment, the MOS tube QG pole recovers to a reverse bias state, so that the branch is not conducted, and the circuit is still protected by the reverse cut-off capability of the diode J (the temperature is lower, and the reverse withstand voltage of the diode is still at a high level).

The present invention is not limited to the above embodiments, and based on the technical solutions disclosed in the present invention, those skilled in the art can make some replacements and transformations for some technical features without creative labor according to the disclosed technical contents, and these replacements and transformations are all within the protection scope of the present invention.

Claims

1. The photovoltaic bypass protection device is a shell and a bypass which is arranged on the solar cell module in parallel, and a diode module circuit is arranged in the shell and is characterized in that the diode module circuit comprises a temperature-sensitive normally-open switch, an MOS (metal oxide semiconductor) tube and a diode; the diode module circuit comprises a positive terminal A and a negative terminal B, and the MOS tube is provided with a grid G, a source S and a drain D;

2. The photovoltaic bypass protection device according to claim 1, wherein the normally-on temperature range of the temperature-sensitive normally-on switch is 50-150 ℃, and the contact resistance is less than 50m Ω.

3. The photovoltaic bypass protection device according to claim 1, wherein the MOS transistor specification is adapted to the output voltage and current of the solar cell slice assembly.

4. The photovoltaic bypass protection device according to claim 1, wherein the diode specification is adapted to an output voltage of the solar cell sheet assembly.