JP4850708B2 - Elevator control system - Google Patents

Description

  The present invention relates to an elevator control system in which a single car is driven by two (or more) hoisting machines.

  In a machine room-less elevator or the like, a hoisting machine is installed between a car moving space and a hoistway wall, so that the hoisting machine is required to be downsized. For example, a hoisting machine is arranged in a pit at the lower part of the hoistway, and a hoisting machine is arranged in a gap between the hoistway side wall and the cage.

  However, a large-capacity elevator has a problem that the size of the hoistway becomes large due to the installation of the hoisting machine because there is a limit to downsizing because the output of the motor is large. Therefore, an elevator that can install the hoisting machine in the space between the moving space of the car and the hoistway wall by using two hoisting machines that drive the car and reducing the required torque per car is proposed. Has been.

  When a car is driven by hoisting a rope with such an elevator, it is necessary to equalize the tension of the ropes applied to the two hoisting machines. Is not achieved.

  That is, in such an elevator control system, two drive control systems comprising a hoisting machine and a driving device are arranged, and the rotational speed of each hoisting machine follows the command based on the speed command from the operation management unit. (See, for example, Patent Document 1).

However, in the conventional elevator control system described above, the car is normally driven and controlled while the tensions of the two ropes are balanced. If there is a difference in speed, the rope tension will be higher when the rope speed is higher when climbing. Conversely, when descending, the rope tension with the slower rope speed increases. As described above, when the difference in rope tension occurs, not only the riding comfort is deteriorated, but also an adverse effect on the equipment is caused by the distortion of the car and the excessive load on the rail. In addition, since the load is biased to one of the motors, there is a problem that the driving ability is reduced.
Japanese Examined Patent Publication No. 7-42063 (FIG. 5)

  The present invention has been made in order to solve the problems associated with the above-described conventional example. In an elevator control system in which one car is driven by two (or more) hoisting machines, two elevators are used. An object of the present invention is to provide an elevator control system capable of speed control while balancing the rope tension applied to the hoisting machine.

The elevator control device according to the present invention includes two hoisting machines, two ropes suspended from the two hoisting machines, and a two-point suspension structure suspended from one end of the two ropes. Tension detection for detecting the rope tension of each of the two ropes in an elevator control system comprising a counterweight suspended from the other end of the two ropes and a drive control device for driving the two hoisting machines And a compensator for controlling the rotational speed of the hoist to balance the rope tension by outputting a feedback control signal to the drive control device in accordance with the tension difference between the two ropes detected by the tension detector. The compensator includes at least one of a compensation element that sends a compensation amount of a speed command gain according to a tension difference between two ropes detected by the tension detector, and a gain of the compensation element is reduced. By gain correction towards the hoisting machine, the difference between the torque command value of the two hoist not corrected speed command gain by reducing the gain of the compensation elements is smaller than a predetermined value Thus, a dynamic compensation calculation unit that is insensitive to an uneven load based on a torque difference, and an abnormality detection unit that determines that an abnormality occurs when the compensation amount from the compensation element is greater than a predetermined value and sends an emergency stop command. The drive control device compensates to lower the rotational speed of the hoisting machine with a high rotational speed so as to fit the hoisting machine with a low rotational speed according to the tension difference between the two ropes detected by the tension detector. A feedback control signal is output .

  According to the present invention, in an elevator control system in which one car is driven by two hoisting machines, the speed can be controlled while balancing the rope tension applied to the two hoisting machines.

1 is a block diagram showing an overall configuration of an elevator control system according to the present invention. It is a block diagram which shows the internal structure of the compensator shown in FIG.

Hereinafter, the present invention will be described based on the illustrated embodiments.
Embodiment 1 FIG.
1 is a block diagram showing a configuration of an elevator control system according to Embodiment 1 of the present invention. As shown in FIG. 1, the elevator control system according to the present invention includes two hoisting machines 4a and 4b including hoisting motors 1a and 1b, brakes 2a and 2b, and sheaves 3a and 3b. Ropes 5a and 5b are respectively suspended on the cars 3a and 3b. One ends of the ropes 5a and 5b are engaged with the car 6 via springs 8a and 8b, and the other ends are connected to counterweights 7a and 7b, respectively. The rotational speeds of the hoisting machines 4a and 4b are detected by speed detectors 9a and 9b, respectively, and the tensions of the ropes 5a and 5b are detected by load detectors 10a and 10b, respectively.

  Here, the load detectors 10a and 10b function as a scale device that detects the load in the car by measuring the spring displacement that expands and contracts as the load increases or decreases as passengers get in and out of the car 6, and the spring displacement is Since it is proportional to the rope tension in principle, the rope tension is measured and it also functions as a tension detector.

  The hoisting motors 1 a and 1 b are driven and controlled by a drive control device 11. The drive control device 11 compares the speed command from the operation management unit 12 that determines the traveling pattern of the car 6 and sends out a speed command, the speed command from the operation management unit 12, and the speed detection value by the speed detectors 9a and 9b, The speed control units 13a and 13b that respectively calculate the torques to be output by the two hoisting motors 1a and 1b and send torque commands, and the hoisting motors 1a and 1b according to the torque commands from the speed control units 13a and 13b. Torque control units 14a and 14b that send commands to control the generated torque, and power converters 15a and 15b that control the power supplied to the hoisting motors 1a and 1b in accordance with commands from the torque control units 14a and 14b. It consists of.

  Furthermore, the elevator control system of the present invention outputs a feedback control signal to the drive control device 11 in accordance with the tension difference between the two ropes detected by the load detectors 10a and 10b as tension detectors. A compensator 16 is provided for controlling the rotational speeds of the hoisting motors 1a and 1b to balance the tension. The compensator 16 controls the rotational speed of at least one hoisting machine only when the tension difference between the two ropes detected by the load detectors 10a and 10b serving as tension detectors exceeds a predetermined value. Accordingly, a feedback control signal is output to the drive control device 11 so that the speed of the hoisting motor having the higher rotational speed is lowered by the difference in the rope tension and adjusted to the lower one.

  FIG. 2 is a block diagram showing an internal configuration of the compensator 16. As shown in FIG. 2, the compensator 16 compensates for a gain K17 corresponding to a speed command sent from the operation management unit 12 to the speed control unit 13 (generally 13a and 13b). A compensation element 18 for sending a compensation amount of the gain K according to the tension difference between the two ropes detected by the load detectors 10a and 10b, speed detection values from the speed detectors 9a and 9b, and speed control units 13a and 13b. Is selected on the basis of the torque command from the lower speed, and the compensation amount of the gain K of the compensation element 18 is reduced to correct the gain of the higher speed hoisting machine. The speed of the upper machine, that is, the rope tension is matched, and the difference between the torque command values output from the speed controllers 13a and 13b based on the speed difference or speed feedback between the two hoisting machines is predetermined. If smaller, the gain of the compensation element 18 is reduced and the gain K is not corrected, thereby making the dynamic compensation calculation unit 19 insensitive to the torque difference, that is, the eccentric load, and the compensation amount from the compensation element 18. And an abnormality detection unit 20 that determines that an abnormality occurs when the value is larger than a predetermined value and sends an emergency stop command.

  Next, the operation | movement which concerns on the control system of an elevator provided with the structure shown in FIG.1 and FIG.2 is demonstrated. When a call button (not shown) on the platform or the car 6 is pressed, the operation management unit 12 determines the traveling pattern of the car 6 and outputs a speed command to the speed control unit 13.

  The speed control unit 13 compares the speed command from the operation management unit 12 with the rotational speeds of the two hoisting machines 4a and 4b (the hoisting motors 1a and 1b) detected by the speed detectors 9a and 9b. Torques to be output by the two hoisting motors 1a and 1b are respectively calculated, and torque commands are sent to the torque control units 14a and 14b. The torque control units 14a and 14b operate the power converters 15a and 15b according to the respective torque commands to control the torque generated by the motors 1a and 1b.

  By the operation of the drive control device 11 described above, the rotational speeds of the hoisting motors 1a and 1b and the sheaves 3a and 3b are controlled by a predetermined speed pattern, the ropes 5a and 5b are traction driven, and the car 6 is moved to the destination floor. Carry.

  Further, when the car 6 arrives at the destination floor, the brakes 2a and 2b are operated to stop the rotation of the sheaves 3a and 3b, and the power supply to the hoisting motors 1a and 1b is cut off to complete a series of operations.

  The springs 8a and 8b are for preventing vibration propagation from the ropes 3a and 3b to the car 6 and ensuring a comfortable ride for passengers. The springs 8a and 8b expand and contract when a person in the car 6 gets on and off and the load increases or decreases. Therefore, the load in the car can be detected by measuring the displacement of the spring. Since this spring displacement is proportional to the rope tension in principle, the rope tension is measured. The load detectors 10a and 10b apply this principle, for example, and detect the tension of the ropes 3a and 3b, respectively. There are other methods for detecting the rope tension, and the invention described here does not depend on the detection method.

  In the elevator control system of the present invention, the drive controller 11 controls the rotational speed of at least one hoisting machine only when the tension difference between the two ropes exceeds a predetermined value by the compensator 16. A feedback control signal is output to the motor, and the speed of the hoisting motor having the higher rotational speed is lowered by the difference in the rope tension so as to adjust to the lower one.

  That is, the compensation element 18 operates so as to send a compensation amount of the gain K with respect to the speed command sent from the operation management unit 12 to the speed control unit 13 (generically 13a and 13b) according to the tension difference between the two ropes. Then, based on the speed detection values from the speed detectors 9a and 9b and the torque command from the speed control units 13a and 13b, the dynamic compensation calculation unit 19 selects a hoisting machine having a low speed as a reference, and a compensation element By reducing the compensation amount of the gain K and gain correction for the higher speed hoisting machine, the speeds of the hoisting machines, that is, the rope tensions are made to coincide with each other.

  Therefore, according to the above-described embodiment, since the rope tension is controlled to be balanced, there is no problem that the car is biased and driven by one hoisting machine. That is, the speed can be controlled while balancing the rope tension applied to the two hoisting machines.

  In addition, since the load detectors 10a and 10b serving as the weighing devices for detecting the load in the car also serve as the tension detector, it can be configured at a low cost. It is possible to check for malfunctions when the scale is detected.

  In addition, since the feedback control is performed in the direction where the rope tension is lower, the safe side can be designed by compensating for the speed decreasing.

Furthermore, since feedback is performed only when the difference in rope tension exceeds a predetermined value, malfunction can be prevented by making insensitive to the eccentric load and avoiding unnecessary compensation.

Claims (3)

Two hoisting machines,
Two ropes suspended on two hoisting machines,
A two-point suspended structure suspended from one end of two ropes,
A counterweight suspended from the other end of the two ropes;
In an elevator control system comprising a drive control device for driving two hoisting machines,
A tension detector for detecting the rope tension of each of the two ropes;
A compensator for controlling the rotational speed of the hoist to output a feedback control signal to the drive control device in accordance with the tension difference between the two ropes detected by the tension detector to balance the rope tension;
The compensator is
A compensation element for sending a compensation amount of a speed command gain according to a tension difference between the two ropes detected by the tension detector;
By reducing the gain of the compensation element, by gain correction towards the at least one one of the hoisting machine, when the difference between the torque command value of the two hoist is smaller than the predetermined value the A dynamic compensation computing unit that makes the compensation element insensitive by reducing the gain of the compensation element and not correcting the speed command gain;
An abnormality detection unit that determines an abnormality when a compensation amount from the compensation element is larger than a predetermined value and sends an emergency stop command ;
Feedback to the drive control device so as to compensate to reduce the rotational speed of the hoisting machine having a high rotational speed so as to fit the hoisting machine having a low rotational speed in accordance with the tension difference between the two ropes detected by the tension detector. An elevator control system that outputs a control signal . The elevator control system according to claim 1.
The tension control system also serves as a scale device that detects a load in the car . The elevator control system according to claim 1 or 2 ,
The compensator feedback-controls the drive control device to control the rotational speed of at least one hoisting machine only when the tension difference between the two ropes detected by the tension detector exceeds a predetermined value. An elevator control system characterized by outputting a signal.

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