A device and method for quickly eliminating back electromotive force of a host motor

Abstract

The present invention belongs to the technical field of isotope separation, and specifically relates to a device and method for quickly eliminating the back electromotive force of a host motor. The present invention includes an inductor, a three-phase bridge rectifier circuit, a thyristor drive circuit module, and a cable. The inductor is connected to both ends of the three-phase bridge rectifier circuit, and the thyristor drive circuit module is connected to the gate end of the three-phase bridge rectifier circuit; one end of the cable is connected to the three-phase bridge rectifier circuit, and the other end is connected to the end of the host motor where the back electromotive force needs to be eliminated. The present invention can quickly eliminate the back electromotive force of the host motor, reduce the current passing through the host motor when eliminating the back electromotive force, and ensure the reliability of the device for eliminating the back electromotive force.

Description

Technical Field

[0001] The invention belongs to the technical field of isotope separation, and in particular relates to a device and method for quickly eliminating the back electromotive force of a main engine motor. Background Art

[0002] In the main engine operation factory, the main engine motor power supply interruption will generate back electromotive force, the higher the main engine speed, the higher the back electromotive force, some even reach hundreds of volts, which is extremely harmful to people and equipment, and the existence of back electromotive force will accelerate the main engine cycle speed, affecting the safe and reliable operation of the process system. Therefore, after the main engine motor power supply interruption, the back electromotive force must be eliminated immediately.

[0003] The device currently used to eliminate the back electromotive force of the host motor is to connect a three-phase contactor in parallel at the host motor end, and the elimination principle is also very simple. When the back electromotive force needs to be eliminated, the manual operation switch energizes the three-phase contactor coil and closes the main contacts. At this time, it is equivalent to short-circuiting the three-phase stator winding of the host motor. After short-circuiting, current will be generated in the stator coil of the host motor. The magnetic induction intensity reflected by this current on the rotor is opposite to the original magnetic induction intensity, so as to achieve the purpose of eliminating the rotor magnetism and thus eliminating the back electromotive force.

[0004] There are several disadvantages in using this device to eliminate back EMF: First, the three-phase contactor used is a mechanical structure device with a long action time, and the time to eliminate back EMF is also long. The existence of back EMF will accelerate the host's cycle speed, which is extremely detrimental to the safe and reliable operation of the process system; second, the short-circuit of the three-phase contactor alone will generate a large short-circuit current in the circuit. Since no measures are taken to limit the short-circuit current, the host motor may be damaged in the long run; third, the interlocking condition for the short-circuit of the three-phase contactor is that the section cabinet circuit breaker is disconnected. When the interlocking condition is not met, the back EMF cannot be eliminated, posing a major safety hazard. Summary of the invention

[0005] The technical problem solved by the present invention is to provide a device and method for quickly eliminating the back electromotive force of a host motor, which can quickly eliminate the back electromotive force of the host motor, reduce the current passing through the host motor when eliminating the back electromotive force, and ensure the reliability of the device for eliminating the back electromotive force.

[0006] The technical solution adopted by the present invention is:

[0007] A device for quickly eliminating the back electromotive force of a host motor comprises an inductor, a three-phase bridge rectifier circuit, a thyristor drive circuit module and a cable. The inductor is connected to two ends of the three-phase bridge rectifier circuit, and the thyristor drive circuit module is connected to the gate end of the three-phase bridge rectifier circuit. One end of the cable is connected to the three-phase bridge rectifier circuit, and the other end is connected to the host motor end where the back electromotive force needs to be eliminated.

[0008] The three-phase bridge rectifier circuit includes a first thyristor, a second thyristor, a third thyristor, a fourth thyristor, a fifth thyristor and a sixth thyristor; one end of the inductor is connected to the anode ends of the second thyristor, the fourth thyristor and the sixth thyristor, and the other end of the inductor is connected to the cathode ends of the first thyristor, the third thyristor and the fifth thyristor; the cathode ends of the second thyristor, the fourth thyristor and the sixth thyristor are respectively connected to the anode ends of the fifth thyristor, the third thyristor and the first thyristor.

[0009] The cables include three cables, one end of which is connected to the lines respectively connected to the cathode ends of the second thyristor, the fourth thyristor, and the sixth thyristor and the anode ends of the fifth thyristor, the third thyristor, and the first thyristor, and the other end is connected to the host motor end where the back electromotive force needs to be eliminated.

[0010] The thyristor drive circuit module sends a trigger signal to the first thyristor, the second thyristor, the third thyristor, the fourth thyristor, the fifth thyristor and the sixth thyristor of the three-phase bridge fully controlled rectifier circuit, and turns on the thyristors in turn in the conduction order of the first thyristor → the second thyristor → the third thyristor → the fourth thyristor → the fifth thyristor → the sixth thyristor.

[0011] The first thyristor, the second thyristor, the third thyristor, the fourth thyristor, the fifth thyristor and the sixth thyristor are 60 degrees out of phase with each other, and two thyristors are turned on at the same time at each moment.

[0012] The DC side inductor limits the short-circuit current, thereby eliminating the back electromotive force of the host motor.

[0013] The back electromotive force quick elimination device is connected to the lower end of the isolating switch through a cable, the upper end of the isolating switch is connected to the host motor, the host motor is powered by a power supply device, and the power supply device is connected to the back electromotive force quick elimination device through a signal line.

[0014] The power supply device supplies power to the host motor, the isolating switch is in a closed state, and the back-electromotive force rapid elimination device does not work; when the power supply device is started, stopped, or the back-electromotive force needs to be manually eliminated, a signal is immediately sent to the back-electromotive force rapid elimination device to put it in a working state to eliminate the back-electromotive force of the host motor.

[0015] A method for quickly eliminating back electromotive force of a host motor comprises the following steps:

[0016] S1, the power supply device is ready to start to supply power to the host motor

[0017] Connect the back-electromotive force quick elimination device to the lower end of the isolating switch, and the upper end of the isolating switch is connected to the host motor. The host motor is powered by the power supply device, and the power supply device is connected to the back-electromotive force quick elimination device through a signal line. Close the isolating switch between the back-electromotive force quick elimination device and the host motor; press the start button of the power supply device, and the power supply device is ready to start supplying power to the host motor;

[0018] S2, the back electromotive force quick elimination device is automatically turned on, starts timing, and eliminates the back electromotive force

[0019] The power supply device sends a trigger signal to the back electromotive force quick elimination device, starts timing for 5 seconds, turns it on for 5 seconds, and the back electromotive force elimination device starts working to eliminate possible back electromotive force.

[0020] S3, when the timing time is up, the back electromotive force quick elimination device automatically disconnects

[0021] When the 5s timing is up, the power supply device stops sending level signals to the back electromotive force rapid elimination device, and the back electromotive force rapid elimination device stops working;

[0022] S4, the power supply device stops, and the main engine motor is powered off

[0023] The power supply device starts to run and supplies power to the main engine motor, while locking the back electromotive force quick elimination device; when the stop button on the power supply device is pressed, the power supply device stops and the main engine motor is powered off.

[0024] When it is necessary to manually eliminate the back electromotive force, a trigger signal is sent to the back electromotive force quick elimination device, and the back electromotive force elimination device starts to work to eliminate the back electromotive force of the host motor.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] (1) The present invention provides a device and method for quickly eliminating the back electromotive force of a host motor. Before each power supply device is started, the back electromotive force quickly eliminating device is automatically turned on for a certain period of time to ensure that the power supply device has no back electromotive force when it is started, thereby ensuring the safe startup of the power supply device.

[0027] (2) The present invention provides a device and method for quickly eliminating the back electromotive force of a host motor. When the power supply device is operating normally, in order to prevent the back electromotive force quick elimination device from being actuated and causing a short circuit fault, the back electromotive force quick elimination device is locked with an operating signal of the power supply device to prevent it from being manually operated.

[0028] (3) The present invention provides a device and method for quickly eliminating the back electromotive force of a host motor. The action of the device for quickly eliminating the back electromotive force is interlocked with the inverter signal of the power supply device inverter. After the power supply device is shut down, the device for quickly eliminating the back electromotive force can automatically operate and be turned on within 20ms to instantly eliminate the back electromotive force of the host motor.

[0029] (4) The present invention provides a device and method for quickly eliminating the back electromotive force of a host motor. After the power supply device is shut down, the device for quickly eliminating the back electromotive force can be manually turned on or off.

[0030] (5) The present invention provides a device and method for quickly eliminating the back electromotive force of a host motor. Since the device for quickly eliminating the back electromotive force is connected in series with an inductor, the short-circuit current flowing through the host motor is limited, thereby ensuring the safety of the host motor when eliminating the back electromotive force. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 A schematic circuit diagram of a device for quickly eliminating back electromotive force of a host motor provided by the present invention;

[0032] Figure 2 A schematic diagram of the arrangement of a device for quickly eliminating back electromotive force of a main engine motor provided by the present invention;

[0033] Figure 3 A flow chart of a method for quickly eliminating back electromotive force of a host motor provided by the present invention;

[0034] In the figure: 1. first thyristor; 2. second thyristor; 3. third thyristor; 4. fourth thyristor; 5. fifth thyristor; 6. sixth thyristor; 7. inductor; 8. three-phase bridge fully controlled rectifier circuit; 9. thyristor drive circuit module; 10. cable; 11. back electromotive force fast elimination device; 12. isolating switch; 13. host motor; 14. power supply device. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0037] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0038] like Figure 1 As shown, a device for quickly eliminating the back electromotive force of a host motor provided by the present invention includes an inductor 7, a three-phase bridge rectifier circuit 8, a thyristor drive circuit module 9, and a cable 10. The three-phase bridge rectifier circuit 8 includes a first thyristor 1, a second thyristor 2, a third thyristor 3, a fourth thyristor 4, a fifth thyristor 5, and a sixth thyristor 6; one end of the inductor 7 is connected to the anode end of the second thyristor 2, the fourth thyristor 4, and the sixth thyristor 6, and the other end of the inductor 7 is connected to the cathode end of the first thyristor 1, the third thyristor 3, and the fifth thyristor 5 The cathode ends of the second thyristor 2, the fourth thyristor 4, and the sixth thyristor 6 are respectively connected to the anode ends of the fifth thyristor 5, the third thyristor 3, and the first thyristor 1; the thyristor drive circuit module 9 is connected to the gate end of the three-phase bridge rectifier circuit 8; the cable 10 includes three cables, one end of which is respectively connected to the cathode ends of the second thyristor 2, the fourth thyristor 4, and the sixth thyristor 6 and the anode ends of the fifth thyristor 5, the third thyristor 3, and the first thyristor 1, and the other end is connected to the host motor end whose back electromotive force needs to be eliminated.

[0039] When the back electromotive force needs to be eliminated, the thyristor driving circuit module 9 sends a trigger signal to the first thyristor 1, the second thyristor 2, the third thyristor 3, the fourth thyristor 4, the fifth thyristor 5, and the sixth thyristor 6 of the three-phase bridge full-controlled rectifier circuit 8, so that the six thyristors are turned on in turn in the turn-on sequence of the first thyristor 1→the second thyristor 2→the third thyristor 3→the fourth thyristor 4→the fifth thyristor 5→the sixth thyristor 6, with a phase difference of 60 degrees. At each moment, two thyristors are turned on at the same time, thereby realizing three-phase full-controlled rectification of the back electromotive force of the host motor and consuming energy in the loop. The DC side inductor 7 can limit the short-circuit current, thereby achieving the purpose of eliminating the back electromotive force of the host motor.

[0040] like Figure 2 As shown, the back electromotive force rapid elimination device 11 is connected to the lower end of the isolating switch 12 through a cable 10, and the upper end of the isolating switch 12 is connected to the host motor 13. The host motor 13 is powered by a power supply device 14, and the power supply device 14 is connected to the back electromotive force rapid elimination device 11 through a signal line.

[0041] During normal operation, the power supply device 11 supplies power to the host motor 13, the isolating switch 12 is in a closed state, and the back electromotive force quick elimination device 11 does not work. When the power supply device 14 is started, stopped, or the back electromotive force needs to be manually eliminated, a signal is immediately sent to the back electromotive force quick elimination device 11 to put it in a working state to eliminate the back electromotive force of the host motor. The function of the isolating switch 12 is to isolate the back electromotive force quick elimination device 11 for maintenance when it fails.

[0042] like Figure 3 As shown, a method for quickly eliminating the back electromotive force of a host motor provided by the present invention comprises the following steps:

[0043] S1, the power supply device is ready to start to supply power to the host motor

[0044] The back-electromotive force quick elimination device 11 is connected to the lower end of the isolating switch 12, the upper end of the isolating switch 12 is connected to the host motor 13, the host motor 13 is powered by the power supply device 14, the power supply device 14 is connected to the back-electromotive force quick elimination device 11 through a signal line, and the isolating switch 12 between the back-electromotive force quick elimination device 11 and the host motor 13 is closed; the start button of the power supply device 14 is pressed, and the power supply device 14 is ready to start supplying power to the host motor 13.

[0045] S2, the back electromotive force quick elimination device is automatically turned on, starts timing, and eliminates the back electromotive force

[0046] The power supply device 14 sends a trigger signal to the back-electromotive force rapid elimination device 11, starts timing for 5s, and turns it on for 5s. The back-electromotive force elimination device 1 starts working to eliminate possible back-electromotive force (the six thyristors are turned on in turn in the turn-on sequence of the first thyristor 1 → the second thyristor 2 → the third thyristor 3 → the fourth thyristor 4 → the fifth thyristor 5 → the sixth thyristor 6, with a phase difference of 60 degrees. At each moment, two thyristors are turned on at the same time, thereby realizing three-phase full-controlled rectification of the back-electromotive force of the host motor and consuming energy in the circuit. The DC side inductor 7 can limit the short-circuit current to achieve the purpose of eliminating the back-electromotive force of the host motor), ensuring the safe startup of the power supply device 14.

[0047] S3, when the timing time is up, the back electromotive force quick elimination device automatically disconnects

[0048] When the 5s timing is up, the power supply device 14 stops sending the level signal to the back electromotive force rapid elimination device 11, and the back electromotive force rapid elimination device 11 stops working.

[0049] S4, the power supply device stops, and the main engine motor is powered off

[0050] The power supply device 14 starts to supply power to the host motor 13 and locks the back electromotive force quick elimination device 11 at the same time; the stop button on the power supply device 14 is pressed, the power supply device 14 stops, and the host motor 13 is powered off.

[0051] When it is necessary to manually eliminate the back electromotive force, a trigger signal is sent to the back electromotive force quick elimination device 11, and the back electromotive force elimination device 1 starts to work to eliminate the back electromotive force of the host motor.

[0052] When the back electromotive force quick elimination device 11 fails, the isolating switch 12 is disconnected and repaired.

[0053] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0054] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A device for quickly eliminating the back electromotive force of a host motor, characterized in that: The invention comprises an inductor (7), a three-phase bridge rectifier circuit (8), a thyristor drive circuit module (9), and a cable (10); the inductor (7) is connected to two ends of the three-phase bridge rectifier circuit (8); the thyristor drive circuit module (9) is connected to a gate terminal of the three-phase bridge rectifier circuit (8); one end of the cable (10) is connected to the three-phase bridge rectifier circuit (8), and the other end is connected to a main motor terminal whose back electromotive force needs to be eliminated.

2. The device for quickly eliminating the back electromotive force of the host motor according to claim 1, characterized in that: The three-phase bridge rectifier circuit (8) comprises a first thyristor (1), a second thyristor (2), a third thyristor (3), a fourth thyristor (4), a fifth thyristor (5), and a sixth thyristor (6); one end of the inductor (7) is connected to the anode ends of the second thyristor (2), the fourth thyristor (4), and the sixth thyristor (6), and the other end of the inductor (7) is connected to the cathode ends of the first thyristor (1), the third thyristor (3), and the fifth thyristor (5); the cathode ends of the second thyristor (2), the fourth thyristor (4), and the sixth thyristor (6) are respectively connected to the anode ends of the fifth thyristor (5), the third thyristor (3), and the first thyristor (1).

3. The device for quickly eliminating the back electromotive force of the host motor according to claim 2, characterized in that: The cable (10) includes three cables, one end of which is connected to the lines respectively connected to the cathode ends of the second thyristor (2), the fourth thyristor (4), and the sixth thyristor (6) and the anode ends of the fifth thyristor (5), the third thyristor (3), and the first thyristor (1), and the other end is connected to the host motor end whose back electromotive force needs to be eliminated.

4. The device for quickly eliminating the back electromotive force of the host motor according to claim 3, characterized in that: The thyristor drive circuit module (9) sends a trigger signal to the first thyristor (1), the second thyristor (2), the third thyristor (3), the fourth thyristor (4), the fifth thyristor (5) and the sixth thyristor (6) of the three-phase bridge full-controlled rectifier circuit (8), so that the thyristors are turned on in turn in the turn-on sequence of the first thyristor (1) → the second thyristor (2) → the third thyristor (3) → the fourth thyristor (4) → the fifth thyristor (5) → the sixth thyristor (6).

5. The device for quickly eliminating the back electromotive force of the host motor according to claim 4, characterized in that: The first thyristor (1), the second thyristor (2), the third thyristor (3), the fourth thyristor (4), the fifth thyristor (5) and the sixth thyristor (6) have a phase difference of 60 degrees, and two thyristors are turned on at the same time at each moment.

6. The device for quickly eliminating the back electromotive force of the host motor according to claim 1, characterized in that: The DC side inductor (7) limits the short-circuit current, thereby achieving the purpose of eliminating the back electromotive force of the main engine motor.

7. The device for quickly eliminating the back electromotive force of the host motor according to claim 1, characterized in that: The back electromotive force quick elimination device (11) is connected to the lower end of an isolating switch (12) via a cable (10); the upper end of the isolating switch (12) is connected to a host motor (13); the host motor (13) is powered by a power supply device (14); and the power supply device (14) is connected to the back electromotive force quick elimination device (11) via a signal line.

8. The device for quickly eliminating the back electromotive force of the host motor according to claim 7, characterized in that: The power supply device (11) supplies power to the host motor (13), the isolating switch (12) is in a closed state, and the back electromotive force quick elimination device (11) does not work; when the power supply device (14) is started, stopped, or the back electromotive force needs to be manually eliminated, a signal is immediately sent to the back electromotive force quick elimination device (11) to put it in a working state, thereby eliminating the back electromotive force of the host motor.

9. A method for quickly eliminating the back electromotive force of a host motor, characterized in that: The steps include: S1, the power supply device is ready to start to supply power to the host motor The back electromotive force quick elimination device (11) is connected to the lower end of the isolating switch (12), the upper end of the isolating switch (12) is connected to the main engine motor (13), the main engine motor (13) is powered by a power supply device (14), the power supply device (14) is connected to the back electromotive force quick elimination device (11) via a signal line, the isolating switch (12) between the back electromotive force quick elimination device (11) and the main engine motor (13) is closed; the start button of the power supply device (14) is pressed, and the power supply device (14) is ready to start supplying power to the main engine motor (13); S2, the back electromotive force quick elimination device is automatically turned on, starts timing, and eliminates the back electromotive force The power supply device (14) sends a trigger signal to the back electromotive force quick elimination device (11), starts timing for 5 seconds, turns it on for 5 seconds, and the back electromotive force elimination device (11) starts working to eliminate possible back electromotive force. S3, when the timing time is up, the back electromotive force quick elimination device automatically disconnects When the 5s time is up, the power supply device (14) stops sending a level signal to the back electromotive force rapid elimination device (11), and the back electromotive force rapid elimination device (11) stops working; S4, the power supply device stops, and the main engine motor is powered off The power supply device (14) starts to operate and supplies power to the main engine motor (13), while locking the back electromotive force quick elimination device (11); by pressing a stop button on the power supply device (14), the power supply device (14) stops, and the main engine motor (13) is powered off.

10. The method according to claim 9, characterized in that When it is necessary to manually eliminate the back electromotive force, a trigger signal is sent to the back electromotive force quick elimination device (11), and the back electromotive force elimination device (1) starts to work to eliminate the back electromotive force of the host motor.

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