JPS6127882A - Controller for speed of elevator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] This invention relates to an improvement in a device for controlling the speed of an elevator.

[Prior art]

In a rope elevator, the elevator car, counterweight, and other mechanical elements, as well as the main rope that suspends them from the hoist, constitute a so-called spring-mass system. In this spring/mass system, the transfer function from the torque generated by the motor to the rotational speed of the motor is generally expressed by the following equation.

Here, T: Electric motor generated torque 艷: Motor rotation speed J: Equivalent moment of inertia of the elevator mechanical system converted to the motor rotor axis A1 to Fi: Car position, car load, and other mechanical elements in the hoistway, respectively. As is clear from the equation, the spring-mass system in an elevator generally has multiple resonance points and anti-resonance points, and at each resonance point there is a second-order lag system with a small damping constant. In particular, in elevators with high tjNl, the frequency of the resonance point is low, and as shown in Fig. In many cases, the value is close to the crossover frequency when the function is plotted on a Bode diagram. As a result, the gain at the resonance point of the elevator speed control system including the above-mentioned spring/mass system cannot be of sufficient quality on the Bode diagram. This is because the crossover frequency of the speed control system cannot be set below a predetermined value in terms of the responsiveness of the system and the landing performance of the elevator. Therefore, a torque disturbance generated by some kind of electrical or mechanical excitation force induces vibration within the car without being attenuated. In order to suppress such squirrel cage vibration, for example, as shown in Japanese Patent Publication No. 5B-208'22, constant gain and phase compensation is applied to the speed feedback signal obtained by the speed detector coupled to the motor. It has been proposed that the output signal is used as a squirrel cage vibration suppression signal and is superimposed on the torque command signal of the electric motor to control the electric motor. The main points are shown in Figs. 2 and 3.

In the figure, R, S, and T are three-phase AC power supplies, and (1) is AC power supply R.
. (2) is the armature of the DC motor connected to the power converter (1) (field is omitted), (3) is the armature (
2) is a drive sheave for the hoist, and (4) is a speedometer generator that is directly connected to the armature (2) and detects the rotational speed of the armature (2) and generates a speed signal (4a). (5) is a sheave, (3) K is wrapped around the main rope, (
6) and (7) are the heel and counterweight of the elevator connected to both ends of the main rope (5), respectively, and (8) is the current signal (8a) that detects the current flowing through the armature (2). )
(9) is a speed command signal, (10
a is a torque command generation circuit that generates a torque command signal (1Oa) from a speed command signal (9) and a speed signal (4a);
υ is a vibration suppression circuit consisting of a bandpass filter, and its transfer function is expressed by the following equation (■).

Here, K: filter gain T, T2: filter time constant S: Laplace operator (lla) is the vibration suppression signal output from the vibration suppression circuit αυ,
(6) is the torque command signal (1Oa) and the current signal (8a)
(13 is a converter control circuit that supplies the output corresponding to the output of the adder (6) to the power converter (1) K; 0, that is, the power converter; The armature (2) is rotated by the direct current converted by the device (1), and the heel (6) runs via the sheave (3).The rotation speed of the armature (2) is detected by the speed detector (4). The speed signal (4a) is detected by the torque command generation circuit (1
given to 0. The torque command signal (40a) generated from the torque command generation circuit (10) is input to the adder (2), and a deviation signal from the current signal (jJa) is calculated.
The output of the adder @, on which the vibration suppression signal (lla) to be described later is superimposed, is input to the converter control port FjIrQl. The converter control circuit Q3 controls the power converter (1) according to the input.
) to control the firing angle of the thyristor, armature (2)
The applied voltage changes, and the rotational speed of the armature (2), that is, the running speed of the car (6), is automatically controlled with high precision.

Now, when vibration occurs in the spring/mass system, the vibration distribution is detected by the speed detector (4) and input to the vibration suppression circuit θυ. The vibration suppression circuit 0υ is composed of a bandpass filter as described above, and low frequency components and high frequency components are removed and vibration suppression is extracted to produce a vibration suppression signal (11a). Then, this vibration suppression signal (11a
) is inputted to the adder (6) K with the opposite polarity so as to induce a vibration having an opposite phase to the vibration occurring in the heel (6), and is superimposed on the torque command signal (10a). As a result, the power converter (1) is controlled by the control signal on which this vibration suppression signal (114) is superimposed, and the armature (2)
The generated torque also changes accordingly, and the vibration inside the car (6) is suppressed.

However, especially when the shaft deflection of the armature (2) is the cause of the above-mentioned excitation force, the vibration included in the rotation of the armature (2) shaft is larger than the amplitude of the circular vibration of the car (6). Since the magnitude of the component is small, the speed detector (4) that detects the rotation of the shaft of the armature (2) cannot detect a sufficiently large vibration component. Also, increase the gain of the vibration suppression circuit 01), which includes differential operation to shift the phase, to extract vibration components of sufficient size! Even if you try, it will only unnecessarily amplify other noise components and will not be effective vibration suppression signal (lla
) cannot be obtained. In addition, when the car (6) goes up and down, the transfer function of the mechanical system changes due to changes in the length of the main rope (5) from the car (6) to the sheave (3) and changes in the mass position. ) The vibration may be amplified depending on the position of the car.
By using the i suppression signal and controlling the above gain or phase compensation amount according to the car position, even if the cause of car circular vibration is due to deflection of the motor shaft, etc., it can be uniformly suppressed regardless of the car position. An object of the present invention is to provide an elevator speed control device that can suppress car circular vibration.

[Embodiments of the invention]

First, the principle of this invention will be described.

FIG. 4 shows a change in the phase difference between the torque command signal and the car circular vibration waveform depending on the car position in the hoistway, with reference to the phase of the torque command signal.

As shown in the figure, the phase difference between the two signals is rotated by about 180 degrees at the top and bottom of the hoistway, and the change roughly follows a sine function. Therefore, conversely, from the relationship in this diagram,
If a signal having a predetermined phase difference with respect to the car circular vibration waveform is superimposed on the torque command signal (LOA) as a vibration suppression signal depending on the car position in the hoistway, ultimately
) It should be possible to suppress the vibrations in the cage (6) by inducing vibrations that are in the opposite phase to the vibrations occurring in the cage (6).

Figure 5 shows the above in a vector diagram, where 'ofr is the vector of the vibration waveform generated within the heel (6), ■2
,. . is vector F. 8r, the phase difference α between them changes according to the relationship shown in FIG. 4. 〒. . , Fi is the vector of the vibration suppression signal superimposed on the torque command signal according to the present invention, and has a phase difference θ (180°-α) from the vibration waveform vector Fear, and the vibration waveform vector is within the angle (6) according to the relationship shown in FIG. F
6. ．． A vector F0゜□ of vibration components having an opposite phase is generated.

That is, based on the vibration waveform vectors F, ..., r occurring in the car (6) according to the car position, vibrations having a predetermined phase difference of 0 as shown in Figs. 5 and 6 are generated. Suppression signal vector〒. . , and superimposes it on the torque command signal (LOA) to effectively suppress vibrations within the car (6).

7 to 12 show an embodiment of the present invention.

In Figures 1 and 8, the load signal (14a) corresponding to the passenger load amount of the car (6) is installed under the floor of the car (6).
), the load force is generated by pulleys installed at the top and bottom of the hoistway; Tape with symbols such as signs, A frame is installed in the hoistway, and by reading the symbol on the tape (L7)
), Ql is a vibration suppression circuit that generates a vibration suppression signal (19a) according to the car position signal (18a) from the load signal (14a); is a bandpass filter consisting of an operational amplifier, a resistor, and a capacitor and extracts the vibration component from the load amount sp, (laa), and (20a) is the gain G corresponding to the vibration component signal and the heel position signal (XSa).
11. G2i and time constant T, and a gain/phase compensation element having a transfer function expressed as a film shape, which compensates for a predetermined lead or lag in the gain and phase of the input according to the car position signal (18a)'. Add. (21a) is the compensation signal outputted from the compensation element (21a), and (a) is a sign inverting circuit with a gain of -1 composed of an operational amplifier and a resistor, the output of which is the vibration suppression signal (19a).

FIG. 9 shows the overall configuration of the compensation element QD. In this embodiment, the vibration component signal (20a
) and the car position signal from the car position detection device 0 (18
The car position determining means e13, which receives a) as an input, determines whether the car (6) is above or below the center of the hoistway, and based on its output, the gain/phase compensation calculation means (
c), it is configured to add a predetermined lead or lag compensation to the gain and phase of the vibration component signal (20a) and output a compensation signal (21a). 〇Figures 10 and 11 show the compensation element e1 ．． ]) is configured by a microcomputer.

In the figure, (21A) is the central processing bag fff (cPU), (
21B) is a program and a time constant T set corresponding to the car position signal N, (i=1.z, . . . m) as shown in FIG. 11, and a gain G, , G2. A read-only memory (ROM) stores the values of , and the time constant T1 is T, . . . corresponding to the car position signal N .
・T, ...T, is set, and the gain G1i is (6)
If it is below the center, it is set to 0, and if it is at or above the center, it is set to G11...G1ff1,
Gain G2. If the heel (6) is at or above the center, set it to 0; if it is below the center, set it to G...G
It is set to 2/-1. (21C) is a read/write memo I) (RAM), (2
1D) outputs the bandpass filter output (20a) to the CPU
(21A), the input port @ (F/F), which constitutes the converter for inputting the car position signal (18
a) Input circuit for importing, (21F) is CPU
This is an output circuit constituting a converter for emitting the output signal from (21A) as a compensation signal (21a).

Next, the operation of this embodiment will be explained.

When vibration occurs in the car (6) due to deflection of the shaft of the armature (2), etc., the vibration component is detected by the load detector aΦ as vibration of the heel and floor, and a load signal containing the vibration component is detected. (14a) is input to the vibration suppression circuit Q. The load signal (14a) is passed through a band pass filter 4, where low frequency components and high frequency components are removed, and only the vibration components necessary for the vibration suppression circuit are extracted. This vibration component signal 8 (20a)
It is converted into a digital signal via the FiI/F (21D) and taken into the CPU (21A).

On the other hand, the position of the car (6) is constantly detected by the car position detection device (to), and the car position signal (18a) is input to the vibration suppression circuit US and sent to c via I/Ii' (21E).
It is taken into P U ('z1A).

Next, the operation of 1 compensation element Elo is performed in ROM (21B) K
The operation of the stored program will be explained using a flowchart (FIG. 12). It is assumed that this program is repeatedly executed at a period of ΔT.1. First, it is determined by step CL whether the number k indicating the operation ordinal number is 1, that is, whether this is the first operation. , if it is the first time, the state variable x (k) is set to 0 in step 0. Vibration component output (2oa) u (k) and car position g1M (18a) in procedure -
Enter. Next, a car position determination operation is performed in one move i to p. This operation is based on the input car position signal (lea
), it is determined whether the car position is at or above the center N of the hoistway, or below the center N, and as a result, the gain/phase compensation calculation consisting of the following procedure is performed. It will be done. This operation is performed using the Laplace operator s′! The calculation is performed using an arithmetic expression obtained by converting the first-order lag element of the above 0 expression using &: into two. For example, the above equation 0 is expressed as a first-order slow representation.

y (k) = G,, x (ic)
...°■Here, x(k+1):(k+yu)
Compensation signal e in the th calculation to the value y(k) of the state variable in the th calculation: When it is determined that the car position is at or above the center N in the bottom of natural finance procedure ■, the step) Based on formula 0, ROM (21B
), read the value stored in y (k) = G11
When x (k) is calculated and it is determined that the car position is below the center part N7, in step -, based on the same formula 0,
The value x(k+1) of the (k+1)th (second in this case) state variable is calculated by y(k)=. In step (to), the ordinal number k is set to +l (2 in this case). Compensation signal y (k) in procedure (to)? : Output 0 In the next calculation cycle, since the ordinal number is 2, the process proceeds from step G1) to move JItM, and moves 1-(to) to (to) are executed in the same manner as described above. That is, the value x(k+1) of the state variable calculated in step (b) is x(k+1) of step -1
k) and the compensation signal y (k) is calculated.

That is, when the car position is below the center part N, the gain G2, 75E shown in FIG. 11 is read (G
, ,=O), the compensation signal (21a) is expressed in -film form as GS
The phase of the input vibration component value '1+(20a), which forms a phase lead compensation signal i/(l+Ti5), is advanced by a phase difference θ as shown by the dashed line in FIG.

Also, when the car position is at the center N or above it, the gain G1i is read (G2.=O) and the compensation a
Ji+(21a) tj: G1i/(1+T1.
), which delays the phase of the input vibration component signal (201L) by the phase difference θ as shown by the dashed line in FIG.

In this way, the compensation signal 1xa) to which gain and phase compensation has been added is further shifted in phase by 180° by inverting its sign in the sign inversion circuit (2), and the compensation signal (21
a) is converted into a vibration suppression signal (19a) having a phase difference shown by the solid line in FIG. The vibration suppression signal (19a) obtained as described above is an isometric torque command signal vector E1, which generates vibrations within the heel (6) as shown in FIG. . and the vibration suppression signal i with the opposite phase. . , becomes. This vibration suppression signal i. . .

is superimposed on the torque command signal (loa), and vibrations within the heel (6) are ultimately suppressed.

In addition, although the speed control of a DC motor is shown in the embodiment, it is also applicable to a method in which an induction motor is used and a so-called vector control is applied to this to control the torque command component of the induction motor. .

Furthermore, although the load detector a4 is used to obtain an acceleration signal within the car (6), the present invention is not limited to this, and an accelerometer may be installed in the car (6) and its output may be used. The displacement of other equipment in the hoistway or machine room that vibrates in a predetermined phase relationship with the heel (6) may also be used.

〔Effect of the invention〕

As described above, in this invention, the vibration of an elevator car is detected, the gain and phase of this vibration component signal are compensated to generate a vibration suppression signal, and the compensation amount of the gain or phase is controlled according to the car position. Even if the cause of vibration inside the car is due to deflection of the motor shaft, etc., the vibration inside the car can be uniformly suppressed regardless of the position of the car.

[Brief explanation of the drawing]

Fig. 1 is a Bode diagram showing the transfer characteristics of an elevator speed control system, Fig. 2 is a configuration diagram showing a conventional elevator speed control device, and Fig. 3 is a transfer characteristic of the vibration suppression circuit shown in Fig. 2. The block diagram and FIGS. 4 to 12 are diagrams showing an embodiment of the elevator speed control device according to the present invention, and FIG. 4 shows the change in the phase difference between the torque command signal and the vibration in the car depending on the car position 'fI: The characteristic diagram shown, JX5 diagram, is a Peltle diagram showing the principle of this invention. Figure 6 is a characteristic diagram showing the change in the phase difference of the vibration suppression signal depending on the car position. The seventh factor is a configuration diagram of the speed control device. Figure 8 is a block circuit diagram of the vibration suppression circuit in FIG. 7, FIG. 9 is an overall configuration diagram of the compensation element in FIG.
The figure shows a specific configuration diagram of the compensation element in Figure 8, and Figure 11 shows the compensation element in Figure 1.
FIG. 0 is an explanatory diagram of the contents of the ROM, and FIG. 12 is a flowchart of the operation of the compensation element in FIG. In the figure, (1) is the power converter, (2) is the armature of the DC motor, (6) is the elevator car, (10 is the torque command generation circuit, Q'4 is the adder, and α is the load detector. (vibration detection device), (to) heel position detection device, α is a vibration suppression circuit, kiln is a band pass filter, c2υ is a compensation element, (a) is a sign inversion circuit, kiln heel position determination means, (h) ) is the gain/phase compensation calculation means 0. Note that the same reference numerals in the figures indicate the same parts.

Claims (3)

[Claims] (1) A vibration detection device for detecting vibrations of the car, in which the speed of the car is controlled by controlling the torque of the hoisting motor using a control signal obtained by superimposing a vibration suppression signal on a torque command signal; A car position detection device that detects the position of the car, and a gain and phase of the output signal of the vibration detection device are compensated and emitted as the vibration suppression signal, and the compensation amount of the gain or phase is outputted from the car position detection device. An elevator speed control device characterized by comprising a vibration suppression circuit that controls according to a signal. (2) An elevator speed control device according to claim 1, wherein the hoisting motor is a DC motor. (3) An elevator speed control device according to claim 1, wherein the hoisting motor is an induction motor.