CN-115494379-B - Method for detecting star-sealing contactor for elevator based on control of permanent magnet synchronous motor by frequency converter

Abstract

The invention discloses a detection method of a star sealing contactor for an elevator, which comprises the following steps of firstly, keeping a PM motor to stop and keeping a main contact of the star sealing contactor closed when no output contactor exists, entering a second step, closing the output contactor to keep the PM motor to stop and keeping the main contact of the star sealing contactor closed when the output contactor exists, entering the second step, outputting a smaller voltage by any two or three of a U phase, a V phase and a W phase of a frequency converter, entering the third step, and detecting a star sealing function according to information related to phase currents. In addition, the invention also discloses a detection method of the star-sealing contactor for the elevator with the output contactor. The invention can detect whether the star-sealing contactor for the elevator is in an effective state, and does not need to release a brake, thereby having no safety risk.

Inventors

• ZHOU GENFU
• YANG YAJUN

Assignees

• 永大电梯设备（中国）有限公司

Dates

Publication Date

20260505

Application Date

20220915

Claims (20)

1. 1. The detecting method of the star sealing contactor for the elevator based on the frequency converter control permanent magnet synchronous motor is characterized by comprising the following steps: When the output contactor is arranged, the output contactor is closed, and the PM motor is kept to be stopped, the main contact of the star seal contactor is kept to be closed, and the step two is carried out; step two, outputting a smaller voltage by any two or three phases of a U phase, a V phase and a W phase of the frequency converter, and entering a step three; Step three, detecting a star sealing function according to the information related to the first phase current; the star sealing function detection according to the information related to the first phase current comprises the steps of judging that the information related to the phase current of any one of the U phase, the V phase and the W phase is compared with a threshold A, judging that the star sealing function is normal and ending if the information is close to the threshold A, and judging that the star sealing function is abnormal and ending if the information is not close to the threshold A.
2. 2. The method for detecting the star seal contactor for the elevator based on the permanent magnet synchronous motor controlled by the frequency converter according to claim 1, wherein in the second step, if any two phases of the U phase, the V phase and the W phase of the frequency converter output a smaller voltage, the second step and the third step are required to be repeated twice, and any two phases of the two phases are different.
3. 3. The method for detecting a star seal contactor for an elevator based on a frequency converter controlled permanent magnet synchronous motor according to claim 1, wherein when there is an output contactor, the steps of: step four, opening a three-phase normally open contact of the output contactor, and entering a step five; step five, keeping the PM motor to stop and the main contact of the star-sealing contactor to be closed, and entering a step six; Step six, outputting a larger voltage by any two or three phases of the U phase, the V phase and the W phase of the frequency converter, and entering a step seven; step seven, detecting the position of the star-sealed contactor according to the information related to the second phase current; the star sealing contactor position detection according to the information related to the second phase current comprises the steps of judging that the information related to the phase current of any one of the U phase, the V phase and the W phase is compared with a threshold value B, judging that the star sealing contactor is connected to the rear end of the output contactor if the information related to the phase current of any one of the U phase, the V phase and the W phase is close to the threshold value B, and judging that the star sealing contactor is connected to the front end of the output contactor and is corresponding to correction if the information related to the phase current of any one of the U phase, the V phase and the W phase is not close to the threshold value B.
4. 4. The method for detecting the star-sealed contactor for the elevator based on the frequency converter controlled permanent magnet synchronous motor according to claim 3, wherein in the sixth step, if any two phases of the U phase, the V phase and the W phase of the frequency converter output a larger voltage, the sixth step and the seventh step are required to be repeated twice, and any two phases of the two phases are different.
5. 5. The detecting method of the star seal contactor for the elevator based on the frequency converter control permanent magnet synchronous motor is characterized by comprising the following steps of: step one, a three-phase normally open contact of an output contactor is disconnected, and step two is carried out; Step two ', keeping the PM motor to stop and close the main contact of the star-sealed contactor, and entering a step three'; Step three ', namely outputting a larger voltage by any two or three phases of a U phase, a V phase and a W phase of the frequency converter, and entering a step four'; Fourthly', detecting the position of the star-sealed contactor according to the information related to the second phase current; the star sealing contactor position detection according to the information related to the second phase current comprises the steps of judging that the information related to the phase current of any one of the U phase, the V phase and the W phase is compared with a threshold value B, judging that the star sealing contactor is connected to the rear end of the output contactor if the information related to the phase current of any one of the U phase, the V phase and the W phase is close to the threshold value B, and judging that the star sealing contactor is connected to the front end of the output contactor and is corresponding to correction if the information related to the phase current of any one of the U phase, the V phase and the W phase is not close to the threshold value B.
6. 6. The method for detecting a star-sealed contactor for an elevator based on a frequency converter controlled permanent magnet synchronous motor according to claim 5, wherein in the third step ', if any two of the U-phase, V-phase and W-phase of the frequency converter output a larger voltage, the third step ' and the fourth step ' are repeated twice, and any two of the two phases are different.
7. 7. The method for detecting a star seal contactor for an elevator based on a frequency converter controlled permanent magnet synchronous motor according to claim 5, further comprising the steps of, after the star seal contactor is connected to the rear end of the output contactor: closing an output contactor, keeping a main contact closing state of a star-closing contactor when the PM motor is stopped, and entering a step six'; step six ', outputting a smaller voltage by any two or three phases of the U phase, the V phase and the W phase of the frequency converter, and entering a step seven'; and seventhly, detecting a star sealing function according to the information related to the first phase current.
8. 8. The method for detecting a star-sealed contactor for an elevator based on a frequency converter controlled permanent magnet synchronous motor according to claim 7, wherein in the step six ', if any two of the U-phase, V-phase and W-phase of the frequency converter output a smaller voltage, the steps six ' and seven ' are repeated twice, and any two of the two phases are different.
9. 9. A detection method of a star-sealing contactor for an elevator based on a frequency converter control permanent magnet synchronous motor is characterized by comprising the following steps when an output contactor exists, when the star-sealing detection adopts a sliding method and the output contactor is closed in hardware, the brake can be released, and the detection method comprises the following steps: Step one, a three-phase normally open contact of an output contactor is disconnected, and step two is carried out; Step two, keeping the PM motor to stop and the main contact of the star-sealing contactor to be closed, and entering a step three; step three, outputting a larger voltage by any two or three phases of a U phase, a V phase and a W phase of the frequency converter, and entering a step four; Fourthly, detecting the position of the star-sealed contactor according to the information related to the second phase current; the star sealing contactor position detection according to the information related to the second phase current comprises the steps of judging that the information related to the phase current of any one of the U phase, the V phase and the W phase is compared with a threshold value B, judging that the star sealing contactor is connected to the rear end of the output contactor if the information related to the phase current of any one of the U phase, the V phase and the W phase is close to the threshold value B, and judging that the star sealing contactor is connected to the front end of the output contactor and is corresponding to correction if the information related to the phase current of any one of the U phase, the V phase and the W phase is not close to the threshold value B.
10. 10. The method for detecting the star seal contactor for the elevator based on the frequency converter controlled permanent magnet synchronous motor according to claim 9, wherein in the third step ", if any two of the U phase, the V phase and the W phase of the frequency converter output a larger voltage, the third step and the fourth step need to be repeated twice, and any two of the two phases are different.
11. 11. The method for detecting the star-sealing contactor for the elevator based on the frequency converter controlled permanent magnet synchronous motor according to claim 7, wherein the star-sealing function detection according to the information related to the first phase current comprises the steps of judging that the information related to the phase current of any one of a U phase, a V phase and a W phase is compared with a threshold A, judging that the star-sealing function is normal if the information is close to the threshold A, and ending if the information is not close to the threshold A, judging that the star-sealing function is abnormal.
12. 12. The method for detecting a star-sealed contactor for an elevator based on a frequency converter controlled permanent magnet synchronous motor according to claim 3, 4, 5, 6, 9 or 10, wherein the larger voltage is characterized in that a non-zero current is generated when the frequency converter output is shorted.
13. 13. The method for detecting the star seal contactor for the elevator based on the frequency converter controlled permanent magnet synchronous motor of claim 12, wherein the larger voltage is characterized in that the time difference of the frequency converter outputting the two-phase upper tube or lower tube driving signal is larger than the voltage outputted by the set dead time Td.
14. 14. The method for detecting star-sealed contactors for elevator control of permanent magnet synchronous motor based on frequency converter according to claim 1, 2, 7 or 8, wherein the smaller voltage is two-phase or three-phase control, the output voltage is such that non-zero current is generated when the output is not short-circuited or partially short-circuited, and near zero current is generated when the output is short-circuited.
15. 15. The method for detecting a star-sealed contactor for an elevator based on a permanent magnet synchronous motor controlled by a frequency converter according to claim 14, wherein the smaller voltage is characterized in that when the phase current is close to zero, the time difference of the frequency converter outputting the two-phase upper tube or lower tube driving signal is smaller than the voltage outputted by the set dead time Td.
16. 16. The method for detecting a star seal contactor for an elevator based on a frequency converter controlled permanent magnet synchronous motor according to claim 1,2, 7 or 8, wherein the information related to the first phase current is one or a combination of any two of phase current itself, phase current difference, phase current sum, frequency, impedance and voltage.
17. 17. The method for detecting a star-sealed contactor for an elevator based on a frequency converter controlled permanent magnet synchronous motor according to claim 3 or 4 or 5 or 6 or 9 or 10, wherein the information related to the second phase current is one or a combination of any two of phase current itself, difference of phase currents, sum of phase currents, frequency, impedance and voltage.
18. 18. A method for detecting a star-sealed contactor for an elevator based on a frequency converter controlled permanent magnet synchronous motor according to claim 1 or 11, wherein the threshold value a is zero.
19. 19. A method for detecting a star-sealed contactor for an elevator based on a frequency converter controlled permanent magnet synchronous motor according to claim 3, 5 or 9, wherein the threshold B is zero.
20. 20. The detecting method for the star seal contactor for the elevator based on the frequency converter control permanent magnet synchronous motor according to claim 1,2, 7 or 8, wherein the smaller voltage can be compensated by adopting a control method of compensating through current feedback, so that when the output current approaches zero, the compensation voltage is small or approaches to 0, the compensation value becomes larger as the output current becomes larger, and the final compensation voltage is a limit value.

Description

Method for detecting star-sealing contactor for elevator based on control of permanent magnet synchronous motor by frequency converter Technical Field The invention relates to the technical field of detection of a star-sealing contactor of an elevator, in particular to a detection method of a star-sealing contactor for an elevator based on a frequency converter control permanent magnet synchronous motor. Background With the development of elevator technology, the safety requirement on the elevator is higher and higher, in order to ensure that the elevator can effectively reduce or limit the elevator sliding speed, three-phase input of a short-circuit traction motor (permanent magnet synchronous motor) is generally adopted, and the braking force generated by the permanent magnet of the permanent magnet synchronous motor (PM motor) is utilized to reduce or limit the elevator sliding speed (namely, the star sealing technology). Referring to fig. 1, a common star sealing method of the elevator control system at present adopts a star sealing contactor, and the star sealing contactor is added between a frequency converter and a PM motor to realize three-phase input of the short-circuit PM motor. In general, the star sealing function detection of an elevator control system mainly carries out the star sealing function detection through an auxiliary contact of a star sealing contactor. However, when the star sealing function is detected only through the auxiliary contact of the star sealing contactor, once the star sealing contactor is damaged, the star sealing contactor is not replaced or the circuit is manually changed for various reasons, and the action signals of other contactors are connected to the star sealing function detection port, so that the action condition of the star sealing contactor is not actually detected by the monitoring point. Or when the U-phase or V-phase or W-phase or short wire connected to the main contact of the star-sealing contactor is removed or the circuit is interrupted, the actual star-sealing function does not exist although the contactor has action. The invention discloses a detection method and a detection device for a star-sealing contactor for an elevator, which are disclosed in Chinese patent application publication No. CN114415007A, and are used for judging whether a star-sealing function is qualified by releasing a brake (namely, opening a band-type brake) to slide in a preset time or not. However, the method needs to release the brake (i.e. the band-type brake is opened), a certain risk exists, whether a person exists in the carriage or not needs to be judged, and the preset time and the preset speed of the method are complex to obtain. In addition, chinese patent application publication No. CN114715749a discloses an automatic detection method, system, device and storage medium for a star-sealing function of an elevator, where the automatic detection method for a star-sealing function of an elevator is applied to a control system of an elevator, and when a star-sealing function detection instruction is detected, target service floor information of the elevator is obtained, and after an elevator car is controlled to run to a target floor corresponding to the target service floor information, the star-sealing module is controlled to take effect, so that the elevator car enters a car-sliding state, a car-sliding speed or a car-sliding distance of the elevator car in the car-sliding state is obtained, and whether the star-sealing function of the elevator meets a preset requirement is determined based on the car-sliding speed or the car-sliding distance. The method also needs to release the brake (namely the band-type brake is opened), has a certain risk, needs to run to a specific floor, and cannot judge whether the star sealing contactor is connected to the front end of the output contactor or not because the output contactor needs to be closed when the vehicle is running, so that the star sealing function is invalid. The Chinese patent application publication No. CN115009949A discloses a detection method of the star sealing state of an elevator, which comprises the steps that ① the detection unit detects the power supply state of a power supply circuit, ② when the power supply circuit is changed from power on to power off, the main controller controls the detection switch to be closed so as to input a low-voltage variable-frequency alternating-current power supply to the star sealing circuit, and detects the current value I in the detection switch circuit, ③ when the current value I in the circuit is smaller than or equal to a threshold value Y, the main controller judges that the star sealing circuit is broken, further judges that the star sealing module is abnormal and sends a fault signal to the control system, the control system prohibits the operation of elevator equipment, and when the current value I in the circuit is larger than the threshold value Y, the main control