Fan feedback protection and control loop of slip frequency cabinet

Abstract

The invention relates to the technical field of in-cabinet temperature control protection, in particular to a slip frequency cabinet fan feedback protection and control loop. The central control module controls start and stop of a slip frequency cabinet cooling fan and receives a fan operation state and a fault signal; the cooling monitoring module is connected to the central control module, and a loop is disconnected as required; the auxiliary on-off module comprises double air switch groups and matched antioxidant 1NO / NC auxiliary contacts and is used for fan power supply control and state feedback. The 1NO / NC type auxiliary contact with good sealing performance and high oxidation resistance is adopted to replace an original contact, the problem of contact resistance rising caused by moisture and corrosion is remarkably solved, the feedback stability of on-off state signals of the fan is enhanced, the temperature control switch with the action temperature being 60 DEG C is introduced, fire diffusion caused by continuous operation of the fan is prevented, and the service life of the fan is prolonged. And the wiring ports and the wire numbers of the air switches F1 and F2 and the auxiliary contacts are regulated in a standardized manner, so that the maintenance path is simplified, the operation complexity of operation and maintenance is reduced, and the operation reliability and the system maintainability are improved.

Description

Technical Field

[0001] This invention relates to the field of cabinet temperature control and protection technology, and in particular to a feedback protection and control circuit for a differential locker fan. Background Technology

[0002] With the rapid development of the wind power industry, the structure of wind turbine units has been continuously optimized. However, during long-term operation, the heat dissipation and protection systems of key equipment such as the differential locker still face harsh operating environments. Models like the Suzlon S82-1500 generally use air cooling for their differential lockers, relying on the effective operation of cooling fans to ensure the normal temperature range of electrical components such as diodes and IGBTs. However, in actual operation, a series of technical deficiencies remain in the start-stop control of the differential locker's cooling fans, power protection, and fault feedback loops, seriously affecting the stability and safety of the wind turbine operation.

[0003] In current applications, the control of cooling fans relies on power switches and their associated auxiliary contacts for status feedback, with signals transmitted to the monitoring system for trip detection. However, in existing technologies, these auxiliary contacts are prone to increased contact resistance due to environmental factors such as humidity and oxidation, leading to signal distortion or loss. This results in inaccurate reception of the fan's on / off status, frequently triggering erroneous alarms from the differential lock, affecting fan operation judgment and remote control strategies. More seriously, the current system lacks fire-linked protection logic. When a fire occurs inside the differential lock, the fan may continue to run due to delays or interruptions in the upper-level control logic, exacerbating the spread of the fire and failing to meet the fire safety requirements for electrical cabinets.

[0004] Therefore, there is a need for a differential locker fan feedback protection and control loop that can significantly improve the stability of fan control switches and auxiliary contacts, reduce false alarm rates and operational failures caused by contact oxidation, construct a linkage power-off protection mechanism in the event of a fire inside the differential locker, and significantly improve the safety and reliability of fan operation to meet the needs of the current environment. Summary of the Invention

[0005] The purpose of this section is to outline some aspects of the embodiments of the present invention and to briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section, as well as in the specification abstract and the title of the invention, to avoid obscuring the purpose of this section, the specification abstract, and the title of the invention. Such simplifications or omissions shall not be used to limit the scope of the invention.

[0006] Given that in the aforementioned existing technologies, the auxiliary contacts are prone to increased contact resistance due to environmental factors such as humidity and oxidation, which can lead to signal distortion or loss, making it impossible to accurately receive the fan's on / off status and frequently triggering incorrect alarms from the differential lock. Furthermore, the system is not configured with fire linkage protection logic, so in the event of a fire, the fan may continue to operate due to delays or interruptions in the upper-level control logic.

[0007] Therefore, the technical problem to be solved by the present invention is to design a slip-ring cabinet fan feedback protection and control loop that can significantly improve the stability of the fan control switch and auxiliary contacts, reduce the false alarm rate and operation failure caused by contact oxidation, construct a linkage power-off protection mechanism in the case of fire inside the slip-ring cabinet, and significantly improve the safety and reliability of the fan operation to meet the needs of the current environment.

[0008] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a differential lock fan feedback protection and control circuit, comprising,

[0009] The central control module controls the start and stop of the cooling fan of the differential lock cabinet and receives the fan's operating status and fault signals.

[0010] The cooling monitoring module is connected to the central control module to provide backup protection against high-temperature disasters and disconnect the circuit as needed;

[0011] The auxiliary switching module includes a dual air switch group with anti-oxidation 1NO / NC auxiliary contacts for fan power supply control and status feedback.

[0012] As an improvement of the present invention,

[0013] The cooling monitoring module is connected in series with a secondary temperature control unit, and the temperature control threshold of the secondary temperature control unit is 60℃.

[0014] The central control module is equipped with a cooling monitoring interface, which is a multi-channel communication interface.

[0015] One end of the secondary temperature control unit is connected to the cooling monitoring docking port, and the other end is electrically connected to the corresponding circuit of the fan contact unit.

[0016] As an improvement of the present invention,

[0017] The central control module is electrically connected to the 240V voltage input port to provide power for the circuit.

[0018] A 240V voltage input port is connected to an auxiliary switching module. A circuit switch is fixedly installed inside the auxiliary switching module. When the circuit switch is closed, a high-voltage power supply circuit is formed.

[0019] One end of the circuit breaker is connected to a 240V voltage input port, and the other end is connected to a cooling monitoring docking port to realize the monitoring and control of the central control module.

[0020] As an improvement of the present invention,

[0021] The central control module is equipped with a Crowb protection processing unit, which can generate protection action signals under fault conditions;

[0022] The output of the Crowb protection processing unit is connected to the Crowb working unit to output trip protection commands.

[0023] As an improvement of the present invention,

[0024] The Crowb working unit includes a 230V working power supply, providing independent power to the Crowb working unit;

[0025] The 230V working power supply is connected to the air switch group F1 in the auxiliary switching module. Air switch F1 provides front-end protection for the Crowb working unit.

[0026] The other end of the air switch group F1 is connected to the voltage input terminal X4.

[0027] As an improvement of the present invention,

[0028] The air switch group F1 in the auxiliary switching module is connected in parallel with the air switch group F2 to form a dual-circuit protection branch structure;

[0029] One end of the air switch group F2 is connected to the fan control assembly, and the fan control assembly is electrically connected to the fan contact unit;

[0030] The fan control assembly receives start / stop signals from the central control unit and cooling monitoring unit, and the other end of the air switch group F2 is connected to the voltage input terminal X5.

[0031] As an improvement of the present invention,

[0032] The fan control assembly is equipped with a sensor-activated on / off switch group to achieve responsive control of the fan's power supply status;

[0033] The inductive on / off switch group is electrically connected to the fan contact unit, and the other end is connected to the fan output terminal;

[0034] The control signal for the switching fan contact unit is used to control the on / off state of the fan operating current.

[0035] As an improvement of the present invention,

[0036] The central control module is equipped with an IGBT control unit to generate control pulse signals for the fan drive power transistors;

[0037] One end of the IGBT control unit is connected to the signal output interface of the central control unit, and the other end is electrically connected to the IGBT drive assembly for real-time driving and status management.

[0038] The IGBT drive assembly adjusts the output power of the fan load side based on the output signal of the IGBT control unit.

[0039] As an improvement of the present invention,

[0040] The central control module is equipped with a CT circuit drive power supply group;

[0041] The CT circuit drive power supply group provides a stable voltage for the current transformers and sampling circuits in the cabinet system.

[0042] The beneficial effects of this invention are as follows: replacing the original contacts with 1NO / NC type auxiliary contacts that have good sealing performance and strong oxidation resistance significantly reduces the problem of increased contact resistance caused by moisture and corrosion, enhances the feedback stability of the fan on / off status signal, introduces a temperature control switch with an operating temperature of 60°C, and can forcibly disconnect the fan contactor power supply once the temperature exceeds the set threshold to prevent the fan from continuing to run and causing the fire to spread, and standardizes the wiring ports and wire numbers of F1, F2 air switches and auxiliary contacts, simplifies the maintenance path, reduces the complexity of operation and maintenance, and improves the reliability and maintainability of the system. Attached Figure Description

[0043] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein:

[0044] Figure 1 This is a schematic diagram of the overall architecture of the differential lock fan feedback protection and control circuit in this invention.

[0045] Figure 2 This is a partial operational block diagram of the differential lock fan feedback protection and control circuit in this invention.

[0046] Figure 3 This is a diagram of the auxiliary circuit structure for the feedback protection and control loop of the differential lock fan in this invention. Detailed Implementation

[0047] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0048] Example 1

[0049] Reference Figure 1 This embodiment provides a feedback protection and control circuit for the fan of a differential lock cabinet.

[0050] A feedback protection and control loop for a differential locker fan includes a central control module 1, a cooling monitoring module 2, and an auxiliary on / off module 3. The modules are electrically connected to form a linkage control system, which is used to realize the safe operation and status monitoring of the cooling fan inside the differential locker of the wind turbine.

[0051] The central control module 1 is used to control the start and stop of the cooling fan in the differential lock cabinet. It is internally equipped with corresponding control signal output ports and status acquisition input ports. When the fan is running, the central control module 1 can issue start or stop commands through its internal logic or a corresponding external PLC control unit. Feedback signals from the auxiliary contacts in the auxiliary on / off module 3, as well as temperature status signals from the cooling monitoring module 2, are sent to the central control module 1. Through these signals, the central control module 1 can determine whether the fan is operating normally and whether there are faults such as overheating or tripping.

[0052] The cooling monitoring module 2 is electrically connected to the central control module 1 and contains a temperature control switch unit for backup protection in case of high-temperature faults. In this solution, a mechanical bimetallic temperature controller, model NTK1-111G, is selected as the temperature control switch, with an operating temperature set at 60℃.

[0053] The output of the temperature control switch is connected in series in the contactor control circuit of the fan control circuit. When the internal temperature of the cabinet exceeds the set threshold, the temperature control switch will disconnect, thereby cutting off the control power of the contactor coil and forcing the fan to stop running. This prevents the fan from continuing to run in the event of a fire or severe overheating, which could cause the fire to spread or cause secondary failures.

[0054] The auxiliary switching module 3 includes two sets of air switches, F1 and F2, which control different branches respectively. F1 and F2 are two-pole (2P) air switches, selected as IC65N6KA2PD4A (F1) and IC65N6KA2PD10A (F2) respectively, forming a reasonable differential protection between them. This module is also equipped with Schneider A9A26904 auxiliary contacts, with a 1NO / NC contact configuration, which has strong oxidation and moisture resistance.

[0055] The corresponding auxiliary contacts are connected to the central control module 1 through standard wiring terminals to provide real-time feedback of the air switch status signal, thereby enabling the monitoring of whether the fan is in "working state" or "tripped state" and improving the closed-loop control capability of the entire system.

[0056] In this embodiment, to ensure the stability of the auxiliary contact feedback signal, the system also optimizes and adjusts the wiring of the original auxiliary contact circuit. For example, the auxiliary contact signal lines of F1 are adjusted from F1:33 and F1:34 to F1:11 and F1:14 to ensure that the signal is connected to the designated feedback channel of the central control module. Similarly, the signals of the F2 contact are adjusted from F2:33 and F2:34 to F2:11 and F2:14, making the overall layout clearer and facilitating inspection and maintenance.

[0057] Example 2

[0058] Reference Figures 1-3 This embodiment is based on the previous embodiment, and differs from the previous embodiment in that:

[0059] The cooling monitoring module 2 is connected in series with a secondary temperature control unit 21. The secondary temperature control unit 21 adopts a mechanical bimetallic strip structure, model NTK1-111G, with a temperature control threshold set at 60℃, and has high operational reliability. When the internal temperature of the differential lock cabinet continues to rise above the set threshold due to cooling failure, system overload, or local electrical breakdown, the secondary temperature control unit 21 will automatically disconnect the fan control branch, forming a local emergency protection channel independent of the upper control logic.

[0060] The central control module 1 is equipped with a cooling monitoring docking port 11. This port adopts a multi-channel isolated communication interface, which can simultaneously transmit status signals, contactor control signals and temperature disconnection signals. One end of the secondary temperature control unit 21 is connected to the cooling monitoring docking port 11, and the other end is connected in series with the circuit of the fan contact unit 23 to realize automatic disconnection of fan operation when the temperature is too high.

[0061] The central control module 1 is electrically connected to the 240V voltage input port 4. The 240V voltage input port 4 serves as the main power source for the fan control and auxiliary power execution layer in the differential lock cabinet, and its power supply is controlled by the line switch in the auxiliary switching module 3. The voltage input port 4 is connected to the auxiliary switching module 3 via a wire. The auxiliary switching module 3 contains a line switch 31, which is an AC air circuit breaker with overcurrent and short-circuit protection characteristics. One end of the line switch 31 is connected to the 240V input terminal, and the other end is connected to terminal 8 of the cooling monitoring docking port 11, forming a controllable high-voltage power supply path to achieve power linkage and status monitoring between the cooling control module and the central control module.

[0062] To achieve protection and control of critical power circuits, the central control module 1 is also equipped with a Crowb protection processing unit 12. The Crowb protection processing unit 12 is used to output a trip protection signal when serious faults such as overcurrent, abnormal grounding, and temperature runaway are detected in the differential lock. This signal is transmitted to the Crowb working unit 5 through the control line, triggering the execution unit to trip or cut off the power to prevent the fault from spreading.

[0063] The Crowb operating unit 5 internally includes a 230V operating power supply group 51, which provides independent power to the Crowb operating logic to prevent protection failure due to main control power supply abnormalities. This operating power supply group is connected to the air switch F1 in the auxiliary switching module 3. F1 acts as a pre-stage protection device, with one end connected to the voltage input port X4, creating a protected operating path for the Crowb module. The disconnection action of F1 can be controlled by the Crowb protection unit in conjunction with the circuit, or it can trip independently in the event of a power failure or load short circuit.

[0064] To achieve electrical isolation between the fan main circuit and the Crowb protection processing unit 12, the air switch F1 in the auxiliary switching module 3 and another set of air switches F2 are arranged in parallel to form a dual-circuit protection branch structure. Among them, F2 is used to control the fan main circuit. One end of F2 is connected to the fan control assembly 6, and the other end of F2 is connected to the independent voltage input terminal X5 to prevent the power supply of the Crowb circuit from being affected when the fan load circuit is abnormal.

[0065] The fan control assembly 6 is electrically connected to the fan contact unit 23 to receive start / stop commands from the central control module 1 and the cooling monitoring module 2, thereby realizing the start / stop logic control of the cooling fan. The control assembly internally includes a sensor-activated on / off switch group 61, one end of which is connected to the output control terminal of the fan contact unit 23, and the other end is connected to the actual fan output terminal. This group converts the control signal output by the contactor into actual power supply status changes, thereby controlling the on / off state of the fan operating current.

[0066] To achieve precise power control of the main circuit of the wind turbine, the central control module 1 is equipped with an IGBT control unit 13, which is used to generate PWM control signals or logic trigger pulses to control the on and off states of the IGBT power devices in the slip-ring cabinet.

[0067] One end of the IGBT control unit 13 is connected to the signal output port of the central control module 1, and the other end is connected to the IGBT drive assembly 7. The IGBT drive assembly receives control signals to adjust the output power of the fan and set response strategies, such as load flexible start-stop and temperature-limited power operation.

[0068] The central control module 1 also integrates a CT circuit drive power supply group 14, which provides independent and stable low-voltage DC power to the current transformers and their associated sampling circuits in various parts of the differential lock system. The power supply group has anti-interference and filtering functions, which can improve the accuracy of current sampling and noise immunity, and provide basic data support for fault detection, current judgment and calculation modules.

[0069] Through the integration of the above multiple modules, this embodiment realizes a complete closed-loop control of functions such as fan control, power protection, temperature control linkage, Crowb tripping, load regulation and current sampling. It has high safety, reliability and engineering adaptability, and is suitable for promotion and application in the Suzlon S82-1500 fan slip differential switch system, with good industrialization prospects.

[0070] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A feedback protection and control circuit for a differential lock fan, characterized in that: include, The central control module (1) controls the start and stop of the cooling fan of the sliding cabinet and receives the fan's operating status and fault signals; The cooling monitoring module (2) is connected to the central control module (1) to provide backup protection against high temperature disasters and disconnect the circuit as needed; The auxiliary switching module (3) includes a dual air switch group with anti-oxidation 1NO / NC auxiliary contacts for fan power supply control and status feedback.

2. The slip-ring cabinet fan feedback protection and control circuit according to claim 1, characterized in that: The cooling monitoring module (2) is connected in series with a secondary temperature control unit (21), and the temperature control threshold of the secondary temperature control unit (21) is 60℃; The central control module (1) is equipped with a cooling monitoring docking port (11), which is a multi-channel communication interface; One end of the secondary temperature control unit (21) is connected to the cooling monitoring docking port (11), and the other end is electrically connected to the corresponding circuit of the fan contact unit (23).

3. The differential lock fan feedback protection and control circuit according to claim 1, characterized in that: The central control module (1) is electrically connected to the 240V voltage input port (4) to provide power for the circuit. The 240V voltage input port (4) is connected to the auxiliary switching module (3). The auxiliary switching module (3) is fixedly equipped with a line switch (31). When the line switch (31) is closed, a high-voltage power supply circuit is formed. One end of the line switch (31) is connected to the 240V voltage input port (4), and the other end is connected to the cooling monitoring docking port (11) to realize the monitoring and control of the central control module (1).

4. The slip-ring cabinet fan feedback protection and control circuit according to claim 1, characterized in that: The central control module (1) is equipped with a Crowb protection processing unit (12), which can generate protection action signals under fault conditions; The output terminal of the Crowb protection processing unit (12) is connected to the Crowb working unit (5) to output a trip protection command.

5. The differential lock fan feedback protection and control circuit according to any one of claims 1 to 4, characterized in that: The Crowb working unit (5) includes a 230V working power supply (51) to provide independent power to the Crowb working unit (5); The 230V working power supply group (51) is connected to the air switch group F1 in the auxiliary switching module (3). The air switch F1 provides front-end protection for the Crowb working unit (5). The other end of the air switch group F1 is connected to the voltage input terminal X4.

6. The slip-ring cabinet fan feedback protection and control circuit according to claim 5, characterized in that: The air switch group F1 in the auxiliary switching module (3) is connected in parallel with the air switch group F2 to form a dual-circuit protection branch structure; One end of the air switch group F2 is connected to the fan control assembly (6), and the fan control assembly (6) is electrically connected to the fan contact unit (23); The fan control assembly (6) receives start / stop signals from the central control unit (1) and the cooling monitoring unit (2), and the other end of the air switch group F2 is connected to the voltage input terminal X5.

7. The slip-ring cabinet fan feedback protection and control circuit according to claim 6, characterized in that: The fan control assembly (6) is equipped with a sensor on / off switch group (61) to realize response control of the fan power supply status; The inductive on / off switch group (61) is electrically connected to the fan contact unit (23), and the other end is connected to the fan output terminal; The control signal of the switching fan contact unit (23) is used to control the on / off state of the fan operating current.

8. The differential lock fan feedback protection and control circuit according to claim 6 or 7, characterized in that: The central control module (1) is equipped with an IGBT control unit (13) to generate control pulse signals for the fan drive power transistor; One end of the IGBT control unit (13) is connected to the signal output interface of the central control unit (1), and the other end is electrically connected to the IGBT drive assembly (7) for real-time driving and status management. The IGBT drive assembly (7) adjusts the output power of the fan load side based on the output signal of the IGBT control unit (13).

9. The slip-ring cabinet fan feedback protection and control circuit according to claim 8, characterized in that: The central control module (1) sets up the CT circuit drive power supply group (14); The CT circuit drive power supply group (14) provides a stable voltage for the current transformer and sampling circuit in the cabinet system.

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