JPS6025359B2 - Elevator speed control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a speed control device for an elevator, and more particularly to a speed control device that can share a speed command device even if the rated speeds of elevators are different.

Recently, in AC elevators driven by three-phase induction motors, in order to simplify and reduce the cost of the equipment, during deceleration, only the braking force is transferred to the output signal of the AC speed generator (speed feedback signal) and the deceleration position of the elevator. Control is performed according to the deviation from the speed command signal, which decreases accordingly.

In this case, to improve ride comfort and differential floor characteristics,
Generating a speed command signal requires a large number of position signals, but obtaining these by directly detecting the position within the tower would result in an expensive device, so the above motor rotation speed is The traveling position of the elevator is detected by integrating the speed, and the signal obtained thereby is used to generate a speed command signal that decreases in accordance with the deceleration position.

The technique of the sub-chamber will be explained below with reference to FIGS. 1 to 4. Figure 1 is a block diagram of an elevator speed control device.
1 is a reduction gear, 2 is a three-phase induction motor for driving an elevator, 3
1 is a sheep in which a cage 4 and a counterweight 5 are suspended by ropes, and the sheep 3 is driven by an electric motor 2 via a speed reducer 1. 6 is an AC speed generator directly connected to the electric motor 2, 7 is a detector, 8 is a deceleration start position detector,
9 is a deceleration final position detector, and the detectors 8 and 9 generate a position signal when passing the detector 7.

This is a reset signal generation circuit.

The output of the AC speed generator 6 is given to a waveform shaping circuit 11 and a rectifier circuit 17. The waveform shaping circuit 11 shapes the sinusoidal voltage into a square wave voltage and inputs it to the counter circuit 12. . Further, the rectifier circuit 17 converts the signal into direct current, which is then inputted to the comparator circuit 18 as a speed feedback signal. Figure 2 shows the waveform shaping circuit 11 and rectifier circuit 17 in Figure 1.
FIG. 3 is a waveform diagram of each part signal in FIG. 2.

In FIG. 2, the output voltages V, , V of the AC speed generator 6
2, V3 (waveform is shown in Figure 3) with diode 17-1
~17-6 is converted into direct current by a rectifier circuit 17 composed of
This voltage V4, that is, the voltage between terminals 17-7 and 11-7 is defined as a speed feedback voltage.

This speed feedback voltage V4 is the rotational speed N (r.p.
m), and the output voltage of the AC speed generator 6 V,,
Frequency f (HZ) of V2, V3 and rotation speed N (r.p.m
), if the number of poles of the AC speed generator is P, then f
; Since there is a relationship as follows, as the number of poles P increases, the frequency increases and the ripple in the speed feedback voltage V4 becomes extremely small as shown in FIG. 3b.

Next, the traveling position detection pulse is detected between any one AC terminal of the speed feedback voltage detection rectifier circuit 17 and the terminal 11-7.
For example, the voltage across the diode 17-6 between the terminal 17-10 and the terminal 11-7 is taken out and input to the waveform shaping circuit 11.

In other words, this voltage means that the potential of terminal 17-10 is
A positive voltage is output only when the potential is higher than the potential of -8, 17-9, and when it is lower, it becomes a negative voltage of the forward voltage drop of the diode 17-6, and as shown in Figure 3c, a positive voltage is output. rainbow,
This becomes an asymmetric AC voltage on the negative side 1/3T (T is the cycle of V, V2, and V3).

When this voltage is applied to the base of the transistor 11-2 through the resistor 11-1 of the waveform shaping circuit 11, the collector voltage V6 of the transistor 1-2 becomes d in FIG. When the waveform is shaped by the Schmitt inverter 11-2, the output voltage V7 becomes the third
As shown in figure e, a square wave voltage is output during the 2/rainbow period and is not output during the remaining 1/rainbow period. That is, the waveform shaping circuit 11 outputs one pulse during one cycle in synchronization with the output frequency of the AC speed generator 6.

When the elevator travels at the rated deceleration using a power running circuit (not shown) and reaches the deceleration start point, the deceleration start position detector 8 shown in FIG. 1 operates to detect the deceleration start point, and the signal is sent to the reset signal generation circuit. 10 is used as a reset signal, this reset signal releases the reset of the counter circuit 12 and the latch circuit 14, and the counter circuit 12 resets the waveform shaping circuit 11.
The output pulses are divided and input into the decoder circuit 13.

When the number of input pulses of the decoder circuit 13 reaches the set value, the decoder circuit 13 sends out an output, which is transmitted to the latch circuit 14.
, and the traveling position of the electric car is detected.

This position signal is input to the speed command generation circuit 15, and the speed command generation circuit 15 generates a signal that decreases in a stepwise manner as shown in FIG. A speed command signal that smoothly decreases according to the deceleration position shown in is generated and input to the comparison circuit 18. Comparison circuit 18
The speed feedback signal obtained by converting the output of the AC speed generator 6 into DC by the rectifier circuit 17 is compared with the speed command signal described above, and the output of the comparison circuit 18 is inputted to the phase shifter circuit 19. The output of the circuit 19 controls the gate of the thyristor of the mixed bridge circuit 20, which is composed of two thyristors 20--, 20-2 and two rectifiers 20-13, 20-4,
The output of the mixed bridge circuit 20 is supplied to the primary winding of the electric motor 2 to control the dynamic braking force of the electric motor 2 and perform deceleration control of the elevator. When the elevator decelerates and reaches a certain position before the landing point, the final deceleration position of the elevator is detected by the deceleration final position detector 9, and the speed command signal is set to zero based on this signal, and the elevator decelerates and stops. do.

In such an elevator speed command signal generation method, the distance traveled by the elevator corresponding to one output pulse of the waveform shaping circuit 11 (hereinafter referred to as pulse distance).

) P is the diameter of sheave 3, D is the reduction ratio of reducer 1, and i is the diameter of sheave 3.
Then, it is expressed as SoP=23×Mugi ---'1).

Note that D and i are determined by elevator specifications such as the rated speed of the elevator and the power supply frequency. By the way, ``In order to improve the mass production effect, the three-phase induction machine 2 and the AC speed generator 6 are normally of the same specification even if the elevator specifications are different.For this reason, the power supply frequency is the same and the rated speed is the same. If they are different, the rotational speed of the electric motor 2 is the same, so the diameter ○ of the sheave 3 and the reduction ratio j of the reducer 1 are selected for each rated speed. Therefore, if the rated speed of the elevator is different, '1) As can be seen from the formula, if the same speed command device is used when the pulse distance P changes, the elevator traveling distance when the same number of pulses is detected is different, and the rated speed of the elevator is different, the following problems will occur. For example, if the rated speed is 6 h/min and the power frequency is 50 Hz, and the pulse distance is 2.5 h/min, then the average deceleration is 0.5 m, which is considered preferable for ride comfort in this type of elevator. Since the deceleration distance in the case of 5h/mjn is 1, the corresponding number of pulses is 400.
In order to correspond to any position within this deceleration distance of one skin,
If the number of input pulses of the decoder circuit 13 is set to perform multi-stage position detection, the rated speed is 45 m.
/mjn, if used as is in an elevator with a power supply frequency of 50 Hz, the pulse distance SoP in this case would be 1.9 ribs, the traveling distance of the 400th pulse would be 76 ribs, and the average deceleration would be as small as 0.37 m/min. This increases driving time. Also, since only the braking force is controlled during deceleration, a certain amount of inertia is required in the mechanical system, but in the case of a long deceleration distance as mentioned above, the inertia must be increased, which reduces power consumption. As the amount increases, the motor capacity and power supply equipment capacity must be increased.

If the same speed command device is used when the rated speeds are different, the above-mentioned problem will occur, so conventionally, a speed command device designed to suit each rated speed of the elevator has been used.

As a result, the number of types of circuits increases, causing an increase in costs. The present invention has been made in view of the above, and an object of the present invention is to provide a speed control device for an elevator in which the same speed command device can be used even if the rated speeds are different.

The feature of the present invention is that when the rated speed of the elevator is low,
Among the traveling positions detected by the traveling position detection device, which detects the traveling position of the elevator by integrating the number of pulses of the pulse signal output by the pulse signal generator, which generates a pulse signal proportional to the rotation speed of the elevator driving electric motor. The above object can be achieved by simply changing the speed command circuit section corresponding to a travel position that is equal to or greater than a predetermined pulse integrated value. The present invention will be explained in detail below with reference to the embodiments shown in FIGS. 5 and 9 and FIGS. 6 to 8.

FIG. 5 is a circuit diagram showing an embodiment of the speed command device of the speed control device of the present invention.
0, parts corresponding to the counter circuit 12, decoder circuit 13, latch circuit 14, and speed command circuit 15 are shown,
The overall configuration of the speed control device is the same as that shown in FIG.

In FIG. 5, the contact 9a of the deceleration final position detector 9 shown in FIG. 1 is configured to be closed from the time the elevator is started until the time when the deceleration final position is detected.

Also, until the elevator reaches the deceleration starting point,
Since the deceleration start position detector 8 in FIG. 1 does not operate, its contact 8a is open, and the transistor 10-4 is non-conducting, so the output of the Schmitt inverter 10-6, which is made up of an integrated circuit, is " 0”, output of 10-7 is “1”
It is in a state of On the other hand, the output of the AC speed generator 6 is input into the counter 12, and the pulse is waveform-shaped by the waveform shaping circuit 11, but the output of the inverter 10-7, which is the reset signal for the counter 12, is "1". Therefore, the counter 12 is in a state where counting is prohibited (assuming that the counter 12 used in the embodiment of the present invention starts counting when the reset signal is "0").

Therefore, since the outputs of the counter 12 are all "0", when this is inputted to decoders 13-1 to 13-5 consisting of 3-input NAND elements, the outputs are all "1", while 2 Since the output of the inverter 10-6, which is the reset signal for the latches 14-1 to 14-5 composed of the input NAND elements, is "0", the latch 1
The outputs of 4-1 to 14-5 are all "0", and therefore, the outputs of the open collector inverters 15-1 to 15-6, which are configured by integrated circuits, are also all "1" and maintain a high impedance state. There is.

15-16 are contacts, and the contacts 15-16 are opened in the case of an elevator with a high rated speed.

Therefore, in this case, decoder days 3-1 to 13-5
All position signals detected by will be used. In addition, depending on the rated speed of the elevator, there are restrictions on the amount of deceleration from the viewpoint of riding comfort, but the deceleration distance given by this is, for example, when the rated speed is 6 h/m.
In the case of an in-class elevator, the average deceleration is 0.5 h.
At s2, the deceleration distance is about lm. Then, an appropriate position within this deceleration distance is detected and a speed command that decreases depending on the position is created, but the number of detected positions is determined from both elevator performance and cost. In the embodiment of the present invention, the number of position detection points is seven including detection of the deceleration start position and deceleration final position by the position detectors 8 and 9 (see Figure 1), and the deceleration is constant and between each detection position. The positions are detected so that the speed differences between the two are equal, and the relationship between distance and speed is as shown in FIG. 8A, which will be described later. In addition, since the position to be detected (distance from the landing point of the elevator) SH, ~SH5 can be found from Fig. 8A,
The number of pulses P, -P5 corresponding to these positions can be calculated from the pulse distance (traveling distance per pulse). Then, the number of pulses P, ~P5 is sent to the decoder 13.
-1 to 13-5, and the next latch 14-1 to 14-
5 and the elevator running position SH, to SH5 is detected. Note that the deceleration start position SHo and the deceleration final position SH6 are detected by position detectors 8 and 9. Figure 6,
The diagram in FIG. 5 is a time chart for explaining the operation in FIG. 5, and the operation in FIG. 5 will be explained below with reference to FIGS. 6 and 7.

When the elevator reaches the deceleration start point (time t,), the deceleration start position detector 8 is activated, its contact 8a is closed (FIG. 6b), and the output of the inverter 10-6 becomes "0" → “
1” [Figure 6c], the output of inverter 10-7 is “1”
→ changes to "0" (Fig. 6 d), the counter 2 starts counting (Fig. 6 e), the latches 14-1 to 14-5 are released from reset, and the decoders 3-1 to 13-1 are released. Provision is made for storing the outputs of 5.

At this time, the output of the open collector inverter 5-1 changes from "1" to "0" [Fig.
7 is grounded and the speed command is lowered as shown in Figure 6 w.

Then, the counter 12 is 1, 2, 4, 8, ..., 2n
-2,2n-1 When counting the number of pulses expressed in decimal notation, the output terminals 1,2,3,...n
12, n-1, and n sequentially, and these outputs are combined and input to decoders 13-1 to 13-5.

For example, when output terminals 2, 3, and 5 are input, decoders 3-1 to 13-5 output counter outputs 2, 3, and 5.
4 and 16 are combined and output at the 22nd pulse (21416=22). However, in this case, the decoder 13-1-1
Since 3-5 are NAND elements, "1''→''
0'' [Fig. 6 f to j].

By such a method, the number of pulses P, ~P5 obtained in A of Fig. 8, which is a relationship diagram between distance and speed when decelerating at a constant deceleration, is detected by the decoders 13-1 to 13-5. and inputs this to latches 14-1 to 14-5.

As a result, the outputs of the latches 14-1 to 14-5 change from "0" to "1" as shown in FIG. 6, k to o, and are stored and position detected. Then, when this output is input to inverters 15-2 to 15-6 with open collectors,
The outputs of the inverters 15-2 to 15-6 are shown in Fig. 6 g to v.
As shown in the figure, the resistors 15-8 and 15-9, 15-9 and 15-10, 15-10 and 1 change from "1" to "0".
5-11, 15-11 and 15-12, 15-12 and 15
-13 are grounded in sequence to create a reference speed command that descends stepwise in accordance with the deceleration position of the elevator, as shown in FIG. 6w. This step-like voltage drop is smoothed by the next deceleration command smoothing circuit 16 (see FIG. 1), resulting in a speed command that smoothly decreases as shown by the dotted line in FIG. 6 w.

Note that the voltage that drops stepwise in FIG. 6 w is applied to the resistors 15-7 to 16- in FIG. Set the resistance value of 14.

When the elevator decelerates and the deceleration final position detector 9 detects the final position, its contact 9a closes and resistor 15-
The series circuits 7 to 15-14 are disconnected from the power supply 21, and the speed reference command is set to zero.

When the elevator stops and a stop signal is generated, the deceleration start position detector 8 is configured to be deactivated, so its contact 8a opens and the inverter 10-6 The output of is “0”, the output of 10-7 is “1”
As a result, the latches 14-1 to 14-5 are reset, the force counter 12 is prohibited from counting, and the counter 12 and latches 14-1 to 14-5 are reset to the deceleration start point of the next operation. Next, the operation of elevators with the same power supply frequency and lower rated speed will be described.

When lowering the rated speed, use the elevator drive motor 2.
The specifications of the AC speed generator 6 and the AC speed generator 6 are the same as when the rated speed is high, and the reduction ratio of the reducer 1 and the sheave 3 shown in FIG.
Lower the rated speed by changing the diameter of the Therefore, in this case, the pulse distance becomes smaller corresponding to the rated speed. Therefore, if the same number of pulses are counted when the rated speed is low as when the rated speed is high, the corresponding distance traveled by the elevator will be shorter. Therefore, when the rated speed is low, in order to match the landing points, the detection position by the deceleration final position detector 9 shown in Fig. 1 is left as is, and the detection position by the deceleration start position detector 8 is also changed, which may cause problems in riding comfort. No deceleration is obtained to shorten the distance.

That is, the detection position by the deceleration start position detector 8 is
It is installed at the SL point in the figure, and from the viewpoint of riding comfort, the deceleration is set to be smaller and constant than when the rated speed is high, and
The position corresponding to the same number of pulses as when the rated speed is high is detected. In other words, the relationship between distance and speed is
Do as shown in Figure 8.

In this case, the position corresponding to the number of pulses P4 at the entrance in FIG.
, P5 can be removed.

Therefore, in the present invention, the resistors 15-11, 15-1 create a descending command corresponding to the pulse numbers P4 and P5.
2 are short-circuited using pocket points 15 and 16 to reduce the number of steps the reference speed command descends.

In this case, when the elevator reaches the deceleration start point (position SL in Figure 8) and the deceleration start position detector 8 is activated, the pulse numbers P, , P2, and P3 are Decoders 3-1 to 13-3, latches 14-1 to
The outputs of 14-3 and inverters 15-1 to 15-4 are as shown in f to h, k to m, and p to s in FIG. descend in a shape.

Also, when the elevator decelerates and reaches the final deceleration position,
Since the deceleration final position detector 9 is activated and its contact 9a is closed, the reference speed command becomes zero. At this time, the resistance values of resistors 15-7 to 15-13 are the same as when the rated speed is high, and the maximum value of the reference speed command voltage obtained from output terminals 15-15 is adjusted with resistors 15-13. Even if the speed command value corresponding to the layer does not become a set value as shown by the dotted line in FIG. 8, it is possible to obtain performance with no problems in practice.

Note that even better performance can be obtained by adjusting the resistance values of all the resistors 15-7 to 15-13. Fifth
According to the embodiment shown in the figure, when the rated speed of the elevator is high, the contacts 15 and 16 are connected to the decoder 3-1.
decoder 13-4, which creates a speed command using the position signal detected by ~13-5, and closes contacts 15-16 to detect a large number of pulses when the rated speed of the elevator is low; The position signal detected by contacts 13-15 can be disabled, and the speed command can be created by detecting the same number of pulses as when the rated speed is high. The speed command device can be shared by simply selecting whether to open or close.

Therefore, it is possible to reduce the number of circuit types, and an economical speed control device can be achieved. FIG. 9 is a circuit diagram corresponding to FIG. 5 showing another embodiment of the present invention.

In FIG. 9, when the rated speed of the elevator is high, the reference speed command voltage is taken out from the output terminal 15-15 as in FIG. It is taken out from the output terminal 15-17 connected to the connection point with. Note that the contacts 15 and 16 shown in FIG. 5 are not provided, and the other parts of the circuit are the same as those shown in FIG. In this case, the position detected by the decoders 13-4 is set to be equal to or behind the position detected by the deceleration final position detector 9, and the rated speed of the elevator is low. In this case, the reference speed command voltage is taken out from the output terminals 15-17, and the position signals detected by the decoders 13-4 and 13-5 in the same machine as in FIG. 5 are made invalid.

However, if the resistance values of resistors 15-7 to 15-14 are set to the same value as when the rated speed is high, the maximum value of the reference speed command voltage obtained from the output terminals 15-17 will be lower than in the case of Fig. 5. Therefore, set the maximum value of the speed feedback signal to a value close to this value, or adjust the resistance value of resistors 15-14 so that the same maximum value of the reference speed command voltage as in the case of Fig. 5 is obtained. Make it.

Furthermore, if the resistance values of the resistors 15-7 to 15-13 are also adjusted, even better performance can be obtained.
Same as the figure. As explained above, according to the present invention, when the traveling position of the elevator is detected by integrating the rotational speed of the elevator driving electric motor, and when creating a speed command that decreases in accordance with this position signal, the rated speed of the elevator is Even if the speeds are different, even if the pulse distance is proportional to the rated speed, the speed command circuit can be shared, which has the remarkable effect of reducing the number of circuit types and improving economic efficiency. .

[Brief explanation of the drawing]

Figure 1 is a block diagram of the speed control device for an AC elevator.
Figure 2 is a circuit diagram of the waveform shaping circuit and rectifier circuit in Figure 1, Figure 3 is an explanatory diagram of the operation of Figure 2, Figure 4 is a speed command characteristic diagram of Figure 2, and Figure 5 is a diagram of the present invention. A circuit diagram showing an embodiment of the speed command device of the speed control device, FIGS. 6 and 7 are time charts for explaining the operation of FIG. 5, and FIG. The relationship diagram between distance and speed, FIG. 9 is a rotation diagram corresponding to FIG. 5 showing another embodiment of the present invention. 1... Reduction gear, 2... Three-phase elevator drive Induction motor, 3...Sheave, 4...Elevator car
6...AC speed generator 8...Deceleration start position detector, 8a...8 contact, 9...Deceleration final position detector, 9a...9 contact, 10...Reset Signal generation circuit, 10-4...transistor, 10-6, 10
17... Inverter with Schmitt, 11... Waveform shaping circuit, 12... Counter circuit, 13...
...Decoder circuit, 13-1 to 13-5... Nacoder, 14...〇Latch circuit, 14-1 to 14-5...
... Latch, 15 ... Speed command generation circuit,
15-1~15-6...Open collection inverter, 15~? ~15-14...Resistance, 1
5-15, i5-17...Output terminal, 15-Kado6.
·…·contact. Figure 2, Figure 3, Figure 4, Figure 5, Figure 5, Figure 7, Figure 7. figure

Claims (1)

[Scope of Claims] 1. An elevator car whose rated speed is determined by adjusting the reduction ratio or sheave diameter of a reduction gear or sheave connected to an elevator driving electric motor, and the elevator driving electric motor. a pulse signal generator that generates a pulse signal proportional to the rotation speed; a means for integrating the number of pulses of the pulse signal after the deceleration start point of the elevator; A traveling position detection device that sequentially generates a position signal each time the integrated value reaches the set value, and a plurality of resistors connected in series are sequentially short-circuited according to the position signal, and a staircase is connected from the series connection end. The elevator is equipped with a device that generates a speed command signal that gradually decreases, and controls the speed of the electric motor according to a deviation between the speed command signal and the speed feedback signal. When the rated speed of the car is set low, the deceleration start point is set as the deceleration start point from the low rated speed, and the speed command signal generator is short-circuited by a position signal in which the integrated value is equal to or higher than a predetermined value. A speed control device for an elevator, characterized in that the resistor is short-circuited in advance or a speed command signal is output from the low voltage side of the resistor. 2. The elevator speed control device according to claim 1, wherein the pulse signal generator comprises means for waveform shaping the output of an AC speed generator for detecting a speed feedback signal, which is directly connected to the elevator drive motor. 3. The elevator speed control device according to claim 1, wherein the voltage of the speed feedback signal at the rated speed is set to match the voltage of the rated speed command signal.