JPH0768019B2 - Elevator speed controller - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speed controller for automatically adjusting a gain of a speed controller of a control system in an electric motor.

[0002]

2. Description of the Related Art Generally, the amount of GD ² (the amount corresponding to the moment of inertia) that changes depending on the type of motor or the fluctuation of the load.
It is desirable to optimally set the proportional gain of the speed adjuster according to the above, but for example, for gain adjustment of the elevator speed control system, the operator can see the response waveforms of the electric current and voltage of the electric motor on the site with a synchroscope. Was adjusting.

[0003]

For this reason, it has been a difficult work which requires time and skill. Also, Japanese Examined Sho 48
As disclosed in Japanese Patent No. 15838, a speed control system in operation is shifted to a stable limit by a special signal, parameters of the control system are estimated from behavior of the system in an unstable state, and parameters of a regulator (proportional gain) Although a method of automatically correcting the above has been proposed, it seems that it cannot be used for an elevator control system because it makes the control system into a periodically unstable state.

The present invention has been made in view of the above points,
An object of the present invention is to provide a speed control device in which adjustment work is automatically performed.

[0005]

The ideal speed command signal of the elevator, the speed signal of the elevator car, and the differential signal of the elevator car speed signal are matched, and the speed of the electric motor is controlled by the speed adjusting means having a proportional-integral element. In the controlled system, the torque command value t _q during constant acceleration of the elevator
The first computing means for computing the moment of inertia J based on ^* and the second computing means for computing the proportional gain K _SR of the speed adjusting means based on the moment of inertia J are provided, and the second computing means A setting means for resetting the obtained proportional gain K _SR in the speed adjusting means is provided.

[0006]

With the above construction, the proportional gain of the speed controller is automatically set to the optimum value when the elevator is operated for adjustment.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. 1 is a flow chart showing an embodiment of the present invention, FIG. 2 is an overall configuration diagram of an elevator speed control device to which the present invention is applied, and FIG. 3 is a block diagram shown in FIG.
In FIG. 2, 1 is a three-phase alternating current power supply, 2 is a converter for converting three-phase alternating current into direct current, 3 is a capacitor for smoothing direct current, 4 is PWM modulation of direct current, and is converted into three-phase alternating current of variable voltage / variable frequency. Inverter device, 5 is a three-phase induction motor for car hoisting (hereinafter simply referred to as an induction motor), 6 is a sheave driven by the induction motor 5, 7 is an elevator car, 8 is a counterweight, 9 is a car 7 And the main rope connecting the counterweight 8

Reference numeral 10 is a speed command device for commanding an ideal traveling speed of the elevator, 11 is a control device composed of a microcomputer for controlling the output voltage and frequency of the inverter device 4, and this is a speed command device. 1
The speed command signal 10a from 0 and the speed signal ω _r from the pulse encoder 12 that detects the rotation speed of the induction motor 5
Has been entered.

After the three-phase alternating current is rectified by the converter 2 and converted into direct current, the speed command device 10 operates when a car start command is issued while being smoothed by the capacitor 3 and being supplied to the inverter device 4. Then, the speed command signal 10a is given to the control device 11. As a result, the control system of the block diagram shown in FIG. 3 operates and the inverter device 4 operates to convert the smoothed direct current into the three-phase alternating current of the variable voltage / variable frequency shown in FIG. 2 (B). The alternating current is supplied to the induction motor 5 so that the induction motor 5 rotates and the cage 7 runs.

In FIG. 3, K _SR is a proportional gain of the speed controller ASR, T is a PI time constant of the speed controller ASR, K _t is a converted value of torque command t _q ^* / generated torque t _q , which is calculated from the torque command. The delay until the actual torque is generated is sufficiently faster than the ASR response, so it is ignored. J is the moment of inertia by the motor shaft conversion of the elevator mechanical system (GD ^2/4), tau is a rate response time constant of the target, and improving the response by differential feedback to the input of (Equation 1).

[0011]

[Equation 1]

When the transfer function of this control system is arranged,
(However, Equation 3), and the proportional gain of the speed controller K _SR
The optimum value of is

[0013]

[Equation 2]

[0014]

[Equation 3]

[0015]

[Equation 4]

In Equation 4, the speed response time constant τ and the converted value K _t are constants determined at the time of designing the control system and are known values that do not depend on the load, and the moment of inertia J is an unknown value that greatly changes depending on the elevator specifications. If the moment J can be automatically measured, the controller 11 calculates the speed adjuster AS according to the equation (4).
It can be seen that the optimum proportional gain K _SR of R can be calculated.

For the automatic measurement of the moment of inertia J, the motor shaft angular acceleration during elevator acceleration is dω /
Assuming dt (known), the moment of inertia J can be automatically measured from the equation 5 by knowing the torque command value t _q ^* at the time of constant acceleration of the elevator.

[0018]

[Equation 5]

FIG. 1 shows such a calculation procedure as a diagram. That is, a constant determined in advance at the time of designing the control system is initialized, and the adjustment operation is started with a balanced load. However, in step 2, after measuring the torque command value t _q ^* during constant acceleration of the elevator car, In step 3, the inertia moment J shown in Formula 5 is calculated by the microcomputer built in the control device 11.

Next, the microcomputer also calculates the proportional gain K _SR of the speed regulator ASR shown in the equation 4 in step 4, and then, in step 5, calculates it in place of the preset gain. Reset the proportional gain K _SR .

In an actual elevator system, the torque command value t _q ^* is corrected in consideration of the unbalanced torque and the torque corresponding to the traveling loss, and the moment of inertia J is calculated from the equation 5 based on the corrected value. It is possible to obtain a better speed control by calculating the proportional gain K _SR of the speed adjuster ASR.

[0022]

As described above, according to the present invention, since a series of calculations can be made into software when the optimum gain of the speed adjusting means is calculated by the microcomputer, it is very difficult to gain the gain. The adjustment work can be performed automatically and easily, which can significantly reduce the number of on-site man-hours and can significantly stabilize the elevator performance.

[0023]

[Brief description of drawings]

FIG. 1 is a flowchart showing an embodiment of the present invention.

FIG. 2 is an overall configuration diagram of an elevator speed control device to which the present invention is applied.

FIG. 3 is a block diagram of the device shown in FIG.

FIG. 4 is a claim correspondence diagram.

[Explanation of symbols]

10 speed command device 10a speed command signal 7 elevator car ω _r speed signal 5 three-phase induction motor 11 control device t _q ^* torque command value J inertia moment ASR speed controller K _SR proportional gain of speed controller ASR T speed controller ASR PI time constant

Claims (2)

[Claims] 1. An ideal speed command signal for an elevator, a speed signal for an elevator car, and a speed signal for the elevator car.
A first calculation for calculating a moment of inertia J based on a torque command value t _q ^* at the time of constant acceleration of an elevator, in a case where the speed of the electric motor is controlled by a speed adjusting means having a proportional- plus- integral element in association with a differential signal. means and, provided the second calculating means for calculating a proportional gain K _SR of the speed adjusting unit based on the moment of inertia J, the speed adjusting unit, the proportional gain K _SR obtained in said second arithmetic means An elevator speed control device comprising a setting means for resetting the speed. 2. The first calculation means is the mathematical expression 5 (where K is
_t is the converted value of torque command t _q ^* / generated torque t _q , dω
/ Dt is a means for calculating the inertia moment J by the motor shaft angular acceleration, and the second calculating means is a means for calculating the proportional gain K _SR by the equation 4 (where τ is a target speed response time constant). The speed control device for an elevator according to claim 1, wherein: [Equation 4] [Equation 5]