CN210780097U - A low-voltage power distribution system - Google Patents

Abstract

The utility model relates to the technical field of low-voltage power distribution, and discloses a low-voltage power distribution system, which comprises two groups of bus modules with the same structure, wherein the two groups of bus modules are connected through a bus-bar connection cabinet, and each group of bus modules comprises a receiving main cabinet, a capacitance cabinet and a wire outlet cabinet; each group of bus modules is connected with a transformer through a receiving main cabinet; a bus connection line is arranged in the bus connection cabinet, a bus is arranged in each group of bus modules, and the buses between the two groups of bus modules are connected through the bus connection line. The utility model discloses can show the control to the electric current of each branch road module, can carry out reactive compensation to the system automatically, improve the power supply quality, set up multiple protection device in distribution system inside, especially also can automatic cutout circuit under switch, circuit breaker safeguard measure failure condition, the at utmost reduces the loss.

Description

A low-voltage power distribution system

technical field

The utility model relates to the technical field of low-voltage power distribution, in particular to a low-voltage power distribution system.

Background technique

With the continuous expansion of the power grid scale and the gradual increase in user demand, various types of low-voltage power distribution systems have also appeared in the market. Most low-voltage power distribution systems adopt the structure of two incoming lines and one bus tie. Two transformers are used to supply power to the two bus bars, and the two bus bars are connected through a bus tie switch. An intelligent acquisition control module is added to the electrical system, and the electric energy is distributed intelligently through the intelligent acquisition control module, but the existing technology still has the following problems:

1. When the circuit is working normally, the current information of each circuit cannot be observed in time.

2. The protection measures are not enough. When a fault occurs in the circuit, once a certain circuit breaker fails, it will cause serious consequences.

3. Insufficient reactive power, the voltage drop of transmission lines and transformers increases, the quality of power supply decreases, and even threatens the safe operation of the system.

Utility model content

In view of the deficiencies in the prior art, the purpose of the present invention is to provide a low-voltage power distribution system, the purpose of which is to solve the problems of untimely monitoring information and insufficient protection measures in the low-voltage power distribution system, and to effectively improve the The reactive power of the low-voltage power distribution system is insufficient, and the quality of power supply is improved.

In order to achieve the above object, the utility model provides the following technical solutions:

A low-voltage power distribution system includes a first transformer, a second transformer, a first busbar module, a bus-connecting cabinet, and a second busbar module. The transformer 1 and the transformer 2 are located on both sides of the low-voltage power distribution system, and are respectively connected with the main receiving cabinet AA1 and the receiving main cabinet AA11 softly to supply power for the first busbar module and the second busbar module; the first busbar module Including receiver cabinet AA1, capacitor cabinet AA2, capacitor cabinet AA3, outlet cabinet AA4, outlet cabinet AA5, the receiver cabinet AA1, capacitor cabinet AA2, capacitor cabinet AA3, outlet cabinet AA4, outlet cabinet AA5 are connected sequentially from left to right to the first busbar of the first busbar module; the second busbar module has the same structure as the first busbar module, and the busbar connection between the first busbar module and the second busbar module passes through the busbar connection cabinet AA6 line connection.

Further, the other end of the main receiving cabinet AA1 is connected to the first transformer, and is responsible for transmitting the electric energy of the first voltage transformer to the first bus.

The main receiving cabinet AA1 is connected to the busbar through a receiving bus line, and the receiving bus line includes the first incoming switch and the current transformer connected to the first incoming switch, and is responsible for controlling the on-off of the entire first bus module power. . Under normal conditions of the circuit, the first incoming line switch is closed, the current transformer transmits current information, and the first incoming line switch will be automatically disconnected once a fault occurs in the circuit.

Further, the capacitor cabinet AA2 and the capacitor cabinet AA3 are connected to the busbar through a capacitor line, and the capacitor line is provided with an automatic compensation controller, a contactor, a thermal relay, and a capacitor, which are sequentially connected in series in the circuit. , After the automatic compensation controller detects the sampling signal, it selects the required capacitor and controls the contactor to close, the capacitor works, and the circuit is reactive power compensation, reducing the loss of the transmission line of the first transformer and the first bus module, and improving the power supply efficiency. Improve power supply environment, improve power supply quality and system stability.

The capacitor cabinet AA2 and the capacitor cabinet AA3 are internally provided with lightning arresters with a model of FYS-0.22*3, which are used to protect the insulation of the electrical equipment of the system from being damaged by atmospheric overvoltage and operating voltage.

Further, the outlet cabinet AA4 and the outlet cabinet AA5 are both connected to the busbar through the outlet line, and are responsible for distributing the electric energy to each power consumption place.

The above-mentioned capacitor cabinet AA2, capacitor cabinet AA3, outlet cabinet AA4, and outlet cabinet AA5 all contain circuit breakers and current transformers connected to the circuit breakers. The circuit is cut off. The current transformer has three windings, and the signal of the output current is transmitted to the multi-function meter for display. Once the circuit fails, the circuit breaker will automatically cut off immediately. If the circuit breaker is still not cut off under high current, the current transformer will When a large current is detected, it will automatically cut off to achieve double protection and reduce circuit damage.

Further, a bus tie line of the bus tie cabinet AA6 contains a bus tie switch and a current transformer connected with the bus tie switch, and the bus tie switch controls the on-off of the first bus module and the second bus module, so The current transformer realizes the protection of the bus tie switch and transmits the current information to the multi-function meter.

Further, the other end of the main receiving cabinet AA11 is connected to the second transformer, and is responsible for transmitting the electric energy of the second transformer to the second bus. The structure of the second busbar module is the same as that of the first busbar module, and the layout positions are in a symmetrical relationship with respect to the bus coupling cabinet, which will not be repeated here.

Further, the first incoming line switch, the second incoming line switch and the bus tie switch are provided with reliable mechanical and electrical interlocking (interlocking mode of three locks and two keys) to ensure that at most two of the three switches are closed at the same time.

Compared with the prior art, the beneficial effects of the present utility model are:

1. The present utility model provides a low-voltage power distribution system, which can continuously and stably provide voltage for the load under normal conditions of the circuit, and at the same time, the multi-function meter can be used to display the current condition of each branch, which makes monitoring more efficient. Intuitive.

2. In a low-voltage power distribution system provided by the present invention, an MNS system switch cabinet is used, and an independent PE grounding protection system is arranged in the cabinet and runs through the entire device. In addition, a variety of protection devices are set up in the low-voltage power distribution system, which can avoid the impact on the entire circuit when a fault occurs somewhere in the circuit to the greatest extent, and reduce the scope of the accident.

3. In the low-voltage power distribution system provided by the utility model, the circuit is effectively compensated for reactive power, the loss of the transformer and the transmission line is reduced, the power supply efficiency is improved, the power supply environment is improved, the power supply quality and the system stability are improved.

Description of drawings

Figure 1 is a schematic diagram of the structure of a low-voltage power distribution system.

Figure 2 is a circuit diagram of a low-voltage power distribution system.

Figure 3 is the wiring diagram of the capacitor cabinet.

Figure 4. The wiring diagram of the current transformer and the multi-function meter.

Detailed ways

The technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the implementations. example. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention.

As shown in FIG. 1 , it is a schematic structural diagram of a low-voltage power distribution system provided in an embodiment of the present invention, including a transformer 1, a transformer 2, a first busbar module, a bus tie cabinet, and a second busbar module. Transformer 1 and transformer 2 are located on both sides of the low-voltage power distribution system. The first busbar module includes the main receiving cabinet AA1, the capacitor cabinet AA2, the capacitor cabinet AA3, the outlet cabinet AA4, and the outlet cabinet AA5. The second busbar module includes the outlet cabinet AA7 and the outlet wire. Cabinet AA8, capacitor cabinet AA9, capacitor cabinet AA10, receiving main cabinet AA11, the first busbar module and the second busbar module are connected through bus coupling cabinet AA6.

As shown in FIG. 2, it is a circuit diagram of a low-voltage power distribution system provided in an embodiment of the present invention. One end of the transformer is softly connected to the main receiving cabinet AA1, which is responsible for supplying power to the first busbar module, and the other end is grounded for protection. The second end of the transformer is softly connected to the main cabinet AA11, which is responsible for supplying power to the second busbar module, and the other end is grounded.

The other end of the main cabinet AA1 is connected to the first bus, including the first incoming switch QF1, current transformer, and fuse. The first incoming switch QF1 and the current transformer are connected to the first bus in series, and the two fuses are grounded in series protection, the first incoming switch QF1 controls the total on-off of the entire first bus module, and the current transformer transmits the current information to the multi-function meter. In a normal state, the first incoming switch QF1 is in a closed state. Once a fault occurs in the first busbar module, the first incoming switch QF1 is automatically disconnected.

Capacitor cabinet AA2 is connected to the first bus, including circuit breaker QF11, current transformer, automatic compensation controller QF12, contactor, thermal relay, capacitor, and connected in sequence, as shown in Figure 3, fuse grounding and current mutual inductance The automatic compensation controller selects the model JKWA1-18JT (control 18-way contactor), and the K1~K8 ports of the automatic compensation controller are connected to the 8 contactors of the capacitor cabinet AA2, capacitor cabinet AA9, and capacitor cabinet AA10. Under normal working conditions, the circuit breaker QF11 is closed, and the current transformer transmits the current information to the multi-function meter to display the current information of the capacitor cabinet. After the automatic compensation controller detects the sampling signal, it selects the required capacitor and controls the contactor to close, the capacitor The work compensates the reactive power of the transformer one and the first busbar module, improves the power factor and improves the power supply quality. When the circuit fails, the circuit breaker QF11 and the automatic compensation controller QF12 are disconnected, and the thermal relay will delay the disconnection of the contactor, reducing the impact of the large current impact of the circuit on the capacitor and preventing damage to the circuit. Capacitor cabinet AA3, capacitor cabinet AA9, and capacitor cabinet AA10 have the same composition as capacitor cabinet AA2.

The outlet cabinet AA4 is connected to the first bus, and each outlet cabinet includes two lines, which mainly realize the distribution of electric energy. Each line includes a circuit breaker and a current transformer, which are connected in sequence. When the circuit is working normally, the circuit breaker is closed, each branch is connected to the load to realize the distribution of electric energy, and the current transformer is responsible for transmitting the electric energy to the multi-function meter to display the current information. When the circuit fails, the circuit breaker is automatically disconnected. Once the circuit breaker fails, the current transformer will automatically cut off the circuit when it detects a large current to prevent serious consequences. Outlet cabinet AA5, outlet cabinet AA7, outlet cabinet AA8 have the same structure as outlet cabinet AA4.

The bus tie cabinet AA6 is connected with the first bus module and the second bus module, and realizes the connection or on-off of the current between the first bus module and the second bus module, including the bus tie switch QF3, the current transformer, the bus tie switch QF3 and the current mutual inductance One end of the series connection is connected to the first bus bar, and the other end is connected to the second bus bar. When the circuit is working normally, the bus tie switch QF3 is disconnected, and the transformer 1 and the transformer 2 supply power to the first bus tie module and the second bus tie module respectively. If the first busbar module fails, the first incoming switch QF1 is disconnected and the bus tie switch QF3 is closed, and the second transformer can continue to supply power to the first busbar module to reduce the loss caused by the failure. The current transformer can realize the protection of the failure of the bus tie switch, and can also transmit the current information to the multi-function meter. The failure of the second busbar module is the same as above.

As shown in Figure 4, it is the wiring diagram of the current transformer and the multi-function meter. The model of the multi-function meter is JH850. The No. 5 port of the multi-function meter is connected to the A phase of the current transformer, and the No. 7 port of the multi-function meter is connected to The B phase of the current transformer is connected, the No. 9 port of the multi-function meter is connected to the C phase of the current transformer, the No. 6, 8, and 10 ports of the multi-function Ports 1, 2, and 3 of the power meter are respectively connected with three fuses and connected to the three-phase power lines of L1, L2, and L3 to realize overcurrent protection of the multi-function meter. Ports 4 and 12 of the multi-function meter are connected to the neutral line. .

In specific implementation, when the circuit is working normally, the first incoming switch QF1 and the second incoming switch QF2 are closed, the bus tie switch QF3 is disconnected, the transformer 1 supplies power to the first bus module, and the transformer 2 supplies power to the second bus module. The receiving cabinet is responsible for transmitting electrical energy, the capacitor cabinet automatically compensates the circuit for reactive power, the outlet cabinet distributes electrical energy, and the multi-function meter of each branch displays the current information of the branch. When the circuit is faulty, if the first busbar module fails, the first incoming switch QF1 is automatically disconnected immediately, the circuit breaker of the branch where the fault occurs is disconnected, the busbar switch QF3 is automatically closed, and the second transformer to the first busbar module The other parts of the power supply, which can minimize the loss of failure. When the second busbar module fails, the second incoming switch QF2 is automatically disconnected immediately, the circuit breaker of the branch where the fault occurs is disconnected, the busbar switch QF3 is automatically closed, and the transformer supplies power to other parts of the first busbar module. In the event of a fault, if the circuit breaker or incoming line switch does not trip and cut off the circuit, the current transformer connected to it will automatically cut off the circuit when it detects a large current, so as to avoid causing greater losses.

In a low-voltage power distribution system of the present invention, each branch of each cabinet is provided with an independent protection device. Equipped with a current transformer, the set current transformer can not only realize the failure protection of the circuit breaker, the first incoming switch, the second incoming switch and the bus tie switch, but also transmit the current information to the multi-function meter for timely monitoring of each The branch current information is displayed. In addition, the utility model adopts the MNS system switch cabinet, and an independent PE grounding protection system is arranged in the cabinet and runs through the whole device. The fuse grounding protection is provided in the capacitor cabinet, which can effectively protect the low-voltage power distribution system. Once the circuit fails, the system can minimize the failure loss.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which the present invention belongs. The terms used in the description of the present invention herein are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

The above description is a detailed description of the preferred feasible embodiments of the present utility model, but the embodiments are not intended to limit the scope of the patent application of the present utility model. All should belong to the scope of the patent covered by this utility model.

Claims (5)

1. A low-voltage power distribution system is characterized by comprising two groups of bus modules with the same structure, wherein the two groups of bus modules are connected through a bus connection cabinet, and each group of bus modules comprises a receiving main cabinet, a capacitance cabinet and an outgoing line cabinet; each group of bus modules is connected with a transformer through a receiving main cabinet; be provided with a mother in the mother allies oneself with the circuit in the cabinet, all be provided with a generating line in each group's bus module, the generating line between two sets of bus modules passes through mother allies oneself with the line connection, be provided with a mother on the mother allies oneself with the circuit and allies oneself with switch and a current transformer, current transformer is connected with a multifunctional electric meter, realizes the measurement to the electric current on the mother allies oneself with the circuit.

2. A low voltage power distribution system according to claim 1 wherein the transformer is flexibly connected to the slave unit, and wherein the transformer supplies power to the bus bar module during normal operation of the circuit.

3. The low voltage power distribution system of claim 1, wherein the controlled main cabinet is connected to the bus via a controlled bus, the controlled bus comprising a first incoming switch and a current transformer connected to the incoming switch, the current transformer providing fault protection for the incoming switch and transmitting current information to the multifunctional power meter for measurement of the current information of the controlled main cabinet.

4. The low voltage power distribution system of claim 1 wherein the capacitor box is connected to the bus by a capacitor circuit having an automatic compensation controller, a contactor, a thermal relay, and a capacitor connected in series in order to achieve reactive compensation of the transmission line and the transformer of the bus module.

5. The low-voltage power distribution system according to claim 1, wherein the outlet cabinet is connected to the bus through an outlet line, the outlet line comprises a circuit breaker and a current transformer connected to the circuit breaker, when the circuit is in normal operation, the outlet line distributes electric energy, and the current transformer transmits information to the multifunctional electric meter to display current information; when the circuit broke down, the circuit breaker breaks off immediately, cuts off the circuit, if the circuit breaker did not break off, will automatic disconnection when electric transformer detected the heavy current, avoids causing bigger loss.

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