[0033] like figure 2 As shown, it is a structural diagram of an embodiment of a system for controlling an elevator by using a permanent magnet synchronous motor according to the present invention. In this embodiment, the system includes a motor 23 , a holding brake 24 , a motor drive control unit 21 , and a main contactor 22 , wherein the motor drive control unit 22 is connected to an external power source and supplies power to the motor 23 via the main contactor 22 . The motor drive control unit 21 is also used to receive feedback information from the holding brake 24 , the motor 23 and the main contactor 22 , and control the closing and opening of the main contactor 22 and the opening and closing of the holding brake 24 .
[0034] like image 3 Shown is a schematic diagram of the structure of the motor drive control unit 21 . The motor drive control unit 21 includes a speed adjustment unit 211 , a current adjustment unit 212 , a current control unit 213 and a motor starting unit 214 . The speed adjustment unit 211 is used to adjust PI according to the speed feedback from the motor 23 ; the current adjustment unit 212 is used to adjust the current PI according to the current feedback of the motor 23 .
[0035] The current control unit 213 is used to output a detection current to the motor 23 after receiving the feedback signal that the main contactor 22 is closed. For example, after the main contactor 22 is closed, that is, after the motor drive control unit 21 collects the feedback signal that the main contactor 22 is closed through the auxiliary contact of the main contactor 22, the current control unit 213 gradually increases the current output to the motor 23, This process lasts for 75ms and the magnitude of its current increases linearly from 0 to 30% of the rated current of the motor 23 .
[0036] After the process of gradually increasing the current, the motor drive control unit 21 detects the actual feedback current of the motor 23 through the current detection unit 215 .
[0037] The motor starting unit 214 is used to restore the current output to the motor 23 to a normal starting state and open the holding brake when the actual feedback current is greater than or equal to the set threshold. When the feedback current is greater than or equal to the threshold set above, it indicates that the contacts of the main contactor 22 of the system are normal, so that the moving and closing mechanism of the elevator can operate normally. In this embodiment, the motor starting unit 214 reduces the current of the motor 23 (eg, in a linear manner) through a process of 75ms, restores the current to a normal starting state, and then opens the brake to control the elevator operation.
[0038] When the maximum amplitude output by the current control unit 213 is 30% of the rated current of the motor, the threshold set above may be 20% of the rated current of the motor 13 . Of course, the threshold value of the feedback current can also be specifically set according to the actual situation.
[0039] During the start-up process of the above system, before the brake is opened, it can be effectively detected whether there is abnormal contact contact of the main main contactor 22 . In addition, the current adopts a step-by-step change process, which avoids the sound generated by the too fast current change in the motor 23 .
[0040] In addition, the above system can also include an alarm unit (not shown in the figure), which is used for when the feedback current is less than the set threshold (at this time, the contacts of the main contactor 22 are abnormal, and the current cannot be transmitted through the main contactor). To the motor 23), an alarm is issued and the subsequent brake output is stopped.
[0041]In the above system, a motor stop unit (not shown in the figure) may also be included for gradually reducing the input current of the motor 23 to zero after the holding brake 24 is fully closed. When the brake 24 of the elevator is completely closed, the elevator no longer needs the torque of the motor 23 to maintain the balance of the elevator load, and is ready to remove the motor running command. At this time, the motor stop unit proposed by the present invention gradually reduces the current current through the time control of 300ms. is 0A (eg in a linear fashion).
[0042] In addition, the motor drive control unit in the above system can also include an elevator control logic unit, which is responsible for the control of the curve and logic when the elevator is running; the elevator peripheral signal collection and processing unit is used to complete the call of each floor in the elevator application. The collection and processing of peripheral signals such as information and safety signals; the man-machine interface is the interface for debugging and monitoring the elevator integrated controller.
[0043] like Figure 4 Shown is a flow chart of an embodiment of a method for controlling an elevator by using a permanent magnet synchronous motor according to the present invention. The method includes the following steps during the start-up phase of the elevator:
[0044] Step S41: After receiving the feedback signal that the main contactor is closed, output the detection current to the motor. In this step, the detection current is output to the motor so as to linearly increase to the maximum value within 75 milliseconds. In particular, the maximum value of the detection current may be 30% of the rated current of the motor.
[0045] Step S42: Detect the feedback current of the motor, if the feedback current is greater than or equal to the set threshold, then execute step S43, otherwise, execute step S44. In this step, the threshold value set above is 20% of the rated current of the motor.
[0046] Step S43: restore the current output to the motor to a normal starting state, and open the holding brake.
[0047] Step S44: alarm and stop the output of the brake.
[0048] In addition, in the above method, in order to reduce the noise generated by the sudden change of the motor current during the elevator stop phase, it can also include gradually reducing the input current of the motor to zero after the brake is completely closed during the elevator stop phase. The current output to the motor after the brake is fully closed can be reduced by linearly reducing from normal to zero within 300 milliseconds.
[0049] In the above-mentioned system and method, the manner of increasing or decreasing is not limited to a linear manner, and other function-changing manners may also be used.
[0050] The above description is only a preferred embodiment of the present invention, but the protection scope of the present invention is not limited to this. Substitutions should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.
