TBEA compensation soft starting device used for large power cage type motor

Abstract

The invention provides a TBEA compensation soft starting device used for a large power cage type motor, and belongs to the technical field of large power cage type motor soft staring. The soft starting device mainly solves the problems of switch-on surging impact and by-pass jumping impact currents of autotransformer starting, and is mainly characterized in that an iron core shaped like a Chinese character 'tian' is divided into an autotransformer structure and an electric reactor structure, and is provided with an independent auto winding and an independent reactance winding. A first external connection port, a second external connection port, a third external connection port and a fourth external connection port are respectively connected with a self-excitation starting breaker, a by-pass self-excitation winding breaker, a starting compensation breaker, a connection breaker and one end of a series excitation control breaker, a starting idle work compensation unit is serially connected between the other end of the starting compensation breaker and a star point common terminal, the other end of the connection breaker is connected with the motor and one end of a by-pass operation breaker, and the other end of the by-pass operation breaker is connected with a bus. The soft starting device has the advantages of weakening surging at an auto starting moment and restraining by-pass phase step impact, and is mainly used for the large power cage type motor.

Description

technical field

[0001] The invention belongs to the technical field of cage-type high-power motor soft start. In particular, it relates to a main circuit for a high-power cage-type special-type transformer compensation soft starter. Background technique

[0002] At present, with the rapid expansion of my country's industrialization process, in key energy-consuming enterprises in my country's secondary industrial structure (such as steel, chemical industry, etc.), high-power motors with a high voltage of 10,000kW or more are used more and more frequently. The strength of the power grid (minimum short-circuit capacity), tolerance margin (voltage fluctuation range), and disturbance intensity (reactive starting current impact) are all a strong test. There are fewer and fewer forms that can be realized for power cage motors. Whether it is possible to find a starting method that minimizes the reactive power inrush current at the moment of motor starting and has less fluctuations in...

Examples

Embodiment 1

[0019] Example 1 as figure 1shown. The main busbar of the power grid is connected to the input terminal of the incoming line circuit breaker QF7 through the distribution transformer T2, and the outgoing line end of the incoming line circuit breaker QF7 is connected to the 10 (6) kV starting circuit busbar, and then connected to the self-excited starting circuit breaker after the starting circuit busbar is energized The incoming terminal of QF3 of the self-excited starting circuit breaker, and the outgoing terminal of QF3 of the self-excited starting circuit breaker are connected to the external interface ① of the special type self-excited starting transformer T1. The interface ① of the special self-excited starting transformer T1 is internal and connected to two independent internal windings, one of which is connected to the internal independent autotransformer winding L1, and the other is connected to the internal independent reactor characteristic winding L2. The autotransf...

Embodiment 2

[0024] Example 2 as figure 2 shown. The difference from Embodiment 1 is that an in-situ compensation circuit composed of an in-situ compensation circuit breaker QF8 and an in-situ compensation capacitor C2 connected in series is connected between the external output port ② of the special-type self-excited starting transformer T1 and the star point common terminal.

[0025] The working principle of embodiment 2 of the present invention is:

[0026] The starting circuit of the main circuit step-down current limiting compensation is to connect the main circuit incoming circuit breaker QF7, the main bus of the power grid supplies power to the 10 (6) kV starting circuit bus through the distribution transformer T2 and the incoming circuit breaker QF7, and the series excitation control is connected The circuit breaker QF1 short-circuits the common winding of the special-type starting transformer T1 to form a star point, and then connects the self-excited starting circuit breaker QF...

Embodiment 3

[0030] Example 3 as image 3 , Figure 4 shown. It mainly introduces the internal structure of the special self-excited starting transformer T1. The input part of the winding wiring schematic diagram of the special self-excited starting transformer comes from the three phases A, B and C of the external interface ①, and the winding of the special self-excited starting transformer passes through three The phase-independent autocoupling windings L1a, L1b, L1c are connected to one end of the three-phase external interface ② of the special type self-excited starting transformer through the self-excitation tap of the internal manual tap changer K to select the J1 contact, and the three outputs of the external interface ② are respectively Output U1, V1, W1 three-phase, special-type self-excited starting transformer winding through three-phase independent reactor windings L2a, L2b, L2c through the three outputs of the external interface ④ respectively output U2, V2, W2 three-phase, s...

technical field

[0001] The invention belongs to the technical field of cage-type high-power motor soft start. In particular, it relates to a main circuit for a high-power cage-type special-type transformer compensation soft starter. Background technique

[0002] At present, with the rapid expansion of my country's industrialization process, in key energy-consuming enterprises in my country's secondary industrial structure (such as steel, chemical industry, etc.), high-power motors with a high voltage of 10,000kW or more are used more and more frequently. The strength of the power grid (minimum short-circuit capacity), tolerance margin (voltage fluctuation range), and disturbance intensity (reactive starting current impact) are all a strong test. There are fewer and fewer forms that can be realized for power cage motors. Whether it is possible to find a starting method that minimizes the reactive power inrush current at the moment of motor starting and has less fluctuations in...

Examples

Embodiment 1

[0019] Example 1 as figure 1shown. The main busbar of the power grid is connected to the input terminal of the incoming line circuit breaker QF7 through the distribution transformer T2, and the outgoing line end of the incoming line circuit breaker QF7 is connected to the 10 (6) kV starting circuit busbar, and then connected to the self-excited starting circuit breaker after the starting circuit busbar is energized The incoming terminal of QF3 of the self-excited starting circuit breaker, and the outgoing terminal of QF3 of the self-excited starting circuit breaker are connected to the external interface ① of the special type self-excited starting transformer T1. The interface ① of the special self-excited starting transformer T1 is internal and connected to two independent internal windings, one of which is connected to the internal independent autotransformer winding L1, and the other is connected to the internal independent reactor characteristic winding L2. The autotransf...

Embodiment 2

[0024] Example 2 as figure 2 shown. The difference from Embodiment 1 is that an in-situ compensation circuit composed of an in-situ compensation circuit breaker QF8 and an in-situ compensation capacitor C2 connected in series is connected between the external output port ② of the special-type self-excited starting transformer T1 and the star point common terminal.

[0025] The working principle of embodiment 2 of the present invention is:

[0026] The starting circuit of the main circuit step-down current limiting compensation is to connect the main circuit incoming circuit breaker QF7, the main bus of the power grid supplies power to the 10 (6) kV starting circuit bus through the distribution transformer T2 and the incoming circuit breaker QF7, and the series excitation control is connected The circuit breaker QF1 short-circuits the common winding of the special-type starting transformer T1 to form a star point, and then connects the self-excited starting circuit breaker QF...

Embodiment 3

[0030] Example 3 as image 3 , Figure 4 shown. It mainly introduces the internal structure of the special self-excited starting transformer T1. The input part of the winding wiring schematic diagram of the special self-excited starting transformer comes from the three phases A, B and C of the external interface ①, and the winding of the special self-excited starting transformer passes through three The phase-independent autocoupling windings L1a, L1b, L1c are connected to one end of the three-phase external interface ② of the special type self-excited starting transformer through the self-excitation tap of the internal manual tap changer K to select the J1 contact, and the three outputs of the external interface ② are respectively Output U1, V1, W1 three-phase, special-type self-excited starting transformer winding through three-phase independent reactor windings L2a, L2b, L2c through the three outputs of the external interface ④ respectively output U2, V2, W2 three-phase, s...

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