A three-screw pump anti-reverse rotation protection device and method based on electrical phase sequence

Abstract

The application provides a three-phase sequence-based anti-reverse protection device and method for a three-screw pump, and relates to the technical field of anti-reverse protection for three-screw pumps.The device comprises an anti-reverse device module, which is fixedly installed above the tail of a three-phase motor.The anti-reverse device module comprises a shell and a circuit board arranged inside the shell.A signal acquisition module, a control feedback module, a current conversion unit, a phase sequence judgment circuit, a bottom-layer execution module, a power input unit and an SSR relay are arranged on the circuit board.The power input unit is connected with the current conversion unit and the SSR relay.The current conversion unit is electrically connected with the control feedback module.The control feedback module is electrically connected with the signal acquisition module.The control feedback module is connected with the SSR relay through the bottom-layer execution module, and the SSR relay is electrically connected with the three-phase motor.The device has a significantly reduced equipment loss, a significantly improved debugging efficiency, enhanced protection reliability and convenient intelligent management and operation and maintenance.

Description

Technical Field

[0001] This invention relates to the field of anti-reverse rotation protection technology for three-screw pumps, and more specifically, to an anti-reverse rotation protection device and method for three-screw pumps based on electrical phase sequence. Background Technology

[0002] Three-screw pumps, as highly efficient positive displacement pumps, are widely used in industrial fields due to their compact structure, stable operation, low noise, and long service life, playing a particularly important role in hydraulic lubrication systems and machine tool cooling and flushing systems. Three-screw pumps are rotating structures with a defined rotation direction. They must operate according to the designed rotation direction; otherwise, the pump inlet and outlet will be interchanged, the flow path will change, and normal fluid delivery will be impossible. More seriously, internal components such as the locking nut are designed to align with the rotation direction; reverse rotation will cause these components to loosen and damage the pump. Furthermore, reverse rotation will disable the thrust balancing device, accelerating equipment damage. Common causes of three-screw pump reverse rotation include: reversed phase sequence of the drive motor, especially the electric motor, leading to incorrect rotation direction; lack of a check valve on the output pipeline, causing backflow of medium after shutdown, driving the pump in reverse; and when multiple pumps are operating in parallel, one pump's operation may force the medium into the outlet of another pump, causing it to reverse. During the equipment commissioning phase, the power input phase sequence is arbitrary, making it impossible to control the correct direction of the three-screw pump in advance. Especially in submerged installation environments, the direction of rotation is difficult to discern with the naked eye, which can easily lead to reverse rotation accidents caused by incorrect wiring.

[0003] Currently, existing anti-reverse technology mainly employs mechanical one-way bearings, ratchet and pawl structures. Taking the ratchet and pawl anti-reverse device widely used in screw pump drives as an example, the pawl is mounted on a fixed spindle and rotates freely. A spring ensures normal engagement between the pawl and ratchet. During normal operation, centrifugal force causes the pawl to overcome the spring force and separate from the ratchet. During reverse operation, the pawl engages under the action of the spring force to prevent reversal. However, these traditional methods have the following objective drawbacks: First, the mechanical structure is prone to failure. The ratchet and pawl device is prone to failure under transient high-pressure impact conditions. When the initial reverse velocity is zero, the pawl engages with the ratchet, generating an impact, and the reversal cannot be automatically released. The mechanical structure has gaps, which can easily lead to impact damage to the screw meshing surface. Second, there is mechanical wear. One-way bearings, pawls, and other mechanical anti-reverse structures are wear-prone parts. After long-term operation, wear leads to protection failure, increasing the cost of parts replacement and downtime for maintenance. Third, there is a lack of intelligent monitoring. Existing mechanical anti-reverse structures cannot monitor the power phase sequence status in real time, and the protection is limited to unidirectional braking at the mechanical level. They lack fault diagnosis and information reporting functions, making it difficult to meet the requirements of industrial automation for equipment intelligence. Fourth, the commissioning efficiency is low. During the initial installation and commissioning of the equipment, the direction must be confirmed by inching. If an incorrect direction is found, the input power line must be replaced, requiring repeated operations and consuming a lot of time. Summary of the Invention

[0004] This invention aims to solve the technical problems of easy wear, slow response, inability to intelligently monitor, and low debugging efficiency in existing three-screw pump anti-reverse technology, such as mechanical one-way bearings and ratchet and pawl structures.

[0005] To solve the above problems, the present invention provides an anti-reverse rotation protection device for a three-screw pump based on electrical phase sequence, including an anti-reverse rotation device module. The anti-reverse rotation device module is fixedly installed above the tail of the three-phase motor, and the output end of the three-phase motor is rigidly connected to the front-end three-screw pump through a coupling. The anti-reverse device module includes a housing and a circuit board disposed inside the housing; the circuit board is provided with a signal acquisition module, a control feedback module, a current conversion unit, a phase sequence judgment circuit, a low-level execution module, a power input unit, and an SSR relay; The outer casing is equipped with multiple waterproof connectors. External AC 380V power is connected to the power input unit through the waterproof connectors. The output of the power input unit is connected to both the current conversion unit and the SSR relay. The output of the current conversion unit is electrically connected to the power supply terminal of the control feedback module. The signal input terminal of the control feedback module is electrically connected to the signal acquisition module. The control feedback module contains a phase sequence judgment circuit. The output of the control feedback module is connected to the control terminal of the SSR relay through the underlying execution module. The SSR relay is electrically connected to the three-phase motor.

[0006] The present invention provides a reverse rotation protection device and method for a three-screw pump based on electrical phase sequence, which, compared with the prior art, has the following beneficial effects, but is not limited to: The invention significantly reduces equipment wear. Compared to traditional mechanical one-way bearings, ratchet pawls, and other easily worn anti-reverse structures, the invention adopts a purely electrical contactless control scheme. There is no impact from screw meshing caused by mechanical clearance, which completely eliminates faults such as reverse pump jamming and lubrication failure. This greatly extends the service life of the screw pump and motor, and reduces the cost of parts replacement and downtime maintenance.

[0007] The debugging efficiency of this invention is significantly improved. The phase sequence can be automatically checked as soon as the device is powered on. Compared with the traditional mechanical structure, which requires repeated switching of power lines to confirm the direction of rotation, this invention greatly improves the debugging efficiency and shortens the debugging time.

[0008] The present invention enhances the reliability of protection. Traditional mechanical anti-reverse structures are prone to failure under transient high-voltage impacts, while the present invention uses SSR relays to achieve contactless electrical control, eliminates mechanical wear, has strong impact resistance, and has continuous online monitoring function, achieving protection at all times during startup and operation.

[0009] The intelligent management of this invention facilitates operation and maintenance. This invention has functions such as fault signal uploading and alarm, human-machine interaction display, and operation data storage, which facilitates the monitoring of automated production lines in factories, can quickly locate wiring faults, and lowers the technical threshold for operation and maintenance.

[0010] Furthermore, the control feedback module is electrically connected to the human-machine interaction module, which is located on the surface of the housing 51 of the anti-reverse device module 5 or connected to the control cabinet panel via a signal line.

[0011] Furthermore, a bell-shaped cover is fitted over the coupling.

[0012] Furthermore, the three-phase motor is equipped with a base.

[0013] Furthermore, the current conversion unit incorporates overcurrent protection components and an AC-DC conversion circuit.

[0014] Furthermore, the SSR relay is a three-phase solid-state relay module, which has a built-in heat sink and a zero-crossing trigger circuit.

[0015] Furthermore, the phase sequence determination circuit includes a phase sequence comparator composed of an operational amplifier.

[0016] A method for preventing reverse rotation of a three-screw pump based on electrical phase sequence includes the following steps: S1: Power-on self-test procedure. When the device is powered on for the first time, the current conversion unit converts AC380V AC power into DC control voltage to power the control feedback module. The control feedback module initializes and performs a self-test upon power-on. S2: Phase sequence identification and determination steps. The phase sequence determination circuit in the control feedback module collects the phase sequence signal of the three-phase power supply of the three-phase motor in real time through the signal acquisition module, and determines whether the current power supply phase sequence is positive or negative. S3: Direction locking and execution steps. When the phase sequence is correct, the control feedback module outputs a valid direction locking signal, the SSR relay is turned on, and the motor rotates in the forward direction to drive the screw pump. When the phase sequence is incorrect, the control feedback module immediately cancels the direction locking signal and outputs an interlock feedback signal. The SSR relay instantly disconnects the motor main circuit to prevent reverse rotation and sends a phase sequence fault alarm signal at the same time. S4: Operation monitoring steps. During the entire normal operation of the equipment, the control feedback module continuously monitors the power phase sequence status in real time. When an abnormal change in phase sequence is detected, the operation of the phase sequence error condition in S3 is immediately executed.

[0017] Furthermore, the method for determining whether the current power supply phase sequence is positive or negative in step S2 is as follows: the voltage phase difference between phases AB and BC of the three-phase power supply of the three-phase motor is detected respectively. When both detection results are high, it is determined to be a positive phase sequence; otherwise, it is determined to be a negative phase sequence.

[0018] Furthermore, in step S3, the phase sequence fault alarm signal displays the fault type and retains the fault record through the human-machine interaction module. Attached Figure Description

[0019] Figure 1 This is a system block diagram of an anti-reverse rotation protection device for a three-screw pump based on electrical phase sequence, according to an embodiment of the present invention. Figure 2 This is a schematic diagram of the anti-reverse rotation protection device for a three-screw pump based on electrical phase sequence according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the installation of the anti-reverse device module according to an embodiment of the present invention; Figure 4 for Figure 3 Side view.

[0020] Explanation of reference numerals in the attached figures: 1. Three-screw pump; 2. Coupling; 3. Three-phase motor; 4. Waterproof connector; 5. Anti-reverse device module; 51. Housing; 52. Circuit board. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this application clearer, specific embodiments of this application are described clearly and completely below with reference to the accompanying drawings. It should be understood that the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments described in this application without creative effort will fall within the scope of protection of this application.

[0022] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the specification of this application is for the purpose of describing specific embodiments only and is not intended to limit this application; the terms "comprising," "including," "having," "containing," "comprise," etc., in the specification, claims, and accompanying drawings of this application are open-ended terms, indicating that a method comprises one or more steps, or an apparatus comprises one or more elements, but do not exclude the inclusion of other steps or elements. The terms "first," "second," etc., in the specification, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or primary / secondary relationship. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0023] In the description of this application, it should be understood that the terms "upper", "lower", "left", "right", "front", "rear", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0024] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0025] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0026] See Figures 1-4 An embodiment of the present invention provides an anti-reverse rotation protection device for a three-screw pump based on electrical phase sequence, comprising an anti-reverse rotation device module 5, wherein the anti-reverse rotation device module 5 is fixedly installed above the tail of a three-phase motor 3, and the output end of the three-phase motor 3 is rigidly connected to the front-end three-screw pump 1 via a coupling 2. The anti-reverse device module 5 includes a housing 51 and a circuit board 52 disposed inside the housing 51; the circuit board 52 is provided with a signal acquisition module, a control feedback module, a current conversion unit, a phase sequence judgment circuit, a low-level execution module, a power input unit, and an SSR relay. The outer casing 51 is equipped with multiple sets of waterproof connectors 4. External AC 380V AC power is connected to the power input unit through the waterproof connectors 4. The output terminal of the power input unit is simultaneously connected to the current conversion unit and the SSR relay. The output terminal of the current conversion unit is electrically connected to the power supply terminal of the control feedback module. The signal input terminal of the control feedback module is electrically connected to the signal acquisition module. The control feedback module is equipped with a phase sequence judgment circuit. The output terminal of the control feedback module is connected to the control terminal of the SSR relay through the underlying execution module. The SSR relay is electrically connected to the three-phase motor 3.

[0027] In this invention, an external AC380V AC power supply is connected to the power input unit through a waterproof connector 4 to ensure electrical safety in humid or submersible installation environments.

[0028] The output of the power input unit is connected to both the current conversion unit and the SSR relay. External industrial three-phase 380V power is connected via waterproof connector 4 and then split into two paths: one is the main power circuit, directly connected to the SSR relay, and then connected to the three-phase motor 3; the other path connects to the current conversion unit. This current conversion unit has built-in overcurrent protection components and an AC-DC conversion circuit, which steps down, rectifies, and regulates the AC 380V AC power to output a 5~12V DC low voltage, providing control power to the control feedback module. The output of the current conversion unit is electrically connected to the power supply terminal of the control feedback module.

[0029] The signal acquisition module acquires the three-phase power supply phase sequence signal in real time and outputs two signals: one is a direction locking signal fed back to the SSR relay; the other is an interlock feedback signal forming a closed-loop logic, which can accurately distinguish between positive and negative phase sequence power supply states. The output of the control feedback module is connected to the control terminal of the SSR relay through the underlying execution module, and the output of the SSR relay is electrically connected to the three-phase motor.

[0030] The invention significantly reduces equipment wear. Compared to traditional mechanical one-way bearings, ratchet pawls, and other easily worn anti-reverse structures, the invention adopts a purely electrical contactless control scheme. There is no impact from screw meshing caused by mechanical clearance, which completely eliminates faults such as reverse pump jamming and lubrication failure. This greatly extends the service life of the screw pump and motor, and reduces the cost of parts replacement and downtime maintenance.

[0031] The debugging efficiency of this invention is significantly improved. The phase sequence can be automatically checked as soon as the device is powered on. Compared with the traditional mechanical structure, which requires repeated switching of power lines to confirm the direction of rotation, this invention greatly improves the debugging efficiency and shortens the debugging time.

[0032] The present invention enhances the reliability of protection. Traditional mechanical anti-reverse structures are prone to failure under transient high-voltage impacts, while the present invention uses SSR relays to achieve contactless electrical control, eliminates mechanical wear, has strong impact resistance, and has continuous online monitoring function, achieving protection at all times during startup and operation.

[0033] The intelligent management of this invention facilitates operation and maintenance. This invention has functions such as fault signal uploading and alarm, human-machine interaction display, and operation data storage, which facilitates the monitoring of automated production lines in factories, can quickly locate wiring faults, and lowers the technical threshold for operation and maintenance.

[0034] Furthermore, the control feedback module is electrically connected to the human-machine interaction module, which is located on the surface of the housing 51 of the anti-reverse device module 5 or connected to the control cabinet panel via a signal line.

[0035] The human-machine interface module can be a touch screen or an LCD screen with buttons, used for parameter setting, data acquisition and display, phase sequence abnormality display, fault alarm display, data export, and manual system start and stop.

[0036] Furthermore, a bell-shaped cover is fitted over the coupling 2.

[0037] The bell jar serves as a safety protection and reinforcement for the connection, thereby increasing safety.

[0038] Furthermore, the three-phase motor 3 is provided with a base.

[0039] The base is used to fix the device to the mounting foundation, ensuring the normal and safe operation of the device.

[0040] Furthermore, the current conversion unit incorporates overcurrent protection components and an AC-DC conversion circuit.

[0041] The AC-DC conversion circuit converts the hazardous 380V high-voltage AC power used in industry into a safe 5-12V low-voltage DC power required by the control circuit. This allows the entire anti-reverse module to operate with only a three-phase power line connection, eliminating the need for an additional 220V or 24V control power line. This not only simplifies on-site wiring but also avoids interference and potential points of failure caused by introducing an external control power supply, achieving "plug and play" convenience.

[0042] Overcurrent protection components such as fuses, resettable fuses, or overcurrent detection chips constantly monitor the current flowing into the conversion circuit. If a short circuit or abnormal overload occurs in the downstream control feedback module, sensors, or other components, this protection element will immediately cut off or limit the current. This effectively prevents excessive current from burning out delicate circuit board chips, greatly improving the reliability and survivability of the entire anti-reverse module in harsh industrial environments.

[0043] Furthermore, the SSR relay is a three-phase solid-state relay module, which has a built-in heat sink and a zero-crossing trigger circuit.

[0044] The built-in heat sink can quickly conduct heat away. This allows the SSR to operate stably under high current conditions of tens of amperes, without overheating causing internal thyristor breakdown or premature aging, greatly improving the device's field adaptability and service life.

[0045] The zero-crossing trigger circuit waits for the sinusoidal AC voltage to naturally cross the "zero point" before conducting. This eliminates the large current surges and voltage spikes during motor startup, preventing interference with the power grid, making it particularly suitable for precision machining equipment with high power quality requirements. It causes no damage to itself or the equipment: because there are no sudden voltage and current surges, the risk of the SSR itself being damaged is greatly reduced, as is the probability of damage to the motor winding insulation due to transient high voltage. It also minimizes electromagnetic interference: zero-crossing triggering avoids high-order harmonics, which is beneficial for the stable operation of signal acquisition modules such as phase sequence detection.

[0046] Furthermore, the phase sequence determination circuit includes a phase sequence comparator composed of an operational amplifier.

[0047] The signal transmission delay of operational amplifiers is typically on the order of microseconds, far faster than the sampling, A / D conversion, and software logic judgment processes required by microcontrollers. When used in conjunction with SSR relays, it can minimize the time window for the motor to receive incorrect phase sequence data, reducing the risk of impact on the screw meshing surface. Operational amplifier comparators are purely analog hardware circuits without software programs, eliminating the risk of program crashes, freezes, or resets caused by power fluctuations or strong electromagnetic interference inherent in microcontrollers.

[0048] A method for preventing reverse rotation of a three-screw pump based on electrical phase sequence includes the following steps: S1: Power-on self-test procedure. When the device is powered on for the first time, the current conversion unit converts AC380V AC power into DC control voltage to power the control feedback module. The control feedback module initializes and performs a self-test upon power-on. Upon initial power-on, the three-phase power supply is fed into the anti-reverse device module 5 via waterproof connector 4. The current conversion unit converts the AC380V AC power into a 5~12V DC control voltage to power the control feedback module. The control feedback module initializes upon power-on, performing self-tests on the signal acquisition module, phase sequence judgment circuit, underlying execution module, and human-machine interaction module.

[0049] S2: Phase sequence identification and determination steps. The phase sequence determination circuit in the control feedback module collects the phase sequence signal of the three-phase power supply of the three-phase motor 3 in real time through the signal acquisition module, and determines whether the current power supply phase sequence is positive or negative. The phase sequence judgment circuit within the control feedback module acquires the phase sequence signal of the three-phase power supply in real time through the signal acquisition module, determining whether the current power supply phase sequence is positive or negative. The phase sequence judgment circuit is implemented based on a phase sequence comparator constructed from operational amplifiers. It extracts the phase information after stepping down the three-phase voltage using resistive-capacitive components. When the phase sequence is correct, it outputs a high-level drive signal; when the phase sequence is incorrect, it outputs a low-level signal.

[0050] S3: Direction locking and execution steps. When the phase sequence is correct, the control feedback module outputs a valid direction locking signal, the SSR relay is turned on, and the motor rotates in the forward direction to drive the screw pump. When the phase sequence is incorrect, the control feedback module immediately cancels the direction locking signal and outputs an interlock feedback signal. The SSR relay instantly disconnects the motor main circuit to prevent reverse rotation and sends a phase sequence fault alarm signal at the same time. When the phase sequence is correct, the control feedback module outputs a valid direction locking signal, which is transmitted to the control terminal of the SSR relay via the underlying execution module. The main contacts of the SSR relay are turned on, and the three-phase power supply is delivered to the three-phase motor 3. The motor rotates in the forward direction and drives the three-screw pump 1 to rotate in the forward direction to transport the medium via the coupling 2.

[0051] When the phase sequence is incorrect, the control feedback module immediately cancels the direction locking signal and outputs an interlock feedback signal. The SSR relay momentarily disconnects the motor main circuit, preventing the three-phase motor from starting due to lack of power and thus preventing reverse rotation. Simultaneously, the control feedback module sends a phase sequence fault alarm signal to the human-machine interface module.

[0052] S4: Operation monitoring steps. During the entire normal operation of the equipment, the control feedback module continuously monitors the power phase sequence status in real time. When an abnormal change in phase sequence is detected, the operation of the phase sequence error condition in S3 is immediately executed.

[0053] Throughout the normal operation of the equipment, the control feedback module continuously monitors the power phase sequence status in real time through the signal acquisition module. When an abnormal change in phase sequence is detected, the operation of the phase sequence error condition in S3 is immediately executed.

[0054] Furthermore, the method for determining whether the current power supply phase sequence is positive or negative in step S2 is as follows: the voltage phase difference between phases AB and BC of the three-phase power supply of the three-phase motor 3 is detected respectively. When both detection results are high, it is determined to be a positive phase sequence; otherwise, it is determined to be a negative phase sequence.

[0055] This method accurately distinguishes between positive phase sequence ABC and negative phase sequence ACB, enhancing the anti-interference capability and reliability of phase sequence detection. If only a single path is detected, such as only AB, false triggering can easily occur during phase loss or voltage distortion. The logic condition of "both paths being high" forms a hardware "AND gate" interlock, greatly improving the accuracy and fault tolerance of the judgment, ensuring that only a true positive phase sequence can start the motor. Unlike microcontrollers, it eliminates the need for complex analog-to-digital conversion and software algorithm calculations, achieving a microsecond-level response speed. This makes phase sequence judgment almost instantaneous; if an incorrect connection is made, a protection signal can be issued instantly, working in conjunction with an SSR relay to achieve rapid power-off and maximize the protection of the screw pump.

[0056] Furthermore, in step S3, the phase sequence fault alarm signal is a fault type displayed through the human-machine interaction module and a fault record is retained.

[0057] Recording faults simultaneously with alarms means that every "phase sequence reversal" or "phase sequence abrupt change during operation" fault event will be timestamped and its type recorded. When equipment unexpectedly shuts down, maintenance personnel no longer need to "guess" whether the motor has burned out, the pump is stuck, or it's simply a wiring error. Directly retrieving the fault records allows for instant location of the root cause, significantly reducing downtime.

[0058] While the present invention has been disclosed above, its scope of protection is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, and all such changes and modifications will fall within the scope of protection of the present invention.

Claims

1. A reverse rotation protection device for a three-screw pump based on electrical phase sequence, characterized in that, It includes an anti-reverse device module (5), which is fixedly installed above the tail of the three-phase motor (3). The output end of the three-phase motor (3) is rigidly connected to the front-end three-screw pump (1) through a coupling (2). The anti-reverse device module (5) includes a housing (51) and a circuit board (52) disposed inside the housing (51); the circuit board (52) is provided with a signal acquisition module, a control feedback module, a current conversion unit, a phase sequence judgment circuit, a low-level execution module, a power input unit, and an SSR relay; The outer casing (51) is equipped with multiple sets of waterproof connectors (4). External AC380V AC power is connected to the power input unit through the waterproof connectors (4). The output end of the power input unit is connected to the current conversion unit and the SSR relay. The output end of the current conversion unit is electrically connected to the power supply end of the control feedback module. The signal input end of the control feedback module is electrically connected to the signal acquisition module. The control feedback module is equipped with a phase sequence judgment circuit. The output end of the control feedback module is connected to the control end of the SSR relay through the underlying execution module. The SSR relay is electrically connected to the three-phase motor (3).

2. The anti-reverse rotation protection device for a three-screw pump based on electrical phase sequence according to claim 1, characterized in that, The control feedback module is electrically connected to the human-machine interaction module. The human-machine interaction module is located on the surface of the outer shell (51) of the anti-reverse device module (5) or is externally connected to the control cabinet panel via a signal line.

3. The anti-reverse rotation protection device for a three-screw pump based on electrical phase sequence according to claim 1, characterized in that, The coupling (2) is covered with a bell-shaped cover.

4. The anti-reverse rotation protection device for a three-screw pump based on electrical phase sequence according to claim 3, characterized in that, The three-phase motor (3) is equipped with a base.

5. The anti-reverse rotation protection device for a three-screw pump based on electrical phase sequence according to claim 2, characterized in that, The current conversion unit incorporates overcurrent protection components and an AC-DC conversion circuit.

6. The anti-reverse rotation protection device for a three-screw pump based on electrical phase sequence according to claim 5, characterized in that, The SSR relay is a three-phase solid-state relay module, which has a built-in heat sink and zero-crossing trigger circuit.

7. The anti-reverse rotation protection device for a three-screw pump based on electrical phase sequence according to claim 6, characterized in that, The phase sequence determination circuit includes a phase sequence comparator composed of an operational amplifier.

8. A method for preventing reverse rotation of a three-screw pump based on electrical phase sequence, characterized in that, The anti-reverse rotation protection device for a three-screw pump based on electrical phase sequence as described in any one of claims 1 to 7 includes the following steps: S1: Power-on self-test procedure. When the device is powered on for the first time, the current conversion unit converts AC380V AC power into DC control voltage to power the control feedback module. The control feedback module initializes and performs a self-test upon power-on. S2: Phase sequence identification and judgment steps, the phase sequence judgment circuit in the control feedback module collects the phase sequence signal of the three-phase power supply of the three-phase motor (3) in real time through the signal acquisition module, and judges whether the current power supply phase sequence is positive or negative. S3: Direction locking and execution steps. When the phase sequence is correct, the control feedback module outputs a valid direction locking signal, the SSR relay is turned on, and the motor rotates in the forward direction to drive the screw pump. When the phase sequence is incorrect, the control feedback module immediately cancels the direction locking signal and outputs an interlock feedback signal. The SSR relay instantly disconnects the motor main circuit to prevent reverse rotation and sends a phase sequence fault alarm signal at the same time. S4: Operation monitoring steps. During the entire normal operation of the equipment, the control feedback module continuously monitors the power phase sequence status in real time. When an abnormal change in phase sequence is detected, the operation of the phase sequence error condition in S3 is immediately executed.

9. The method for preventing reverse rotation of a three-screw pump based on electrical phase sequence according to claim 8, characterized in that, The method for determining whether the current power supply phase sequence is positive or negative in step S2 is as follows: detect the voltage phase difference between phases AB and BC of the three-phase power supply of the three-phase motor (3). When both detection results are high, it is determined to be positive phase sequence; otherwise, it is determined to be negative phase sequence.

10. The method for preventing reverse rotation of a three-screw pump based on electrical phase sequence according to claim 9, characterized in that, In step S3, the phase sequence fault alarm signal displays the fault type and retains the fault record through the human-machine interaction module.

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