Pump station synchronous motor electric turning gear

Abstract

The utility model relates to an electrical barring gear of a pump station synchronous motor, which relates to the technical field of pump station synchronous motors and comprises three silicon controlled rectifier circuits, three follow current loops and an electrical barring gear control circuit. Wherein the outputs of the three silicon controlled rectifier circuits are respectively connected to a three-phase winding of a motor stator; the follow current loop is electrically connected with the silicon controlled rectifier circuit; the follow current loop is used for providing a conduction loop for the inductive load after the direct current is cut off; and the electrical barring gear control circuit is used for controlling and triggering a silicon controlled rectifier in the silicon controlled rectifier rectifying circuit and controlling the action logic of the electrical barring gear. The purpose of rotation is achieved through the principle that like polarities repel and opposite polarities attract in the magnetic field, and the technical problems existing in the prior art are solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of pump station synchronous motor, and particularly relates to an electrical turning gear of pump station synchronous motor. BACKGROUND

[0002] In the operation of a pump station, the starting problem of a vertical shaft flow pump synchronous motor is crucial.

[0003] However, the situation of difficult starting of a synchronous motor occurs from time to time, which brings many challenges to the normal operation of the pump station. When the synchronous motor of a drainage unit encounters difficulty in starting or cannot start, the conventional and regular treatment method has obvious disadvantages. The common method of lifting the rotor has many problems. If the lifting-rotor device is not designed during the construction stage of the pump station, the on-site arrangement is difficult to implement, such as in a lower steep gate pump station. The device was not designed during construction, and now it cannot be installed and used on site. Even if the lifting-rotor device is used manually, there are still many problems. The structure of the equipment causes the jack to have no force point. During the rising process of the rotor, the small gap between the tiles is extremely easy to cause deviation, which causes the rotor to be unevenly stressed, and further damages the equipment. Moreover, the operation position is high, and manual operation has a great safety risk.

[0004] The manual mechanical turning gear method also has many problems. This method needs to remove all equipment on the top of the motor in order to install the turning gear equipment and the lengthened lever. Not only is the workload huge, but the recovery work after turning is also very tedious. Moreover, since the operation is performed manually on the top of the motor, a large number of operators are needed, the operation position is narrow, it is not convenient to push the lever, and a large number of personnel gather on the top of the motor, which has serious safety hazards.

[0005] In summary, the existing methods for solving the difficulty in starting the vertical shaft flow pump synchronous motor have certain limitations. How to solve this technical problem is a technical problem that needs to be overcome by those skilled in the art. CONTENT OF THE UTILITY MODEL

[0006] In order to at least partially solve the above technical problems, the present application provides an electrical turning gear of a pump station synchronous motor.

[0007] An electrical turning gear of a pump station synchronous motor comprises three silicon-controlled rectifier circuits, three freewheeling circuits and an electrical turning gear control circuit, wherein,

[0008] The outputs of the three silicon-controlled rectifier circuits are connected to the three-phase stator windings of the motor, respectively.

[0009] The freewheeling circuit is electrically connected to the silicon-controlled rectifier circuit, and is used to provide a conduction loop for the inductive load after the direct current is cut off.

[0010] The electrical turning gear control circuit is used to control the triggering of the silicon-controlled rectifiers in the silicon-controlled rectifier circuit and the action logic of the electrical turning gear.

[0011] By employing the above technical solution, direct current is applied to the three-phase stator windings of the motor: first, a direct current is applied to phase A (phase AB), and the rotor magnetic field interacts with the magnetic field generated by the stator phase A (or AB), causing the rotor to rotate until the rotor magnetic field axis coincides with the stator magnetic field axis. Then, direct current is applied to phase B (phase BC) and phase C (phase CA), and the rotor rotates again until the magnetic fields reach a new coincidence line. By repeating this cycle, the rotor can complete a full revolution, solving the problem of difficult starting.

[0012] Optionally, the thyristor rectifier circuit consists of a three-phase fully controlled rectifier bridge and an RC snubber circuit; each thyristor rectifier circuit includes six thyristors; every two thyristors form a branch; the three branches are connected in parallel; the anode of the first thyristor in each branch is connected to the positive terminal of the power supply, and the anode of the second thyristor is connected to the cathode of the first thyristor; the RC snubber circuit includes a resistor R and a capacitor C connected in series; each thyristor is connected in parallel with an RC snubber circuit.

[0013] Optionally, the freewheeling circuit includes a diode and a contactor; the anode of the diode is connected to the positive terminal of the power supply; the contactor is connected between the diode and one of the motor stator windings.

[0014] Optionally, the three thyristor rectifier circuits are referred to as the first thyristor rectifier circuit, the second thyristor rectifier circuit, and the third thyristor rectifier circuit.

[0015] The freewheeling circuit connected to the first thyristor rectifier circuit is referred to as the first freewheeling circuit; the first freewheeling circuit includes a first diode MD1 and a first contactor KM1; the first contactor KM1 is connected between the first diode MD1 and phase A of the motor stator winding;

[0016] The freewheeling circuit connected to the second thyristor rectifier circuit is called the second freewheeling circuit; the second freewheeling circuit includes the second diode MD2 and the second contactor KM2; the second contactor KM2 is connected between the second diode MD2 and item B of the motor stator winding;

[0017] The freewheeling circuit connected to the third thyristor rectifier circuit is referred to as the third freewheeling circuit; the third freewheeling circuit includes the third diode MD3 and the third contactor KM3; the third contactor KM3 is connected between the third diode MD3 and the C term of the motor stator winding.

[0018] Optionally, the control circuit of the electric turning gear includes a silicon controlled rectifier (SCR) trigger and a programmable controller (PLC); the SCR trigger is used to control the triggering of the SCR; the PLC is used to control the operating logic of the entire electric turning gear.

[0019] Optionally, the device may also include a display screen and operation buttons. Attached Figure Description

[0020] Fig. 1 This is an overall circuit diagram of a pump station synchronous motor electric turning device according to an embodiment of this application;

[0021] Fig. 2 This is a circuit diagram of the thyristor rectifier circuit and the freewheeling circuit of a synchronous motor turning device for a pumping station according to an embodiment of this application;

[0022] Fig. 3 This is a diagram illustrating the implementation process of an embodiment of this application. Detailed Implementation

[0023] The following is in conjunction with the appendix Figs. 1-3 The present application will be further described with reference to specific embodiments:

[0024] This application discloses an electric turning device for a pump station synchronous motor, comprising: three thyristor rectifier circuits, three freewheeling circuits, and an electric turning device control circuit; wherein...

[0025] The outputs of the three thyristor rectifier circuits are respectively connected to the three-phase windings of the motor stator;

[0026] The freewheeling circuit is electrically connected to the thyristor rectifier circuit; the freewheeling circuit is used to provide a conduction path for the inductive load after the DC current is cut off.

[0027] The control circuit of the electric turning device is used to control and trigger the thyristor in the thyristor rectifier circuit and to control the operation logic of the electric turning device.

[0028] As one embodiment of the synchronous motor electric turning device for a pump station, the thyristor rectifier circuit consists of a three-phase fully controlled rectifier bridge and an RC snubber circuit; each thyristor rectifier circuit includes six thyristors; every two thyristors form a branch; the three branches are connected in parallel; the anode of the first thyristor in each branch is connected to the positive terminal of the power supply, and the anode of the second thyristor is connected to the cathode of the first thyristor; the RC snubber circuit includes a resistor R and a capacitor C connected in series; each thyristor is connected in parallel with an RC snubber circuit.

[0029] In one embodiment of a synchronous motor electric turning device for a pumping station, the freewheeling circuit includes a diode and a contactor; the positive terminal of the diode is connected to the positive terminal of the power supply; and the contactor is connected between the diode and one of the motor stator windings.

[0030] As one embodiment of the synchronous motor electric turning device for a pump station, the three thyristor rectifier circuits are referred to as the first thyristor rectifier circuit, the second thyristor rectifier circuit, and the third thyristor rectifier circuit.

[0031] The freewheeling circuit connected to the first thyristor rectifier circuit is referred to as the first freewheeling circuit; the first freewheeling circuit includes a first diode MD1 and a first contactor KM1; the first contactor KM1 is connected between the first diode MD1 and phase A of the motor stator winding;

[0032] The freewheeling circuit connected to the second thyristor rectifier circuit is called the second freewheeling circuit; the second freewheeling circuit includes the second diode MD2 and the second contactor KM2; the second contactor KM2 is connected between the second diode MD2 and item B of the motor stator winding;

[0033] The freewheeling circuit connected to the third thyristor rectifier circuit is referred to as the third freewheeling circuit; the third freewheeling circuit includes the third diode MD3 and the third contactor KM3; the third contactor KM3 is connected between the third diode MD3 and the C term of the motor stator winding.

[0034] As one embodiment of the electric turning device for synchronous motors in a pumping station, the control circuit of the electric turning device includes a thyristor trigger and a programmable controller; the thyristor trigger is used to control the triggering of the thyristor; the programmable controller is used to control the operation logic of the entire electric turning device.

[0035] As one embodiment of the synchronous motor electric turning device for a pumping station, the device also includes a display screen and operation buttons.

[0036] The following is a detailed explanation of the operating principles, combined with... Figs. 1-3 .

[0037] The electric turning device has "manual" mode and "automatic" mode.

[0038] 1) Manual working mode

[0039] Switch the operating mode to "Manual". First, press and hold the AB phase control button (keep pressing and holding). After KM1 activates, it will automatically trigger the AB phase thyristors to conduct, and DC current will flow into the stator AB phase windings, causing the rotor to rotate. When the rotor magnetic field coincides with the stator magnetic field axis, the rotor will stop rotating. At this point, you can release the AB phase button. KM1 will continue to activate and automatically provide freewheeling current to the AB phase windings. After a delay of T2, KM1 will disconnect. Then, press the BC phase and CA phase buttons in sequence to continuously rotate the rotor.

[0040] 2) Automatic working mode

[0041] A. Switch the operating mode handle to "automatic". After pressing the start button, KM1 will be automatically engaged and the AB phase thyristors will be automatically turned on. After a delay of T1 (Note: T1 delay is the time it takes to reach a new equilibrium after each rotation), the AB phase thyristors will be turned off. After a delay of T2 (Note: T2-T1 is the freewheeling time), KM1 will be disconnected.

[0042] B. KM2, KM3 and their corresponding thyristors are automatically engaged / disengaged in sequence to make the rotor rotate continuously.

[0043] C. Each cycle consists of energizing phases AB, BC, and CA. After the nth cycle (where n is the number of pole pairs of the motor), the rotor rotates one revolution.

[0044] In summary, the electrical turning device of this application has the following characteristics:

[0045] 1) Minimal operational workload. Simply connect the plant's power supply to the power supply side of the turning gear and connect the output of the turning gear to the three-phase winding of the motor, avoiding extensive disassembly and assembly work and simplifying operation.

[0046] 2) Adjustable speed. By adjusting the output voltage of the thyristor on the turning device, the magnitude of the stator magnetic field can be changed, and the turning speed can be increased or decreased.

[0047] 3) The turning process is safe and controllable. First, the turning device is placed on the ground, and the operator only needs to operate a simple button on the device to rotate the rotor, avoiding the safety risks associated with working at height. Second, only DC current needs to be applied to the stator / rotor, and the current / voltage is controllable and does not exceed the rated operating range. Finally, turning the rotor by applying current ensures uniform force distribution and stable rotor rotation, preventing equipment damage.

[0048] 4) Parameter setting is simple and quick. The parameters of the electric turning gear are set on the touch screen, which is simple and quick. There are three main parameters:

[0049] ① The conduction duration T1 of the thyristor in automatic mode;

[0050] ② KM connection duration T2 in automatic mode;

[0051] ③ KM delay disconnect time T3 in manual mode (i.e., the resume time in manual mode);

[0052] (Note: T2-T1 are the continuous flow times in automatic mode; T1 time needs to be adjusted according to the rotation speed.)

[0053] 5) Quickly adjust the rotation direction of the turning gear. The device has a "forward / reverse" switch handle. When the turning gear is in the opposite direction (or when it needs to be rotated in the opposite direction), the "forward / reverse" handle can be switched to correct the rotation direction immediately.

[0054] 6) The turning gear provides intuitive operating data. The turning gear is equipped with ammeters / voltmeters to directly monitor the electrical data of the three-phase windings.

[0055] 7) The maximum operating current of the electric turning device is 150A. Synchronous motors of other pump sets of the same type within this operating range are also applicable.

[0056] It should be noted that the above embodiments are only used to illustrate this application and are not intended to limit the technical solutions described in this application. Although this specification has described this application in detail with reference to the above embodiments, those skilled in the art should understand that they can still make modifications or equivalent substitutions to this application. All technical solutions and improvements that do not depart from the spirit and scope of this application should be covered within the scope of the claims of this application.

Claims

1. A pump station synchronous motor electrical turning gear characterized by, The application relates to an electric disc turning device control circuit. The output of the three controllable silicon rectifier circuits is connected to the three-phase stator winding of a motor. The freewheeling circuit is electrically connected to the controllable silicon rectifier circuit, and provides a conduction loop for the inductive load after DC is cut off. The electric disc turning device control circuit is used for controlling the triggering of the controllable silicon in the controllable silicon rectifier circuit and the action logic of the electric disc turning device. The controllable silicon rectifier circuit is composed of a three-phase full-control rectifier bridge and an RC resistance-capacitance absorption circuit.

2. A pump station synchronous motor electrical turning gear as claimed in claim 1, characterized in that, The freewheeling circuit comprises a diode and a contactor.

3. A pump station synchronous motor electrical turning gear as claimed in claim 2, characterised in that, The positive pole of the diode is connected to the positive pole of the power supply.

4. A pump station synchronous motor electrical turning gear as claimed in claim 3, characterised in that, The first controllable silicon rectifier circuit, the second controllable silicon rectifier circuit and the third controllable silicon rectifier circuit are denoted as the first controllable silicon rectifier circuit, the second controllable silicon rectifier circuit and the third controllable silicon rectifier circuit. The first freewheeling circuit connected to the first controllable silicon rectifier circuit comprises a first diode MD1 and a first contactor KM1. The second freewheeling circuit connected to the second controllable silicon rectifier circuit comprises a second diode MD2 and a second contactor KM2. The third freewheeling circuit connected to the third controllable silicon rectifier circuit comprises a third diode MD3 and a third contactor KM3.

5. A pump station synchronous motor electrical turning gear as claimed in claim 4, wherein, The electric disc turning device control circuit comprises a controllable silicon trigger and a programmable controller.

6. A pump station synchronous motor electrical turning gear as claimed in claim 5, characterised in that, The device further comprises a display screen and operation buttons.

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