JP3359658B2 - Elevator control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an elevator control device, and more particularly to an elevator control device capable of smoothly starting an elevator.

[0002]

2. Description of the Related Art FIG. 4 is a block diagram showing a conventional elevator control device. In FIG. 4, 1 is a motor, 2 is a hoist driven by the motor 1, 3 is a main rope wound around a sheave (not shown) of the hoist 2, and 4 is attached to one end of the main rope 3. The elevator car 5 is a counterweight attached to the other end of the main rope 3. Reference numeral 6 denotes a speed detector provided on the rotating shaft of the motor for detecting the rotation speed of the motor and outputting it as a feedback speed signal 6a. Reference numeral 7 denotes a load provided in the car 4, and the load in the car 4 (for example, the weight of the passenger). ), And a weighing device 8 that outputs the load signal 7a.
A power converter 9 for supplying power for driving the motor, and a current detector 9 provided between the power converter 8 and the motor 1 for detecting a motor current and outputting it as a current signal 9a. Further, 10 is a speed command generator for generating a speed command signal 10a of the elevator, 11 is connected to the output side of the speed command generator 10 and the output of the speed detector 6, and based on the speed command signal 10a and the feedback speed signal 6a, This is a speed control device that generates one torque command signal 11a. 12 is a weighing device 7
Calculates the unbalance load of the car 4 and the counterweight 5 from the load signal 7a of the car 4 which is the output of the weighing device 7 and outputs the torque compensation signal 12a based on the unbalance load. The compensating device 13 is connected to the output side of the speed control device 11 and the scale compensating device 12,
An adder 14 for adding a torque compensation signal 12a to the torque compensation signal 11a to obtain a second torque command signal 11b ; an adder 14 is connected to the output side of the speed detector 6, the current detector 9 and the adder 13; Command signal 11b, feedback speed signal 6a
And the input signal 14 to the power converter 8 by the current signal 9a
a is a torque control device.

[0003] Next, the operation of the conventional elevator control device configured as described above will be described. When a passenger enters the car 4, the load on the car 4 is detected by the weighing device 7, and the torque compensation signal 12 a is calculated by the weighing compensation device 12. The torque compensation signal 12a corresponds to a motor torque for balancing the unbalance load between the car 4 and the counterweight 5 side. After the elevator starts, the speed command signal 1
The first torque command signal 11a is output from the speed control device 11 based on 0a and the feedback speed signal 6a. Normally, the speed control is calculated by the speed command signal 10a and the feedback speed signal 6a.
PI calculation based on the deviation of. The first torque command signal 11a is added to the torque compensation signal 12a by the adder 13 to form a second torque command signal 11b. The second torque command signal 11b is input to the torque control device 14, and the power converter 8 drives the motor 1 based on the output signal 14a of the torque control device 14, and the car 4 is moved up and down.

[0004]

Since the conventional elevator control device is configured as described above, it has the following problems. Generally, in order for a stationary object to start moving, an external force is required to overcome the maximum static friction force. This maximum static friction force is much larger than the dynamic friction force when the object is moving. When starting an elevator equipped with a speed reducer, a large static friction force acts on each part such as a gear (not shown) of the speed reducer, so that a large starting torque is required. However, immediately after the start, a dynamic friction force smaller than the start torque acts, so that the elevator is driven with an excessive torque, and the speed control device attempts to compensate for this, causing large vibration.

This will be described with reference to FIG. Before the start of the elevator, the second torque command signal 11b includes the signal shown in FIG.
As shown in (1), a torque for compensating the unbalance load is given in advance. When the elevator starts, Figure 5
As shown in (a), when the speed command signal 10a rises and the deviation from the feedback speed signal 6a increases, and when the second torque command signal 11b becomes a value that can overcome the static friction force by PI calculation, The elevator starts moving.
However, as described above, immediately after the start, the elevator is excessively driven because it is driven with an excessive torque. For this reason, the torque command signal 11b is rapidly reduced by the speed control device 11, and a large vibration is generated in the acceleration signal of the car 4 as shown in FIG. Such a vibration can be suppressed if the response of the speed control system is sufficiently fast, but the response of the control system cannot be made fast with a normal elevator.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and has as its object to provide an elevator control apparatus that suppresses vibration at the time of starting due to static friction.

[0007]

Means for Solving the Problems] elevator control apparatus according to the present invention, the torque system of controlling the speed of the elevator by driving a motor by inputting the torque command signal
And control device, the start detecting means before Symbol elevator detects an activation period from when you start to reach a predetermined speed, is connected to the launch detection hand stage, the activation a dither signal having a predetermined amplitude and frequency An oscillator that outputs the signal over a period, and the dither signal output by the oscillator is added to the torque command signal.
In addition, the load of the elevator is provided in the elevator to detect the load.
Further comprising a load detecting unit that outputs
Amplitude or frequency according to the load detected by the load detection means
Output a dither signal having a number over the activation period.
It is.

[0008]

The elevator control device according to the present invention operates as follows. The dither signal added to the torque command signal when the elevator starts up causes the motor to vibrate according to its frequency and amplitude. Due to the vibration of the motor, the gears of the speed reducer also vibrate, and the static friction force is changed to the dynamic friction force, so that a large starting torque is not required. Therefore, immediately after the start of the elevator, the drive torque does not greatly change and a smooth start can be performed.

[0009]

[Embodiment 1] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing an elevator control device according to the present invention. Reference numeral 15 denotes an activation detection device connected to the speed detector 6 and an activation switch (not shown) of the elevator. The activation detection device 15 detects an activation period from when the elevator is activated to when the elevator reaches a predetermined speed. Startup detection signal 1
A start detection device 16 for outputting 5a is connected to the weighing device 7 and the start detection device 15, and the load signal 7 is output over the start period.
dither signal a small sine wave of amplitude and frequency corresponding to a 16
An oscillator 17 generated as a is an adder that adds the dither signal 16a to the second torque command signal 11b and outputs the result to the torque control device 14 as the third torque command signal 11c. The motor 1 to the torque control device 14 are the same as those shown in FIG. The amplitude and frequency of the dither signal 16a are set so that even if the speed reducer (not shown) vibrates, the vibration is not transmitted to the car 4 due to the attenuation of the speed reducer and the rope 3 system. Also, in an elevator with a speed reducer, the characteristics of the motor driving torque with respect to the unbalance load of the load greatly differ between the power running and the regenerative.
2, the relationship between the unbalance load and the torque compensation signal 12a is set as shown in FIG. In FIG.
FLU is NL if the load is at the maximum when the elevator is raised
D indicates the case where the load is minimum when the elevator is lowered, FLD indicates the case where the load is maximum when the elevator is lowered, and NLU indicates the case where the load is minimum when the elevator is raised.

Next, the operation will be described with reference to FIGS.
3A is a diagram showing a speed command signal 10a and a feedback speed signal 6a at the time of starting, FIG. 3B is a diagram showing a third torque command signal 11c, and FIG. 3C is a diagram showing an acceleration signal of the car 4 respectively. . At the same time as the start-up, the start-up detection signal 15a
5 and the dither signal 16 a is output from the oscillator 16. A third input signal to the torque control device 14
The torque command signal 11c is formed by adding the dither signal 16a to the second torque command signal 11b by the adder 17. The motor 1 is slightly vibrated by the dither signal 16a, and the gear of the speed reducer (not shown) is generated by the vibration of the motor 1.
Also vibrate minutely. Even if the reducer vibrates, the reducer and low
Due to the damping of the pump system , no vibration is transmitted to the car 4. Therefore, even if the elevator is apparently stationary, the frictional force of the speed reducer is not a static frictional force but a dynamic frictional force. Therefore, a large driving torque is not required even when the speed command signal 10a rises and starts to move. The signal 6a follows the speed command signal 10a, and the elevator is started smoothly. When the elevator starts moving and reaches a predetermined speed, the start-up detection device 15 stops outputting the start-up detection signal 15a,
The oscillator 16 stops outputting the dither signal 16a. Therefore, after the elevator starts moving, the elevator is smoothly operated by the second torque command signal 11b.

As described above, in the embodiment of the present invention, the speed command generating device 10, the speed control device 11, the weighing device 7, the weighing compensating device 12, and the adder 13 constitute the torque command signal output means in claim 1, The second torque command signal 11b constitutes the torque command signal according to claim 1, the weighing device 7 constitutes load detection means according to claim 1, and the activation detection device 15 and the speed detector 6 comprise the activation detection means according to claim 1. Is composed. Although a small sine wave is used as the dither signal 16a in the embodiment, the present invention is not limited to such a sine wave, and may be a pulse wave or the like.

[0012]

As it is evident from the foregoing description, the elevator control device in accordance with the present invention, the torque system to perform elevator speed control by driving the motor by inputting the torque command signal
And control device, the start detecting means before Symbol elevator detects an activation period from when you start to reach a predetermined speed, is connected to the launch detection hand stage, the activation a dither signal having a predetermined amplitude and frequency and a oscillator that outputs over a period, start of the no increase in starting torque by the static friction force because the dither signal output is as Ru is added to the torque command signal by an oscillator, an elevator with a speed reducer Can be performed smoothly.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an elevator control device according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a relationship between an unbalanced load and a torque compensation signal.

FIG. 3 is a diagram showing signal waveforms at the time of startup according to the embodiment of the present invention.

FIG. 4 is a block diagram showing a conventional elevator control device.

FIG. 5 is a diagram showing signal waveforms at the time of startup by a conventional elevator control device.

[Explanation of symbols]

 Reference Signs List 1 motor 4 car 6 speed detector 7 weighing device 10 speed command generation device 11 speed control device 12 weighing compensation device 15 start detection device 16 oscillator 17 adder

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B66B 1/30 H02P 1/26 H02P 5/00

Claims (2)

(57) [Claims] 1. A torque control system for controlling a speed of an elevator by inputting a torque command signal and driving a motor.
And control device, the start detecting means before Symbol elevator detects an activation period from when you start to reach a predetermined speed, is connected to the launch detection hand stage, the activation a dither signal having a predetermined amplitude and frequency An oscillator that outputs the signal over a period of time, wherein the dither signal output by the oscillator is added to the torque command signal. (2)The elevator is provided in the elevator
Further comprising a load detecting means for detecting a load, The oscillator responds to a load detected by the load detecting means.
A dither signal having an amplitude or frequency
Output in between The method according to claim 1, wherein
The elevator control device.