High-pressure liquid resistance soft start and solid soft start redundant start motor system

Abstract

The utility model discloses a high-pressure liquid resistance soft start and solid soft start redundant start motor system, relates to the technical field of motor start circuits, and solves the problems of limited start performance, great environmental influence, troublesome maintenance, high cost and the like in the existing start mode. Comprising a switching cabinet and a plurality of wire inlet cabinets, the wire inlet cabinets are connected to corresponding motors respectively, the switching cabinet comprises a plurality of switching circuit breakers, the other ends of the motors are connected to corresponding star point cabinets, liquid resistance starting cabinets and corresponding switching circuit breakers, and the other ends of the switching circuit breakers are connected to a high-voltage solid-state soft start cabinet. An old liquid resistance cabinet system is reserved, the high-voltage solid-state soft starter is arranged, more accurate and stable starting control is provided, the high-voltage solid-state soft starter serves as standby redundant equipment, the maximum benefit is achieved, and the effects that the liquid resistance cabinet is reserved and the high-voltage solid-state soft starter coexists with a new high-voltage solid-state soft starter are achieved.

Description

Technical Field

[0001] This utility model relates to the field of motor starting circuit technology, and in particular to a redundant starting motor system of high-pressure liquid resistance soft starter and solid-state soft starter. Background Technology

[0002] As enterprises increase their production demands, the requirements for large electrical equipment are becoming increasingly stringent. For example, the original fan starting method was hydraulic resistance starting, with two 6KV--3200KW hydraulic resistance cabinets, two high-voltage incoming line cabinets, two star point cabinets, and two high-voltage motors. The control method was as follows: the two hydraulic resistance cabinets used a one-to-one control method to control the two fan motors respectively.

[0003] However, existing starting methods have many drawbacks: ① Limited starting performance: Starting parameters are adjusted by changing the liquid resistance, but this adjustment is difficult to be precise, resulting in large fluctuations in starting current. This not only impacts the power grid but may also cause unstable motor starting, affecting equipment lifespan; ② High susceptibility to environmental influences: The internal liquid resistance characteristics are significantly affected by environmental factors; if the temperature is too low, the electrolyte is prone to solidification, leading to abnormal resistance changes and affecting the starting effect; if the humidity is too high, the number of starts is limited, and it is easy to cause corrosion of the cabinet and electrodes, reducing equipment reliability; ③ Troublesome and costly maintenance: The electrolyte level and concentration need to be checked regularly, and timely replenishment and replacement are required. The electrodes also need to be cleaned and maintained regularly, consuming manpower and resources; once components are damaged, such as liquid leakage or resistor box failure, repair is difficult and costly.

[0004] In addition, the high starting current causes the temperature of the liquid resistance cabinet to rise, limiting the number of starts. In particular, during the dynamic balancing of the fan, multiple starts may be required, but the time interval between two starts is relatively long when using a liquid resistance cabinet, which seriously affects the resumption of production. Utility Model Content

[0005] The purpose of this invention is to provide a redundant starter motor system that combines high-pressure liquid resistance soft starter and solid-state soft starter. This system retains the old liquid resistance cabinet system while also incorporating a high-pressure solid-state soft starter to provide more precise and stable start control. By using the liquid resistance cabinet as a backup redundant device, the system maximizes efficiency and achieves coexistence between the liquid resistance cabinet and the new high-pressure solid-state soft starter.

[0006] The above-mentioned technical objective of this utility model is achieved through the following technical solution:

[0007] A redundant starting motor system for high-voltage hydraulic resistance soft starter and solid-state soft starter includes a switching cabinet and several incoming line cabinets. The switching cabinet includes several switching circuit breakers. The incoming line cabinets are respectively connected to the corresponding motors. The other end of the motor is connected to the corresponding star point cabinet, hydraulic resistance starting cabinet and corresponding switching circuit breaker. The other end of each switching circuit breaker is connected to the high-voltage solid-state soft starter cabinet. The motor is started through the hydraulic resistance starting cabinet or the high-voltage solid-state soft starter cabinet and runs at full voltage through the star point cabinet.

[0008] Furthermore, the incoming line cabinet includes an incoming line cabinet No. 1 and an incoming line cabinet No. 2, which are respectively connected to motor No. 1 and motor No. 2. The switching cabinet includes a first switching circuit breaker and a third switching circuit breaker. The other end of motor No. 1 is connected to the first star point cabinet, the first hydraulic resistance starter cabinet and the first switching circuit breaker, and the other end of motor No. 2 is connected to the second star point cabinet, the second hydraulic resistance starter cabinet and the third switching circuit breaker.

[0009] Furthermore, the No. 1 incoming line cabinet includes a first incoming line circuit breaker, and the No. 2 incoming line cabinet includes a second incoming line circuit breaker.

[0010] Furthermore, the first liquid resistance starter cabinet includes a first liquid circuit breaker and a first water resistor, and the second liquid resistance starter cabinet includes a third liquid circuit breaker and a second water resistor.

[0011] Furthermore, the first star point cabinet includes a second liquid interrupter, and the second star point cabinet includes a fourth liquid interrupter.

[0012] Furthermore, the first and third switching circuit breakers are protected by an interlocking device to prevent them from closing simultaneously.

[0013] Furthermore, the high-voltage solid-state soft starter cabinet includes an internal thyristor valve assembly.

[0014] Furthermore, the switching cabinet also includes a live display.

[0015] In summary, this utility model has the following beneficial effects:

[0016] The innovative starting method that retains the old liquid resistance cabinet and coexists with the new high-voltage solid-state soft starter is of great practical significance.

[0017] Although the old liquid resistance cabinet has its shortcomings, it is a key piece of equipment in past production, carrying historical operating data. It can be used as an emergency backup starting device to ensure production continuity when the new soft starter fails or is under maintenance.

[0018] The old liquid resistance cabinet was retained, which saved on dismantling and disposal costs;

[0019] The new high-voltage solid-state soft starter provides more precise and stable start control. The coexistence of the two can meet the complex production needs of daily life and ensure production operation in special circumstances, maximizing the utilization value of equipment and reducing overall operational risks. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of a high-pressure liquid resistance soft starter and solid-state soft starter redundant starter motor system according to this utility model;

[0021] Figure 2 This is a schematic diagram of the working process of a redundant starting motor system for high-pressure liquid resistance soft starter and solid-state soft starter according to this utility model.

[0022] In the diagram, 1. First incoming line circuit breaker; 2. Second incoming line circuit breaker; 3. Motor No. 1; 4. Motor No. 2; 5. First liquid circuit breaker; 6. Second liquid circuit breaker; 7. First switching circuit breaker; 8. Third switching circuit breaker; 9. Fourth liquid circuit breaker; 10. Third liquid circuit breaker; 11. High-voltage solid-state soft starter cabinet. Detailed Implementation

[0023] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings. These embodiments do not constitute a limitation on this utility model. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this application.

[0024] A redundant starter motor system combining high-pressure liquid resistance soft starter and solid-state soft starter, such as Figure 1 As shown, it includes a switching cabinet and several incoming line cabinets. The incoming line cabinets are respectively connected to the corresponding motors. The switching cabinet includes several switching circuit breakers. The other end of the motor is connected to the corresponding star point cabinet, liquid resistance starter cabinet and corresponding switching circuit breaker. The other end of each switching circuit breaker is connected to the high voltage solid-state soft starter cabinet 11. The motor is started through the liquid resistance starter cabinet or the high voltage solid-state soft starter cabinet 11 and runs at full voltage through the star point cabinet.

[0025] like Figure 1 As shown, in this embodiment, there are two sets of incoming line cabinets and star point cabinets with liquid resistance starting cabinets (original equipment). The incoming line cabinets include No. 1 incoming line cabinet and No. 2 incoming line cabinet. No. 1 incoming line cabinet and No. 2 incoming line cabinet are respectively connected to No. 1 motor 3 (fan motor) and No. 2 motor 4 (fan motor). The switching cabinet includes a first switching circuit breaker 7 and a third switching circuit breaker 8 and a live indicator. The other end of No. 1 motor 3 is connected to No. 1 star point cabinet, No. 1 liquid resistance starting cabinet and the first switching circuit breaker 7. The other end of No. 2 motor 4 is connected to No. 2 star point cabinet, No. 2 liquid resistance starting cabinet and the third switching circuit breaker 8. The other ends of the first switching circuit breaker 7 and the third switching circuit breaker 8 are both connected to the high-voltage solid-state soft starter cabinet 11 and the live indicator. The high-voltage solid-state soft starter cabinet 11 realizes solid-state soft start. The live indicator serves as a prompting safety device to show whether the switching cabinet has operating voltage.

[0026] like Figure 1As shown, specifically, the No. 1 incoming line cabinet includes a first incoming line circuit breaker 1, and the No. 2 incoming line cabinet includes a second incoming line circuit breaker 2, to realize the incoming line; the No. 1 liquid resistance starter cabinet includes a first liquid resistance circuit breaker 5 and a first water resistor, and the No. 2 liquid resistance starter cabinet includes a third liquid resistance circuit breaker 10 and a second water resistor, to realize liquid resistance soft start; the high-voltage solid-state soft starter cabinet 11 includes an internal thyristor valve group, to realize solid-state soft start; the No. 1 star point cabinet includes a second liquid resistance circuit breaker 6, and the No. 2 star point cabinet includes a fourth liquid resistance circuit breaker 9, to realize soft start and switch to the full-pressure operation state of the fan motor, completing the start-up process;

[0027] In other embodiments, the first switching circuit breaker 7 and the third switching circuit breaker 8 are prevented from closing simultaneously by an interlocking protection device to prevent short-circuit impact on the power grid during startup. The interlocking protection device can be an existing structure such as electrical interlocking and mechanical interlocking to prevent accidents from occurring.

[0028] Working principle:

[0029] This embodiment achieves the optimization and upgrade of equipment configuration and function, taking into account both the full utilization of the original equipment and the efficient integration of the new equipment; in terms of equipment composition, the two high-pressure water resistance soft start cabinets are retained, and they still undertake the task of controlling motor 3 (M1) and motor 4 (M2) respectively.

[0030] With its mature technology and stable performance, the water resistance soft starter cabinet adjusts the motor's starting current and torque by changing the water resistance during the startup process, ensuring a smooth motor start-up.

[0031] High-voltage solid-state soft starters greatly enhance the flexibility and functionality of the system. They have the ability to control two motors simultaneously and employ advanced power electronics technology to achieve smooth motor starting, effectively reducing the impact on the power grid during startup.

[0032] In addition, in some other embodiments, it can also be equipped with a PLC control system to further assist in the combination and switching between the excitation system, solid-state soft starter and liquid resistance cabinet, so as to achieve flexible switching and improve the reliability of motor starting.

[0033] like Figure 2 As shown, its working process includes:

[0034] (1) Preparation stage: During this process, the next step can only be carried out after the following external conditions are met: ① the oil pressure signal is normal; ② the damper zero-degree signal is normal; ③ the circuit breaker tripping signal at each point is normal; ④ the interlocking signal at each part of the system is normal; ⑤ the excitation cabinet signal is normal.

[0035] (2) Closing and Operation Stage: When the above conditions are met, if water resistance starting is required (taking starting motor 3 as an example), the following steps shall be performed:

[0036] S21, manually close the first liquid circuit breaker 5 (QF1′);

[0037] S22, press the start switch of motor 3, the first incoming circuit breaker 1 (1QF) closes, the circuit of the first liquid resistance starter cabinet is connected, the distance between the two plates in the cabinet continuously decreases, which is equivalent to the resistance value in the series circuit gradually decreasing.

[0038] S23, when the water resistance in the series circuit decreases to a certain extent, the motor speed reaches more than 95% of the synchronous speed, the excitation cabinet is energized, and the second liquid circuit breaker 6 (QF2) in the No. 1 star point cabinet is closed, and the No. 1 motor 3 runs at full voltage.

[0039] S24, the distance between the two plates inside the No. 1 liquid resistance starter cabinet automatically returns to its original state to facilitate the next start.

[0040] (3) When a high-voltage solid-state soft starter is required (taking the starting of motor 3 as an example), the following steps shall be performed:

[0041] S31. First, manually disconnect the first liquid circuit breaker 5 (QF1′) to prevent the No. 1 liquid resistance starter cabinet from being connected in parallel with the high-voltage soft starter, which would reduce the total resistance of the starting circuit and damage the motor. Only after this is done can the next step of starting work be carried out.

[0042] S32, press the start switch of motor 3, the first switching circuit breaker 7 (QF1) closes, the high voltage soft starter circuit is connected, and the motor starts to start;

[0043] S33, when the speed reaches more than 95% of the synchronous speed of the motor, the excitation cabinet is excited and the second liquid circuit breaker 6 (QF2) in the No. 1 star point cabinet is closed. The high-voltage solid soft starter is taken out of operation and reset so that it can be started again. The No. 1 motor 3 runs at full voltage and the starting process is completed.

[0044] To start motor 4, the starting process is the same as in processes (2) and (3) above.

[0045] (4) Operation results: No abnormalities were found during the trial operation. The fan was able to start and run normally multiple times, and the start-up process was stable.

[0046] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model. Those skilled in the art can make various modifications or equivalent substitutions to the present utility model within its substance and protection scope, and such modifications or equivalent substitutions should also be considered to fall within the protection scope of the present utility model's technical solution.

Claims

1. A high voltage liquid resistance soft start and solid state soft start redundant motor starting system, characterized by: It includes a switching cabinet and several incoming line cabinets. The switching cabinet includes several switching circuit breakers. The incoming line cabinets are respectively connected to the corresponding motors. The other end of the motor is connected to the corresponding star point cabinet, liquid resistance starter cabinet and corresponding switching circuit breaker. The other end of each switching circuit breaker is connected to the high voltage solid-state soft starter cabinet. The motor is started through the liquid resistance starter cabinet or the high voltage solid-state soft starter cabinet and runs at full voltage through the star point cabinet.

2. A high pressure hydraulically dampened soft start and solid state soft start redundant motor system according to claim 1, characterized in that: The incoming line cabinet includes an incoming line cabinet No. 1 and an incoming line cabinet No. 2, which are respectively connected to motor No. 1 and motor No.

2. The switching cabinet includes a first switching circuit breaker and a third switching circuit breaker. The other end of motor No. 1 is connected to the first star point cabinet, the first hydraulic resistance starter cabinet and the first switching circuit breaker, and the other end of motor No. 2 is connected to the second star point cabinet, the second hydraulic resistance starter cabinet and the third switching circuit breaker.

3. The high-pressure liquid resistance soft starter and solid-state soft starter redundant starter motor system according to claim 2, characterized in that: The No. 1 incoming line cabinet includes a first incoming line circuit breaker, and the No. 2 incoming line cabinet includes a second incoming line circuit breaker.

4. A high pressure hydrostatic soft start and solid state soft start redundant motor system as claimed in claim 2 or 3, characterized in that: The No. 1 liquid resistance starter cabinet includes a first liquid circuit breaker and a first water resistor, and the No. 2 liquid resistance starter cabinet includes a third liquid circuit breaker and a second water resistor.

5. A high pressure hydraulically dampened soft start and solid state soft start redundant motor system as set forth in claim 2, wherein: The No. 1 star point cabinet includes a second liquid circuit breaker, and the No. 2 star point cabinet includes a fourth liquid circuit breaker.

6. The high-pressure liquid resistance soft starter and solid-state soft starter redundant starter motor system according to claim 2, characterized in that: The first and third switching circuit breakers are protected by an interlocking device to prevent them from closing simultaneously.

7. A high pressure hydraulically dampened soft start and solid state soft start redundant motor system as described in claim 1, wherein: The high-voltage solid-state soft starter cabinet includes an internal thyristor valve group.

8. A high pressure hydrostatic soft start and solid state soft start redundant motor system as set forth in either claim 1 or claim 7, characterized by: The switching cabinet also includes a live display.

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