JP4470950B2 - Elevator system - Google Patents

Description

  The present invention relates to an elevator system, and more particularly to an elevator system capable of improving passenger safety with an existing system.

  When the elevator system is stopped, the car and the counterweight are held by the brake. If the brake breaks down and the braking force is insufficient, it becomes difficult to hold the car in the landing position. In order to cope with such a case, the elevator floor alignment apparatus described in Patent Document 1 (Japanese Patent Laid-Open No. 2002-20046) includes a linear output position detector in the car, and the car stops on the floor. Even if the stop position of the car is out of the landing error range due to an abnormal brake, the motor starts and moves the car into the landing error range.

  Moreover, in the elevator safety device described in Patent Document 2 (Japanese Patent Laid-Open No. 9-212285), a rope gripping device is used, the brake detector detects that the brake has been operated, and the door open / close detector is a car. When the door opening is detected and the speed detector detects that the car speed is equal to or higher than the predetermined speed, the rope gripping device is operated to grip the car and the counterweight.

  Furthermore, in the elevator control system described in Patent Document 3 (International Publication No. 2004/050523 pamphlet), the motor is rotated by the encoder when the car moves due to insufficient brake holding force while the brake is operating. The motor is driven to detect and generate a torque that prevents the motor from rotating.

Japanese Patent Laid-Open No. 2002-20046 JP-A-9-212285 International Publication No. 2004/050523 Pamphlet

  However, in the configuration of Patent Document 1, it is necessary to provide an expensive linear output position detector in the car. In particular, in an existing system that does not include a position detector, it is necessary to newly install an expensive position detector. Moreover, in the structure of patent document 2, it is necessary to newly install a rope holding | grip apparatus. In this case as well, an increase in cost and complexity of the mechanism are inevitable in that a new device is installed in addition to the existing system. Furthermore, in the configuration of Patent Document 3, since the electric power converter is started and the electric motor is operated after the car starts to move, the delay time until actual driving is increased. As a result, the moving amount of the car may be increased.

  The purpose of the present invention is to ensure the safety of passengers in the car by holding the car with the driving force of the electric motor without adding a new device to the existing system even in the event of a brake failure and without time delay It is to provide an elevator system that operates as much as possible. In addition, as a precaution, an elevator system including a safety mechanism that collects the landing position of a car and transmits it to a monitoring center is provided.

  As means for solving the above-described problem, even when the brake is operating, the power converter is operated to give zero as the speed command value. As another means, the landing position of the car is collected, and a history is recorded, and when a sign of abnormality appears, a warning is issued to the monitoring center.

  According to the above means, since the speed is fixed to zero by the holding force of the brake, almost no torque current flows. Further, when the electric motor is a permanent magnet motor, no exciting current is required, so that even if the power converter is operated at zero speed, almost no current flows and the power loss is extremely small. Furthermore, in the unlikely event of a brake failure, torque can be instantaneously applied by the power converter, so that the passenger car can be secured without moving and the passenger car can be secured. In addition, according to the other means, an abnormality sign can be detected.

  Therefore, according to the present invention, the safety of passengers can be greatly improved with the existing system.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 shows an elevator system according to a first embodiment of the present invention. At least a power converter 1, a motor 2 driven by the power converter 1, a sheave 3 that rotates with the operation of the motor 2, and a sheave 3 are hung. A car 4 that is connected to a rope and moves up and down as the sheave 3 rotates, a counterweight 5, a rotary encoder 6 that is attached to the motor 2 and detects the rotation of the motor shaft, and a motor that is used when passengers get on and off. 2 includes a brake 7 that holds the car 4 stationary, a controller 8 that generates a control signal for raising and lowering the car 4 and driving the brake 7, and a brake circuit 9 that opens and closes the brake 7 based on the control signal of the controller 8. The power converter 1 converts the commercial power of the power source 10 into power having an arbitrary frequency and drives the motor 2 smoothly. The drive signal of the power converter 1 is calculated by the controller 8 based on the output current information of the power converter 1 and the magnetic pole position signal and speed signal of the motor obtained from the rotary encoder 6. The car 4 is driven by the motor 2 via the sheave 3 and has an ascending / descending speed proportional to the rotation of the motor 2. The monitoring center 11 will be described later.

  FIG. 2 is a flowchart of the operation at the time of landing on the conventional car. When the car is landing, the car 4 is driven by the motor 2 to drive to the landing position of the target floor (step 12). When the car 4 arrives at the landing position, the brake 7 is closed and the car 4 is held (step 13). In general, the brake 7 is configured to press the brake pad with a spring force or the like. When the brake circuit 9 is not operating (when no signal is given to the brake 7), the brake 7 is in a braking state, and the brake 7 When a release signal is given from the circuit 9 to the brake 7, the braking force is released and the motor 2 can be driven. Since braking of the brake 7 can be controlled by the controller 8 via the brake circuit 9, in this embodiment, the braking state of the brake (the state in which the brake is closed) is driven by the brake, or the controller drives the brake. It is written as Normally, the shaft of the motor 2 does not operate while the brake 7 is being driven, and the speed / position signal transmitted from the rotary encoder 6 to the controller 8 does not change. For this reason, when the brake is driven, the main circuit of the power converter 1 is stopped and the door of the car 4 is opened (step 14). In this state, passengers can get on and off.

  FIG. 3 is a flowchart of the first landing operation of the first embodiment of FIG. Unlike the case of FIG. 2, the power converter is continuously driven even when the brake is being driven. First, the car 4 is driven by the motor 2 to the landing position of the target floor (step 15) in the same manner as in the operation flow chart of the conventional car landing in FIG. When reaching the landing position, the brake 7 is closed and the car 4 is held (step 16). Next, even when the brake is operating, the power converter is operated, zero is given as the speed command value, and the door is opened (step 17). When the door is open, the power converter continues to be driven with a speed command value of zero.

  FIG. 4 is a block diagram of the first landing operation of FIG. In this case, the controller 8 includes a brake drive processing unit 18, a power converter control calculation unit 19, and a door drive unit 20. When the brake is driven in step 16 of FIG. 3, the brake drive processor 18 gives a signal to the brake circuit 9 to drive the brake 7. The power converter control calculation unit 19 performs a control calculation of the power converter 1 and includes a speed control system 21, a current control system 22, and a PWM calculation unit 23 as control systems for controlling the power converter 1. The speed control system 21 calculates and outputs a torque command value (τ *) such that the difference value between the rotational speed of the motor and the speed command obtained from the rotary encoder 6 becomes zero. The torque command value is converted into a current command value, and the voltage command value is calculated by the current control system 22 so that the difference from the actually flowing current value becomes zero. The voltage command value is converted into an ON / OFF signal for controlling the power converter 1 by the PWM calculation unit 23. The control signal calculated by the PWM calculation unit 23 is transmitted to the drive circuit 24 of the power converter 1, and the drive circuit 24 drives the power converter main circuit 25 to operate the motor 2. Here, by setting the speed command value to zero, the speed control system 21 calculates a torque command value so that the rotational speed of the motor becomes zero, and the current control system 22, the PWM calculation unit 23, and the power converter 1 are operated. Through which the motor 2 can be stationary.

  In step 17 of FIG. 3, a zero command is given as a speed command value. However, in this case, since the speed is fixed to zero by the holding force of the brake, the torque generated by the motor 2 is extremely small and the torque command value output from the speed control system 21 is also small. For this reason, the electric current accompanying torque generation hardly flows. In addition, when the motor 2 is a permanent magnet motor, no excitation current is required, so that almost no current flows through the motor 2 even if the power converter 1 is operated so as to have zero speed. Therefore, the power loss is extremely small even when the power converter is continuously driven. Furthermore, even if the brake breaks down, torque can be applied instantaneously so that the rotational speed of the motor obtained from the rotary encoder 6 becomes zero, so that the car does not move and passenger safety is ensured. be able to. 3 is performed by the door drive unit 20.

The speed control system 21 of FIG. 4 generally uses so-called PI control that uses both proportional control and integral control, but there is a risk that errors may be accumulated by the integral control. In order to prevent this, the speed control system 21 in the continuous operation of the power converter in Step 17 of FIG. 3 may be configured to be implemented only by proportional control (P control). This has the effect of stably stopping the car.

  FIG. 5 is a flowchart of the second landing operation of the first embodiment of FIG. In the first landing operation of FIG. 3, even when the brake 7 is operating normally, the main circuit 25 of the power converter 1 is always driven, and a slight current continues to be output. Therefore, in the second landing operation, when there is no elevator call, the main circuit 25 of the power converter 1 is stopped. First, similarly to the operation in the flowchart of the first landing operation of FIG. 3, the car 4 is driven by the motor 2 to drive to the landing position of the target floor (step 26). When the vehicle arrives at, the brake 7 is closed and the car 4 is held (step 27). Next, the speed command value is set to zero and the power converter is continuously operated to open the door (step 28). When the passenger gets off, the door is closed (step 29). In a general elevator, if the next call does not occur even after a predetermined time has passed after the door is closed, a process of turning off the lighting in the car 4 is performed. In the second landing operation, a process of stopping the main circuit 25 of the power converter 1 is performed in accordance with this process (step 30). As a result, the drive time of the power converter 1 can be reduced, which is effective for reducing the amount of electricity used and suppressing fatigue deterioration of the main circuit 25.

  FIG. 6 is a flowchart of the third landing operation of the first embodiment of FIG. In the third landing operation, stop processing of the main circuit 25 of the power converter 1 when the brake 7 is normal is performed. First, similarly to the operation of the flowchart of the first landing operation in FIG. 3, the car 4 is driven by the motor 2 to drive to the landing position of the target floor (step 31), and the car 4 is in the landing position. When arriving at, the brake 7 is closed and the car 4 is held (step 32). Next, the speed command value is set to zero and the power converter is continuously operated to open the door (step 33). Next, the conditional branch 34 compares the torque command value output from the speed control system 21 with a predetermined reference value. That is, the torque command value is small when the brake 7 is operating normally, but the torque command value is large when there is an abnormality in the brake 7 and it is necessary to stop the car with the torque from the electric motor. Become. Therefore, by providing a reference value at the intermediate point, if the torque command value is equal to or less than the reference value, it can be determined that the brake 7 is normal, and the main circuit of the power converter is stopped (step 35). As a result, the drive time of the power converter 1 can be reduced, which is effective for reducing the amount of electricity used and suppressing fatigue deterioration of the main circuit 25.

  If the torque command value is equal to or greater than the reference value in the conditional branch 34, it is determined that there is an abnormality in the brake 7, and the car 4 is announced with an announcement or a buzzer while holding the car in a state where torque is applied electrically. The passengers are urged to get off (step 36). A weight sensor for detecting the loaded weight is attached to the car 2. When it is confirmed that there are no passengers in the car (step 37), the motor 2 is driven by the power converter 1 to drive the car. Is moved to the vicinity of the top floor (step 38). Then, the speed is reduced near the top floor, and the car (or the counterweight near the bottom floor) is made to collide with the shock absorber at a very low speed beyond the top floor landing position (step 39). Is stopped (step 40). Further, in step 41, a notification is issued to the monitoring center.

  The reason for moving the car to the vicinity of the top floor in step 38 is as follows. Under the condition that there is no braking by the brake 7 and the power converter 1 is stopped when the passenger is not in the car, the car 4 is pulled up by the counterweight and lifts. For this reason, it is based on the intention to safely move the car to the vicinity of the top floor by electrical control in advance. The reason why the bumper collides with the shock absorber at step 39 is as follows. If the car 4 is kept stationary for a long time, power is consumed and a heat load is concentrated on a specific semiconductor switch among the semiconductor switches constituting the power converter main circuit 25. May cause damage. For this reason, it is possible to suppress power consumption by colliding with the shock absorber at an extremely low speed at which damage does not occur and stopping the power converter, and it is possible to suppress the spread of further adverse effects such as breakage of the semiconductor switch. If the power converter 1 is stopped in this state, the car is stopped at the top (as described above, the car is not lowered because it is pulled by the counterweight). In addition, even when the state in which the car is kept electrically stationary is maintained for a long time, it is possible to prevent concentration of heat load on the specific switch by moving the car 4 up and down by a small amount.

FIG. 7 is a block diagram of the third landing operation of FIG. The controller 8 in this case includes a torque command magnitude comparison unit 42, a converter stop unit 43, and an emergency control mode drive unit 44 in addition to the brake drive processing unit 18, the power converter control calculation unit 19 and the door drive unit 20 of FIG. Consists of. The comparison between the torque command value and the reference value in the conditional branch 34 in FIG. 6 is performed by the torque command magnitude comparison unit 42. If it is determined that the brake 7 is normal, the converter stop unit 43 causes the PWM calculation unit to A command to turn off the output of 23 is issued to stop the operation of the main circuit 25 of the power converter. When the torque command magnitude comparison unit 42 determines that the brake 7 is abnormal, the torque command magnitude comparison unit 42 switches to the emergency control mode drive unit 44 to electrically stop the car with the speed command value of zero, and Implement warnings. Further, after the passenger gets off, the car is guided to the top floor in response to a command from the emergency control mode drive unit 44, and the power converter is stopped after reporting to the monitoring center.

FIG. 8 is a flowchart of the fourth landing operation of the first embodiment of FIG. The fourth landing operation is another example in which the stop process of the main circuit 25 of the power converter 1 is performed when the brake 7 is normal as in the fourth landing operation. First, similarly to the operation of the flow chart of the first landing operation in FIG. 3, the car 4 is driven by the motor 2 to drive to the landing position of the target floor (step 45). When arriving at, the brake 7 is closed and the car 4 is held (step 46). Next, the speed command value is set to zero and the power converter is continuously operated to open the door (step 47). Next, the torque command value output from the speed control system 21 is compared with a value calculated from a past history value (step 48). That is, when there is an abnormality in the brake 7, the torque command value is larger than the past history value. For this reason, when it is greatly different from the past history value, it is determined that the brake 7 is abnormal. This has the effect of improving the accuracy of abnormality determination.

In the conditional branch of step 48, if the current torque command value is almost equal to the history value and the brake is determined to be normal, the torque command value is left in the history (step 49), and the main circuit of the power converter is stopped. (Step 50). The degree of progress of brake deterioration may be determined from the history of torque command values acquired in step 49, and a warning may be issued to the monitoring center when it is determined that there is no problem in operation, but brake replacement is desirable. If it is determined in step 48 that there is an abnormality in the brake 7, the passenger is prompted to get off while holding the car in the state of being electrically torqued as in the third landing operation (step 51) When it is confirmed that there are no passengers in the car (step 52), the car is moved to the vicinity of the top floor (step 53). Then, the car is caused to collide with the shock absorber at a very low speed (step 54), the power converter 1 is stopped (step 55), and a notification is issued to the monitoring center (step 56).

FIG. 9 is a block diagram of the fourth landing operation of FIG. The controller 8 in this case is in addition to the brake drive processing unit 18, the power converter control calculation unit 19, the door drive unit 20, the torque command magnitude comparison unit 42, the converter stop unit 43, and the emergency control mode drive unit 44 of FIG. The torque command history acquisition unit 57 is configured. In step 48 of FIG. 8, the torque command value and the value calculated from the past history value obtained from the torque command history acquisition unit 57 are compared by the torque command magnitude comparison unit 42, and there is no abnormality in the brake 7. If it is determined, the converter stop unit 43 issues a command to turn off the output of the PWM calculation unit 23 to stop the operation of the main circuit 25 of the power converter. When the torque command magnitude comparison unit 42 determines that the brake 7 is abnormal, the torque command size comparison unit 42 switches to the emergency control mode drive unit 44 to electrically stop the car with the speed command value zero, and Implement warnings. Further, after the passenger gets off, the car is guided to the top floor in response to a command from the emergency control mode drive unit 44, and the power converter is stopped after reporting to the monitoring center.

  In the third landing operation and the fourth landing operation, the torque command value is compared with a specified value or a history value. However, a torque current value having a relationship proportional to the torque command value may be used.

  Further, the failure or abnormality of the brake 7 described in the first embodiment is not limited to the failure or abnormality of the brake 7 body, but the brake 7 may not operate normally due to the failure or abnormality of the braking system such as the brake circuit 9. Including.

  FIG. 10 shows an elevator system according to a second embodiment of the present invention. At least the power converter 1, the motor 2 driven by the power converter 1, the sheave 3 that rotates with the operation of the motor 2, and the sheave 3 are hung. A car 4 that is connected to a rope and moves up and down as the sheave 3 rotates, a counterweight 5, a rotary encoder 6 that is attached to the motor 2 and detects the rotation of the motor shaft, and a motor that is used when passengers get on and off. 2, the brake 7 that holds the car 4, the controller 8 that generates control signals for raising and lowering the car 4 and driving the brakes 7, the brake circuit 9 that drives the brakes 7 from the control signals of the controller 8, and the car 4 Governor pulley 58 that is part of the governor system used to detect speed abnormalities in the vehicle, governor encoder 59 attached to the governor pulley 58, and raising / lowering of the car 4 Position detector 60 installed in the car 4 ride for accurate locating in and constitute a shielding plate 61 installed on the wall surface of the building side to cause the locating the position detector 60.

  The governor system is a device in which a governor rope is hung on a governor pulley 58 installed in the upper part of the hoistway and a tension car installed in the lower part of the hoistway separately from the main rope suspended from the sheave 3, and the speed of the car 4 Used for anomaly detection. Since the governor rope is not intended to suspend heavy objects like the main rope, the governor pulley 58 can be rotated with extremely small expansion and contraction and pulling force. For this reason, by attaching the governor encoder 59 to the governor pulley 58 and reading the position, an accurate position of the car can be grasped. In general, when an elevator is landing, the position of a car is estimated by using information of a rotary encoder 6 attached to the motor 2, and a shielding plate 61 installed on a wall surface on the building side is used as a position detector 60. The controller 8 grasps the position of the car 4 by repeatedly correcting the estimated value every time the vehicle passes. Then, the vehicle is stopped at the landing position and the brake 7 is driven. In the second embodiment, an abnormality including a brake is detected by detecting the exact landing position and detecting and grasping the landing error while detecting the exact position of the car obtained from the governor encoder 59 in a state where it is stopped by the normal landing operation. Implement signs detection.

FIG. 11 is a flowchart of the first landing error generation process in the second embodiment. Similarly to the operation at the time of landing of the car in FIG. 2, the car 4 is driven by the motor 2 to drive to the landing position of the target floor (step 62), and the brake 7 is driven upon arrival at the landing position, And the car 4 is hold | maintained, operating the power converter 1 by speed command value zero similarly to Example 1 (step 63). In this case, the position (landing error) of the car obtained from the governor encoder 59 is detected (step 64). Here, the timing for detecting the position of the car is preferably a period from when the brake 7 is driven to when the car door is opened. That is, when the passenger gets on and off, the car may vibrate and the detected value of the car position may not be stable, and there is an effect that accurate information can be acquired by detecting before the passenger gets on and off. Next, it is determined by the conditional branch 65 whether or not the acquired value is larger than a reference value of a predetermined landing error. If the acquired value is smaller than the reference value, the abnormal sign detection process is terminated. If the acquired value is larger than the reference value, a notification is sent to the monitoring center (step 66). Here, the reference value may be a value smaller than that which hinders the operation, and may be reported to the monitoring center as a predictive phenomenon grasp. Further, when the landing error amount is remarkably larger than the reference value, the elevator operation may be stopped after reporting to the monitoring center.

  FIG. 12 is a block diagram of the first landing error generation process of FIG. In this case, the controller 8 includes a landing error magnitude comparison unit 67 in addition to the brake drive processing unit 18, the power converter control calculation unit 19, and the door drive unit 20. The comparison between the acquired car position information value in the conditional branch 65 of FIG. 11 and a predetermined reference value is performed by the landing error magnitude comparison unit 67, and if there is an abnormality with respect to the landing position that is larger than the reference value. If it is determined, a notification is sent to the monitoring center 11.

FIG. 13 is a flowchart of the second landing error generation process in the second embodiment. This method, unlike FIG. 11, keeps past history information of the position of the car (landing error). First, similarly to the first landing error occurrence processing in FIG. 11, the car 4 is driven by the motor 2 to drive to the landing position on the target floor (step 68), and upon arrival at the landing position. The brake 7 is driven, the car 4 is held (step 69), and the position (landing error) of the car obtained from the governor encoder 59 is detected (step 70). Next, the car position detected in step 70 is compared with the position information of the past history, and it is determined whether or not the car position has changed more than the past history (step 71). If the change from the past history is not large, the car position detected in step 70 is written as history information (step 72), and the abnormality sign detection process is terminated. If there is a large change from the past history, a warning is issued to the monitoring center (step 73), the car position detected in step 70 is written as history information (step 74), and the abnormal sign detection process is terminated.

FIG. 14 is a block diagram of the second landing error generation process of FIG. The controller 8 in this case is configured by a landing error history acquisition unit 75 in addition to the brake drive processing unit 18, the power converter control calculation unit 19, the door drive unit 20, and the landing error magnitude comparison unit 67 of FIG. 13. . In the conditional branching of step 71 in FIG. 13, the comparison between the car position information acquired in step 70 and the past history value obtained from the landing error history acquisition unit 75 is performed by the landing error magnitude comparison unit 67. If it is determined that there is, the monitoring center 11 is notified.

  FIG. 15 is an example of car position (landing error) history information in the second landing error occurrence process. In FIG. 15, an average value of past histories is derived, and the average value is compared with the car position detected in step 70. Thereby, the case where the landing error occurs due to the installation accuracy problem of the shielding plate 61 and the case where the abnormality occurs can be separated. In addition, by periodically transmitting history information to the monitoring center, there is another effect that even if a landing error occurs due to the installation accuracy of the shielding plate 61, it can be corrected in a maintenance manner. . Further, FIG. 15 shows an example in which only the landing error information acquired this time has greatly changed with respect to the past history. The form to report may be sufficient.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the technical idea.

It is a block diagram which shows the 1st Example of this invention. It is a flowchart of the operation | movement at the time of the conventional car landing. It is a flowchart of the 1st landing operation | movement of the 1st Example of this invention. It is a block diagram of the first landing operation. It is a flowchart of the 2nd landing operation | movement of the 1st Example of this invention. It is a flowchart of the 3rd landing operation | movement of the 1st Example of this invention. It is a block diagram of the 3rd landing operation. It is a flowchart of the 4th landing operation | movement of the 1st Example of this invention. It is a block diagram of the 4th landing operation. It is a block diagram which shows the 2nd Example of this invention. It is a flowchart of the process at the time of the 1st landing error generation | occurrence | production of 2nd Example. It is a block diagram of the processing at the time of the first landing error occurrence. It is a flowchart of the process at the time of the 2nd landing error generation | occurrence | production of 2nd Example. It is a block diagram of the processing at the time of the 2nd landing error generation. It is an example of car position history information.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Power converter 2 Motor 3 Sheave 4 Car 5 Balance weight 6 Rotary encoder 7 Brake 8 Controller 9 Brake circuit 10 Power supply 11 Monitoring center 18 Brake drive processing part 19 Power converter control calculating part 20 Door drive part 21 Speed control System 22 Current control system 23 PWM calculation unit 24 Drive circuit 25 Power converter main circuit 42 Torque command magnitude comparison unit 43 Converter stop unit 44 Emergency control mode drive unit 57 Torque command history acquisition unit 58 Governor pulley 59 Governor encoder 60 Position detector 61 Shielding plate 67 Landing error size comparison unit 75 Landing error history acquisition unit

Claims (16)

A power converter, a motor driven by the power converter, a sheave that rotates in accordance with the operation of the motor, and a lift that is connected to a rope that is hung on the sheave and that moves up and down as the sheave rotates. An elevator system comprising: a car and a counterweight, a brake that stops the motor and holds the car, and a controller that generates control signals for raising and lowering the car and opening and closing the brake;
The controller is in a state in which the car is closed said brake stops at the landing zone, continues always to drive the power converter speed command value is zero in a state where the car door is open Rukoto Elevator system characterized by According to claim 1, wherein the controller is in a state of driving the power converter before Symbol speed command value zero, an elevator system, characterized in that gives a command to open the door of the car.   2. The elevator system according to claim 1, wherein the controller has a speed control system that operates in proportional control when the power converter is driven at the speed command value of zero.   The elevator system according to any one of claims 1 to 3, wherein a main circuit of the power converter is stopped when an elevator call is not generated for a predetermined time.   The elevator system according to any one of claims 1 to 3, wherein the main circuit of the power converter is stopped when a torque command value to be generated by the motor is equal to or less than a predetermined reference value.   The main circuit of the power converter according to any one of claims 1 to 3, wherein a history value of a torque command value to be generated by the motor is acquired and the history value and a current torque command value are substantially equal. An elevator system characterized by stopping the vehicle.   6. The elevator system according to claim 5, further comprising means for prompting passengers in the car to get off when the torque command value is larger than the reference value.   7. The elevator system according to claim 6, further comprising means for prompting passengers in the car to get off when the current torque command value is different from the history value.   6. The elevator system according to claim 5, wherein when the torque command value is larger than the reference value, the car is moved to a position above the top floor landing position and stopped.   The elevator system according to claim 6, wherein when the current torque command value is different from the history value, the car is moved to a position higher than the top floor landing position and stopped.   6. The elevator system according to claim 5, wherein a warning is issued to a monitoring center when the torque command value is larger than the reference value.   The elevator system according to claim 6, wherein a warning is issued to a monitoring center when the current torque command value is different from the history value. In any one of claims 1 to 3, possess the governor pulley is part of the governor system which uses speed abnormality detection of the car, and the governor encoder mounted on the governor pulley, and,
The controller drives the car by the motor to drive to the landing position of the target floor, drives the brake when arriving at the landing position, holds the car, and is obtained from the governor encoder. An elevator system comprising means for detecting a position of a car or a landing error.   14. The elevator system according to claim 13, wherein the timing of detecting the position of the car or the landing error by the governor encoder is a period from when the brake is driven to when the door of the car is opened.   14. The elevator system according to claim 13, further comprising means for leaving the position of the car or the landing error acquired by the governor encoder as history information.   14. The difference amount between the position of the car or the landing error acquired by the governor encoder and a predetermined amount or an average value obtained from a past history is larger than a predetermined size. An elevator system characterized by having means for reporting to a monitoring center when it is large.

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