CN210156931U - Distributed photovoltaic grid-connected power generation system with electrical interlocking device - Google Patents

Abstract

The utility model discloses a distributed photovoltaic grid-connected power generation system with an electrical interlocking device, which comprises a low-voltage photovoltaic input cabinet, a grid-connected transformer and a high-voltage grid-connected cabinet connected in sequence; A low-voltage circuit breaker is arranged, a high-voltage vacuum circuit breaker is arranged on the line in the high-voltage grid-connected cabinet, and an electrical interlocking device is arranged between the low-voltage circuit breaker and the high-voltage vacuum circuit breaker to link the two. In this technical solution, an electrical interlocking device is arranged in the opening and closing control circuit of the high and low circuit breakers. When the power grid is faulty or interrupted, after the protection of the high-voltage side circuit breaker trips, the grid-connected low-voltage side circuit breaker is guaranteed to be opened, ensuring that the photovoltaic The grid-connected power generation system cannot continue to supply power to the load independently, thus preventing the "islanding effect" more effectively. This solution can be realized only by adding electrical interlocking wiring to the high and low voltage circuit breakers in the high and low voltage electrical parts of the 10kV distributed photovoltaic grid-connected power generation system, which has high economic benefits.

Description

A distributed photovoltaic grid-connected power generation system with electrical interlocking device

technical field

The utility model relates to the field of photovoltaic grid-connected power generation systems, in particular to a distributed photovoltaic grid-connected power generation system with an electrical interlocking device.

Background technique

Energy conservation and emission reduction, green environmental protection is a basic national policy, vigorously promoting energy conservation and emission reduction and in-depth development of green energy is the guarantee for the sustainable development of the national economy. As a primary energy source, solar energy is also a renewable energy source. It is rich in resources and can be used free of charge without environmental pollution. Its research and application have been highly valued by the country, and a series of preferential policies and regulations have been issued to promote the application of solar power generation. The application of distributed photovoltaic grid-connected power generation systems in the power grid is also becoming more and more extensive. When this distributed photovoltaic grid-connected power generation system is connected to a 10kV distribution network, the high-voltage side generally uses grid-connected protection devices for grid-connected access. and decoupling. In the event of grid failure or interruption, the solar photovoltaic power generation system continues to independently supply power to the load, a phenomenon called "islanding effect". If this phenomenon occurs, the safety of maintenance personnel will be threatened when repairing grid faults.

Utility model content

In order to solve the above technical problems, the purpose of the present invention is to provide a distributed photovoltaic grid-connected power generation system that prevents islanding effect.

The technical scheme adopted by the utility model is as follows:

A distributed photovoltaic grid-connected power generation system with an electrical interlocking device, comprising a low-voltage photovoltaic incoming line cabinet, a grid-connected transformer and a high-voltage grid-connected cabinet connected in sequence;

A low-voltage circuit breaker is installed on the line in the low-voltage photovoltaic incoming cabinet, a high-voltage vacuum circuit breaker is installed on the line in the high-voltage grid-connected cabinet, and a two-circuit breaker is installed between the low-voltage circuit breaker and the high-voltage vacuum circuit breaker. The electrical interlocking device that is linked with each other.

Further, the electrical interlocking device comprises an auxiliary contact in the opening position of the high-voltage vacuum circuit breaker and an opening coil of the low-voltage circuit breaker connected in series, wherein when the vacuum circuit breaker is in the opening position, the auxiliary contact in the opening position When the vacuum circuit breaker is in the closed position, the auxiliary contact in the open position is in the normally open state; the low-voltage circuit breaker opening coil is used to drive the low-voltage circuit breaker to open after being energized.

Further, the electrical interlocking device also includes a first miniature circuit breaker connected between the control power supply and the auxiliary contact at the opening position, a second miniature circuit breaker connected between the control power supply and the opening coil of the low-voltage circuit breaker. MCB.

Beneficial effects of the present utility model: In this technical scheme, an electrical interlocking device is arranged in the opening and closing control loop of the high and low circuit breakers. When the power grid fails or is interrupted, the high voltage side circuit breaker is protected and tripped to ensure that the low voltage side of the grid is connected. The circuit breaker is opened to ensure that the photovoltaic grid-connected power generation system cannot continue to supply power to the load independently, thereby more effectively preventing the "islanding effect". This solution can be realized only by adding electrical interlocking wiring to the high and low voltage circuit breakers in the high and low voltage electrical parts of the 10kV distributed photovoltaic grid-connected power generation system, which has high economic benefits.

Description of drawings

The specific embodiments of the present utility model will be further described below with reference to the accompanying drawings.

Fig. 1 is the framework diagram of the distributed photovoltaic grid-connected power generation system of the present invention;

Figure 2 is an electrical diagram of the electrical interlocking device of the present invention.

Detailed ways

As shown in FIG. 1 , it is a distributed photovoltaic grid-connected power generation system with an electrical interlock device of the present invention, which includes a low-voltage photovoltaic incoming cabinet 100, a grid-connected transformer 200 and a high-voltage grid-connected cabinet 300 connected in sequence;

A low-voltage circuit breaker QF1 is provided on the line in the low-voltage photovoltaic incoming cabinet 100, and a high-voltage vacuum circuit breaker DL is provided on the line in the high-voltage grid-connected cabinet 300. The low-voltage circuit breaker QF1 and the high-voltage vacuum circuit breaker DL An electrical interlocking device for interlocking the two is arranged between them.

The principle of this technical solution is to design an electrical interlocking device in the opening and closing control circuit of the high and low voltage side circuit breakers in the photovoltaic grid-connected power generation system to ensure that when the power grid fails or is interrupted, the DL protection of the vacuum circuit breaker on the high voltage side is tripped. After that, the low-voltage circuit breaker QF1 on the low-voltage side of the grid must be opened to prevent the "islanding effect".

As a specific implementation of this embodiment, as shown in FIG. 2 , the electrical interlocking device includes a series-connected auxiliary contact in the opening position of the high-voltage vacuum circuit breaker DL, and the opening coil of the low-voltage circuit breaker QF1. When the circuit breaker DL is in the open position, the auxiliary contact DL in the open position is in a normally closed state; when the vacuum circuit breaker DL is in the closed position, the auxiliary contact DL in the open position is in a normally open state; the After the low-voltage circuit breaker QF1 opening coil is energized, it is used to drive the low-voltage circuit breaker QF1 to open.

During normal operation, the high-voltage side vacuum circuit breaker DL is in the closed state, the auxiliary contact at the opening position of the vacuum circuit breaker DL is disconnected, the high-voltage blocking circuit does not operate, and the low-voltage circuit breaker QF1 opening circuit is disconnected; when the power grid fails or In the case of abnormal conditions after interruption, the vacuum circuit breaker DL is in the protection opening state, the contact at the opening position becomes normally closed, the high-voltage blocking circuit operates, the low-voltage circuit breaker opening electrical circuit is connected, and the circuit breaker QF1 is disconnected;

In addition, the electrical interlocking device further includes a first miniature circuit breaker F1 connected between the control power supply and the auxiliary contact at the opening position, a first miniature circuit breaker F1 connected between the control power supply and the opening coil of the low-voltage circuit breaker QF1 The second miniature circuit breaker F2.

The above are only the preferred embodiments of the present invention, and the present invention is not limited to the above-mentioned embodiments, as long as the technical solutions that achieve the purpose of the present invention by basically the same means fall within the protection scope of the present invention.

Claims (3)

1. A distributed photovoltaic grid-connected power generation system with an electrical interlocking device is characterized in that: it comprises a low-voltage photovoltaic incoming line cabinet, a grid-connected transformer and a high-voltage grid-connected cabinet connected in sequence; A low-voltage circuit breaker is installed on the line in the low-voltage photovoltaic incoming cabinet, a high-voltage vacuum circuit breaker is installed on the line in the high-voltage grid-connected cabinet, and a two-circuit breaker is installed between the low-voltage circuit breaker and the high-voltage vacuum circuit breaker. The electrical interlocking device that is linked with each other. 2 . A distributed photovoltaic grid-connected power generation system with an electrical interlocking device according to claim 1 , wherein the electrical interlocking device comprises a series-connected auxiliary contact for the internal opening position of the high-voltage vacuum circuit breaker. 3 . , low-voltage circuit breaker opening coil, wherein, when the vacuum circuit breaker is in the opening position, the auxiliary contact in the opening position is normally closed; when the vacuum circuit breaker is in the closing position, the auxiliary contact in the opening position is in a normally closed state. The point is normally open; the low-voltage circuit breaker opening coil is used to drive the low-voltage circuit breaker to open after being energized. 3. A distributed photovoltaic grid-connected power generation system with an electrical interlocking device according to claim 2, wherein the electrical interlocking device further comprises an auxiliary contact connected between the control power supply and the opening position A first miniature circuit breaker between them, and a second miniature circuit breaker connected between the control power supply and the opening coil of the low-voltage circuit breaker.

Images