WO2013094255A1

WO2013094255A1 - Elevator control device and control method therefor

Info

Publication number: WO2013094255A1
Application number: PCT/JP2012/073073
Authority: WO
Inventors: 酒井　雅也
Original assignee: 三菱電機株式会社
Priority date: 2011-12-23
Filing date: 2012-09-10
Publication date: 2013-06-27
Also published as: JPWO2013094255A1; JP5746373B2

Abstract

A control device for a traction-type elevator provided with a control status determination part (17, 317, 517, 717) which determines, in accordance with the control status and the control conclusion status of a control system of an electric motor on start-up of an elevator, whether to alter the response speed of the speed control of the electric motor or to switch over from position control of the electric motor to speed control, and which performs switchover from position control to speed control and alters the speed control response speed, in order to stably mitigate start-up shock and rolling back of the cage etc., regardless of the magnitude of unbalanced torque.

Description

Elevator control device and control method thereof

This invention relates to an elevator control device or the like that reduces the start shock at the start of elevator travel.

Generally, in a rope-type elevator, a car and a counterweight are suspended in a tang shape via a drive sheave (traction type). When the car is stationary, the car is held stationary by the brake, but at the start of traveling, the brake is released and the drive sheave is rotated by the electric motor to move up and down. At this time, as the brake is released, the unbalance torque of the weight difference between the car and the counterweight is transmitted to the motor. However, if the brake is released with the motor torque being zero, the start shock and the car roll back due to a delay in the control response. Etc. occur. For this reason, in order to reduce the start shock, the rollback of the car, etc., a start control method that detects the load weight of the car and generates a torque that cancels the unbalance torque by the electric motor and then releases the brake is generally used. Has been done.
However, this method requires a load detection device for detecting the load weight of the car and increases the cost. Furthermore, it is necessary to install and adjust the load detection device at the time of installation. In view of the above, a control method has been proposed that reduces the start-up shock, rollback, and the like without using a load detection device.

For example, Patent Document 1 below proposes a control method that reduces the start-up shock by temporarily increasing the response of the speed control amplifier during start-up.
Further, in Patent Document 2 below, the torque response speed of the inverter control device is set higher than the braking torque change speed when the brake is released at the start, and the moving direction and the moving amount of the car at the start are detected, The inverter control device is fed back in a direction to cancel the movement amount.

Generally, if the response of the speed control system and torque control system (current control system) is increased, it will become unstable. This is particularly noticeable in the slow region at startup. As a speed detector, it is common to detect speed by measuring pulses with an encoder or the like. However, since the pulse change is small at a very low speed, digital control using a microcomputer or the like is relatively less than at high speed. In addition, the speed detection error and the speed detection time delay become large. This is the reason why the control becomes unstable. For this reason, even if the control response is sufficiently large so that the starting shock can be reduced when the unbalance torque is large, such as when the car is almost empty or when the car is almost full, the load state of the car is not changed. When the unbalance torque, which is close to the weight of the weight, is small, there is a problem in that it is easily destabilized because the pulse change is small. From the above, there is a problem that the control response cannot be sufficiently increased, and the start shock and the rollback of the car cannot be sufficiently reduced when the unbalance torque is large.

Japanese Patent Laid-Open No. 60-040386 JP 62-004180 A

This invention is for solving the above-described problems, and provides an elevator control device and the like that stably reduce the start shock and the rollback of the car regardless of the magnitude of the unbalance torque.

A control state determination unit that determines the control state of the control system based on a control signal in the control device is provided, and the control device is switched based on the determined control state.

The elevator control device or the like according to the present invention includes a control state determination unit that determines a control state of the control system based on a control signal in the control device, and switches the control unit based on the determined control state. Thus, it is possible to stably reduce the start shock, the rollback of the car and the like regardless of the magnitude of the unbalance torque.

It is a block diagram which shows the control apparatus of the elevator by Embodiment 1 of this invention. It is a figure explaining the determination method of the control state in Embodiment 1 of this invention. It is a block diagram which shows the control apparatus of the elevator by Embodiment 2 of this invention. It is a block diagram which shows the control apparatus of the elevator by Embodiment 3 of this invention. It is a block diagram which shows the control apparatus of the elevator by another example of Embodiment 3 of this invention. It is a block diagram which shows the control apparatus of the elevator by Embodiment 4 of this invention. It is a figure which shows the operation | movement flowchart of the control apparatus of the elevator in Embodiment 4 of this invention. It is a block diagram which shows the control apparatus of the elevator by Embodiment 5 of this invention. It is a figure which shows the operation | movement flowchart of the control apparatus of the elevator in Embodiment 5 of this invention.

Hereinafter, an elevator control device according to the present invention will be described with reference to the drawings according to each embodiment. In each embodiment, the same or corresponding parts are denoted by the same or corresponding reference numerals, and redundant description is omitted.
Embodiment 1 FIG.
1 is a block diagram showing an elevator control apparatus according to Embodiment 1 of the present invention. In the figure, a car 11 and a counterweight 12 are suspended from both ends of a suspension means 10 hung on a drive sheave 6. The suspension means 10 is configured by, for example, a plurality of ropes or a plurality of belts. The drive sheave 6 is driven by the electric motor 5, and the car 11 and the counterweight 12 are raised and lowered in opposite directions (traction type). The electric motor 5 has a brake 9 for braking the rotation. The brake 9 is braked and released by the brake control unit 20. The brake 9 is constituted by a disc brake or a drum brake, and the brake 9 is in a braking state while the car 11 is stopped.
A speed / position detector 8 is connected to the electric motor 5, and a signal corresponding to the amount of rotation of the electric motor 5 is output. As the speed / position detector 8, an encoder or a resolver is generally used, and a pulse or voltage corresponding to the rotation amount is output. The speed calculation unit 21 calculates the rotational speed (calculated value) ω of the electric motor using the signal output from the speed / position detector 8. The speed / position detector 8 and the speed calculator 21 constitute a speed detection calculator.

In the low speed state including when the car 11 is stationary immediately after the elevator is started, the output change of the speed / position detector 8 is relatively small. For this reason, the signal change during the calculation cycle in which the speed calculation unit 21 calculates the rotational speed ω is also relatively small, and the error in the calculation speed and the calculation time delay with respect to the actual speed are relatively large compared to when driving at high speed. Become. For this reason, if the control gain is increased in order to increase the response speed of a control system such as speed control, it is likely to become unstable during low-speed traveling.

The electric motor 5 is driven by the inverter 4. The inverter 4 is generally a PWM (pulse width modulation) inverter, and outputs a drive voltage for driving the motor 5 to the motor 5. The drive voltage command value is generated by the drive signal generator 13. The AC voltage of the power source 1 is converted to DC by the converter 2, the DC voltage is smoothed by the smoothing capacitor 3, and the smoothed DC voltage is input to the inverter 4. The current of the electric motor 5 is detected by a current detector 7.

The electric motor 5 is generally driven and controlled by speed control. In the present invention, a plurality of speed control units are provided, and when the elevator starts, the control state determination unit 17 operates the switching unit 18 according to the control state to switch the plurality of speed control units (15, 16). It is characterized by controlling. In FIG. 1, there are two speed controllers A15 and a speed controller B16 that is more responsive than the speed controller A15. The switching unit 18 is a control device that switches between two speed control units A15 and B16. The elevator control apparatus in the present embodiment is indicated by reference numeral 22 in FIG. Hereinafter, these operations will be described.

The speed command generator 14 outputs a speed command value ω ^* obtained by converting the traveling speed pattern of the elevator car 11 into the rotational speed of the electric motor 5. When the elevator is started, a speed command value for holding the car stationary is output from the speed command generator 14 before the brake 9 is released. This speed command value is normally zero.
The speed control unit A15 and the speed control unit B16 perform current control on the torque current command value iq ^* calculated by the subtracter 30 such that the difference between the rotational speed calculation value ω of the electric motor 5 and the speed command value ω ^* becomes zero. To the unit 19. In these speed control units A15 and B16, for example, P control, PI control, PID control, etc. are used. In order to increase the response speed of the control system, the speed control unit B16 has a control gain larger than that of the speed control unit A15. Yes.
In the current control unit 19, vector control is generally used. In the vector control, the motor current detected by the current detector 7 is converted into the d-axis and the q-axis, and the q-axis current that contributes to the torque of the motor 5 is controlled to coincide with the torque current command value iq ^* . As the command voltage at this time, the current control unit 19 outputs the voltage command values vd ^* and vq ^* of the electric motor 5 to the drive signal generation unit 13.

In the present invention, the brake control is switched to the speed control unit B16 before releasing the brake at the time of activation. Thereafter, brake braking is released by the brake control unit 20. For example, when an elevator start command (not shown) is input to the control state determination unit 17, the control state determination unit 17 operates the switching unit 18 to switch the speed control unit to the speed control unit B16. When the switching of the speed control unit is completed, the control state determination unit 17 sends an elevator start command to the brake control unit 20 and the brake control unit 20 releases the brake braking. Alternatively, an activation command may be input directly to the brake control unit 20 so that the brake control unit 20 delays the brake braking release for a time corresponding to the speed control unit switching processing time.
When the brake is released, an unbalance torque is applied to the motor 5 according to the unbalance amount between the car 11 and the counterweight 12, and the motor 5 is controlled by the speed control unit B16 so as to balance the unbalance torque. . At this time, the control state determination unit 17 monitors the control state by the speed control unit B16, determines whether the speed control has converged, and operates the switching unit 18 if it is determined that the speed control has converged. And switch to the speed control unit A15.
In this switching, the torque current command value iq ^* becomes discontinuous simply by switching the speed control unit, so that the torque current command value is smoothly connected. This is realized by adding an appropriate offset value to the output of the speed control unit A15 after switching so that the torque current command value is continuous before and after switching. Further, a filter process such as a primary filter may be performed on the torque current command value.
These processes include, for example, a function in which the speed control units A15 and B16 output a command value to which a desired offset value is added, or a function to output a command value obtained by performing a predetermined filter process on the output. Each function is executed in accordance with a control signal from the unit 17.

The control state determination unit 17 determines the convergence of the speed control based on the torque current command value iq ^* output from the speed control unit B16. Hereinafter, a method for determining convergence of speed control will be described with reference to FIG. 2A shows the motor speed, FIG. 2B shows the absolute value | iq ^* | of the torque current command value iq ^* , FIG. 2C shows the differential value of | iq ^* |, and FIG. The output switching trigger is shown. The reason why the absolute value | iq ^* | of the torque current command value iq ^* is used is that the sign of iq ^* differs depending on the direction of the unbalance torque, but it is not necessary to consider the sign by taking the absolute value, and the mounting is easy. It is to become.

First, when brake braking is released at time t1, a load corresponding to the unbalance torque between the car 11 and the counterweight 12 is applied to the electric motor 5, and the electric motor 5 starts to rotate. At this time, in order to make the rotation of the motor 5 zero, the motor torque is increased until the unbalanced torque is balanced by the speed control unit B16, so | iq ^* | increases. The torque current command value (| iq ^* |) becomes a constant value at time t2 when the unbalance torque and the motor torque are balanced.

In FIG. 2, the unbalance torque amount and the motor torque are balanced at time t2. The control state determination unit 17 determines that the speed control has converged when the torque current command value (| iq ^* |) becomes a constant value, and switches to the speed control unit A15. The determination | iq ^* | amount of change, that is | iq ^* | using a differential value of, when the differential value becomes the threshold Di1 below predetermined trigger switching control state determination unit 17 The data is output to the switching unit 18 and switched to the speed control unit A15. When the torque current command value (| iq ^* |) becomes a constant value, the differential value of | iq ^* | is ideally zero, but in reality, the torque current command value must contain a small variation. Therefore, the threshold value Di1 is set as a value close to zero considering the variation.

Since the differential value of | iq ^* | is equal to or less than Di1 immediately after the brake braking is released, the speed control convergence determination is not performed immediately after the brake braking is released (time t1). For example, the convergence determination may not be performed for a certain time immediately after the brake is released, or the convergence determination may be performed after | iq ^* | exceeds Di1.

Thus, by determining the state where the torque current command value iq ^* is constant, it is possible to accurately determine the convergence of the speed control regardless of the unbalance torque of the car and the counterweight. Therefore, even when the unbalance torque of the car and the counterweight is small, it is possible to quickly switch to the speed control unit A15 after the convergence of the speed control. Accordingly, since the speed control converges and the speed control unit B16 continues to operate in a very low speed state including the state where the car is held stationary, it is possible to avoid destabilizing the control system. The starting shock and rollback can be reduced regardless of the unbalance torque of the car and the counterweight.

In the present embodiment, the torque current command value iq ^* is used for speed control convergence determination in the control state determination unit 17, but the actual torque current value (torque current detection value) detected by the current detector 7 is used. Also good. Furthermore, the voltage command value vd ^* or vq ^* output from the current control unit 19 may be used in place of the torque current command value iq ^* to perform convergence determination based on comparison with the threshold value similar to the above method.

Embodiment 2. FIG.
FIG. 3 is a block diagram showing an elevator control apparatus according to Embodiment 2 of the present invention. In FIG. 3, the parts denoted by the same reference numerals as in the above embodiment basically operate in the same manner as in the above embodiment.

In this embodiment, the speed control convergence determination operation performed by the control state determination unit 317 is different from that of the first embodiment. In the present embodiment, the control state determination unit 317 determines the convergence of the speed control based on the signal from the speed / position detector 8. As a method, the speed / position detector 8 outputs a signal (pulse or voltage) corresponding to the rotation amount of the electric motor 5 as described above. The control state determination unit 317 counts an output change amount (for example, the number of pulses) per unit time of the output of the speed / position detector 8. When the absolute value of the change amount is equal to or less than a predetermined threshold, the control state determination unit 317 determines that the speed control has converged, and operates the switching unit 18 to move the speed control unit from the speed control unit B16. An operation of switching to the speed control unit A15 is performed. At this time, the control state determination unit 317 may count the output change from the speed / position detector 8 in a time period longer than the calculation period of the speed control unit B16.

When the car 11 is held stationary by speed control, the motor 5 vibrates slightly in the vicinity of zero speed. However, by making the calculation cycle for counting the output change amount longer than the calculation cycle of the speed control unit B16, Since the vibration is canceled and the output change amount of the speed / position detector 8 is nearly zero, the convergence determination of the speed control can be performed more stably.

As described above, in this embodiment, the convergence of the speed control is determined regardless of the unbalance torque of the car and the counterweight by determining the convergence of the speed control based on the output change amount of the speed / position detector 8. It is possible to quickly switch to the speed control unit A15 later. Therefore, it is possible to avoid that the speed control unit B16 continues to operate in a very low speed state including the state where the speed control is converged and the car is held stationary, and the control system becomes unstable. For this reason, the control response of the speed control unit B16 can be increased, and the starting shock and the rollback can be reduced regardless of the unbalance torque of the car and the counterweight.

Embodiment 3 FIG.
FIG. 4 is a block diagram showing an elevator control apparatus according to Embodiment 3 of the present invention. In FIG. 4, the parts denoted by the same reference numerals as in the above embodiment basically operate in the same manner as in the above embodiment. In the present embodiment, position control for controlling the rotational position of the electric motor 5 is performed in order to reduce the rollback and the start shock immediately after the brake braking is released. The configuration of this embodiment is a configuration in which a position control loop is added to the outside of the speed control loop, and includes a position control unit 430 and a position command generation unit 431. Further, the speed / position calculation unit 421 calculates the rotation speed ω and the rotation position (calculation value) θ of the electric motor 5 from the output of the speed / position detector 8. The speed / position detector 8 and the speed / position calculation unit 421 constitute a speed / position detection calculation unit. The speed / position detection calculation unit and the speed detection calculation unit including the speed / position detector 8 and the speed calculation unit 21 according to the above-described embodiment are referred to as an electric motor state detection calculation unit. The position command generator 431 outputs a position command value θ ^* obtained by converting the position command value of the elevator car 11 into the rotational position of the electric motor 5. When the elevator is started, a position command value for holding the car 11 stationary is output before the brake 9 is released. This position command value is normally zero.

The position control unit 430 calculates the speed command value ω ^* calculated by the subtractor 31 so that the difference between the rotational position calculation value θ of the electric motor 5 and the position command value θ ^* becomes zero. P control, PI control, PID control, etc. are used. The speed control unit A15 and the current control unit 19 perform the same operation as in the first embodiment, and the elevator is controlled.

Thereby, after the braking of the brake 9 is released, the control for reducing the rollback and the starting shock is performed. At this time, the control state determination unit 17 monitors the control state by the position control unit 430 and the speed control unit A15, determines whether or not the position control has converged, and if it is determined that the position control has converged, The output of the position / speed switching unit 18a is switched to the output of the speed command generating unit 14 in order to operate the speed switching unit 18a and switch from position control to speed control.

In this switching, since the speed command value ω ^* is discontinuous simply by switching, processing is performed in which the speed command value ω ^* is smoothly connected. This is realized by adding an appropriate offset value to the output of the speed command generator 14 after switching so that the speed command value is continuous before and after switching. Further, a filtering process such as a primary filter may be performed on the speed command value.
These processes include, for example, a function in which the speed command generation unit 14 outputs a command value to which a desired offset value is added, or a function to output a command value obtained by performing a predetermined filter process on the output, and a control state determination unit Each function is executed in accordance with a control signal from 17. The operation of the control state determination unit 17 is the same as the method described in the first embodiment.

As described above, in the present embodiment, since the convergence of the position control can be determined and the speed control can be promptly switched, the response (control gain) of the position control unit 430 can be increased. Regardless of the unbalance torque of the counterweight 12, the starting shock and rollback can be reduced stably.

In the present embodiment, the method of detecting the rotational position of the electric motor 5 has been described as the position control. Good. In addition to the configuration shown in FIG. 4 as the position control method, the configuration shown in FIG. 1 is used, and the configuration of the speed control unit B16 is added to the speed PI control, the speed command value ω ^* and the rotational speed ( It may be configured as a control unit to which a double integral of the difference of (calculation value) ω is added. In this case, the configuration becomes simpler than that of FIG. 3 and the amount of calculation can be reduced, so that a cheaper control device can be realized.

Further, this embodiment may be combined with the first embodiment. That is, as shown in FIG. 5, in addition to position control, the speed control portion includes a relatively high response speed control unit B16 and a relatively low response speed control unit A15 (speed control unit B16, speed control unit A15). (Which constitutes a speed control means), and a structure for switching from the speed control unit B16 to the speed control unit A15 at the timing of switching from position control to speed control. By adopting such a configuration, it is possible to further increase the response at the time of start-up, so that the start-up shock and the rollback can be further reduced.

Further, even if the control state determination unit 17 of the present embodiment is replaced with the control state determination unit 317 described in the second embodiment, the same effect can be obtained.
In combination with the above-described embodiment, the control state determination unit determines that the torque current command value iq ^* , the torque current detection value detected by the current detector 7, and the voltage command value (vd) to the inverter 4 for motor control. ^* Or vq ^* ), the amount of change is determined in advance based on at least one change amount of the rotation amount of the motor detected by the motor state detection calculation unit (which is set as the control state of the motor). It is determined that the position control and speed control have converged when the threshold value is below the threshold value. The same applies hereinafter.

Embodiment 4 FIG.
FIG. 6 is a block diagram showing an elevator control apparatus according to Embodiment 4 of the present invention. In FIG. 6, the parts denoted by the same reference numerals as in the above embodiment basically operate in the same manner as in the above embodiment. In the present invention, the operation of the control state determination unit 517 is different from that of the second embodiment. The present embodiment is characterized in that an appropriate one is selected from speed control units having a plurality of response speeds in accordance with the output change amount of the speed / position detector 8 immediately after the brake braking is released. FIG. 6 shows a case where two types of speed control units are provided, and the operation will be described below with reference to the flowchart of FIG.

First, in step S61, an elevator start command is received. The start command is input to at least the brake control unit 20 and the control state determination unit 517.
Next, in step S62, the brake control unit 20 releases the braking of the brake. At this time, the switching unit 18 is switched by the control state determination unit 517, and the speed control unit A15 and the speed control unit B16 are not operated, or one of the speed control unit A15 and the speed control unit B16 is selected. . Further, the speed command value ω ^* output from the speed command generator 14 is zero.
In step S63, the control state determination unit 517 calculates a change amount per unit time of the rotation amount of the electric motor 5 output from the speed / position detector 8.

In steps S64 to S66, the control state determination unit 517 selects an appropriate speed control unit based on the absolute value of the change amount. The amount of change depends on the unbalance torque of the car 11 and the counterweight 12 and the overall inertia of the elevator system. The amount of change increases when the overall inertia is small and when the unbalance torque is large. When the load capacity of the car 11 changes, the overall inertia and unbalance torque of the elevator system change. Generally, however, the change in the unbalance torque due to the change in the load capacity rather than the change in the overall inertia due to the change in the load capacity. Since the amount is more dominant than the movement at the time of start-up, that is, the amount of change per unit time of the speed / position detector 8, the amount is The balance torque can be estimated. Based on this idea, if the absolute value of the change amount of the speed / position detector 8 is equal to or smaller than a threshold value set in advance based on the dynamic characteristics of the elevator, it is determined that the unbalance torque is small, and the process proceeds to step S65. Part A15 is selected. If the absolute value of the change amount exceeds the threshold value, it is determined that the unbalance torque is large, the process proceeds to step S66, and the speed control unit B16 having a higher response speed than the speed control unit A15 is selected.

It should be noted that the threshold used in step S64 is appropriately set according to the state of the control system when the brake is released in step S62. That is, different values are set according to the case where the speed control is not operated or the type of the selected speed control unit. In general, when the response frequency of the speed control system is high, the amount of change per unit time of the speed / position detector 8 is smaller than when the response frequency is low and when the speed control system is not operated. Therefore, when the response frequency of the speed control system selected in step S62 (at the time of brake braking release) is high, the threshold used in step S64 is the case where the response frequency of the speed control system selected in step S62 is low. Compared to a small value.

If the speed control unit B16 is selected, it is determined in step S67 whether or not the unbalance torque compensation has been completed by the elevator control device and the speed control has converged. This can be determined using the method described in the second embodiment. If it is determined that the speed control has converged, the control is switched to the speed control unit A15 having a relatively low response speed in step S68.

As described above, in the present embodiment, the unbalance torque between the car 11 and the counterweight 12 is estimated based on the absolute value of the change amount of the speed / position detector 8 immediately after the brake braking is released, and the unbalance torque is small. It is possible to select the speed controller A15 having a normal response speed and select the speed controller B16 having a relatively high response speed when the unbalance torque is large. That is, the speed control unit B16 can be selected only when the unbalance torque required by the speed control unit B16 is large. Furthermore, when the speed control unit B16 is selected, it is possible to determine that the speed control has converged and to switch to the speed control unit A15 having a normal response speed.

As described above, since it is possible to avoid the speed control unit B16 from continuing to operate in a very low speed state including the state where the car is held stationary and destabilizing the control system, the control response of the speed control unit B16 can be increased. The start shock and rollback can be stably reduced regardless of the unbalance torque between the car 11 and the counterweight 12.

Note that the same effect as that of the present embodiment can be obtained by using the method described in the first embodiment instead of using the method described in the second embodiment as the method for determining the convergence of the speed control in step S67. Can do. At this time, the configuration of FIG. 6 is a configuration in which the torque current command value iq ^* is added to the control state determination unit 517 as an input.

In steps S63 and S64, the speed control unit is switched based on the amount of change per unit time of the speed / position detector 8, but the amount of change of the speed / position detector 8 is set in advance after brake braking is released. The speed control unit may be switched based on the elapsed time until reaching the reference value (for example, 1 to several pulses when the speed / position detector 8 is a pulse encoder). At this time, since the elapsed time becomes shorter as the unbalance torque becomes larger, when the elapsed time is smaller than a preset threshold, switching to the speed control unit B16 is performed, and in other cases, a normal response is performed. Switch to the speed controller A15.

In the present embodiment, a configuration having two types of speed control units with different response speeds (control gains) has been described, but a configuration having three or more types of speed control units may be used. At this time, in step S64, a speed control unit having an appropriate response speed is selected according to the absolute value of the change amount of the speed / position detector 8. At this time, if a speed control unit with a high response speed is selected, the operation proceeds to steps S67 and S68. By having three or more types of speed control units, the speed control unit can be selected more finely according to the unbalance torque, so that the start-up shock and rollback can be further reduced.

Embodiment 5. FIG.
FIG. 8 is a block diagram showing an elevator control apparatus according to Embodiment 5 of the present invention. In FIG. 8, the parts denoted by the same reference numerals as in the above embodiment basically operate in the same manner as in the above embodiment. In the present invention, the operation of the control state determination unit 717 is different from that of the first embodiment. The present embodiment is characterized in that an appropriate one is selected from speed control units having a plurality of response speeds according to the amount of change in the torque current command value iq ^* immediately after the brake braking is released. FIG. 8 shows a case where two types of speed control units are provided, and the operation will be described below with reference to the flowchart of FIG.

First, in step S81, an elevator start command is received. The start command is input to at least the brake control unit 20 and the control state determination unit 717.
Next, in step S82, the brake control unit 20 releases the braking of the brake. At this time, the switching state 18 is switched by the control state determination unit 717, and one of the speed control unit A15 and the speed control unit B16 is selected as the speed control. Further, the speed command value ω ^* output from the speed command generator 14 is zero.
Next, in step S83, the control state determination unit 717 calculates the amount of change per unit time of the torque current command value iq ^* output from either the speed control unit A15 or the speed control unit B16.

In steps S84 to S86, the control state determination unit 717 selects an appropriate speed control unit based on the absolute value of the change amount. The amount of change depends on the unbalance torque of the car 11 and the counterweight 12, and the amount of change increases as the unbalance torque increases. If the absolute value of the change amount of the torque current command value iq ^* is equal to or smaller than a preset threshold value, the unbalance torque is small, and the process proceeds to step S85, and the speed control unit A15 is selected. When the absolute value of the amount of change exceeds the threshold value, the unbalance torque is large, so that the process proceeds to step S86, and the speed control unit B16 having a higher response speed than the speed control unit A15 is selected.
Note that the threshold value used in step S84 is also appropriately set according to the state of the control system at the time of brake braking release in step S82. That is, the threshold value is set differently depending on the type of the speed control unit that is selected when the brake is released.

When the speed control unit B16 is selected, it is determined in step S87 whether or not the unbalance torque compensation has been completed by the elevator control device and the speed control has converged. This can be determined using the method described in the first embodiment. If it is determined that the speed control has converged, the control is switched to the speed control unit A15 having a low response speed in step S88.

As described above, in this embodiment, the unbalance torque between the car 11 and the counterweight 12 is estimated based on the absolute value of the change amount of the torque current command value iq ^* immediately after the brake braking is released. When the unbalance torque is large, the speed control unit B16 having a large response speed can be selected. That is, the speed control unit B16 can be selected only when the unbalance torque required by the speed control unit B16 is large. Furthermore, when the speed control unit B16 is selected, it is possible to determine that the speed control has converged and to switch to the speed control unit A15 having a normal response speed.

Note that the same effect as this embodiment can be obtained by using the method described in the second embodiment instead of using the method described in the first embodiment as a method for determining the convergence of the speed control in step S87. At this time, the configuration of FIG. 8 is a configuration in which the output of the speed / position detector 8 is added as an input of the control state determination unit 717.

In the present embodiment, a configuration having two types of speed control units with different response speeds (control gains) has been described, but a configuration having three or more types of speed control units may be used. At this time, in step S84, a speed control unit having an appropriate response speed is selected according to the absolute value of the change amount of the torque current command value iq ^* . At this time, if a speed control unit with a high response speed is selected, the operation proceeds to steps S87 and S88. By having three or more types of speed control units, it is possible to select the speed control unit more finely according to the unbalance torque, and therefore it is possible to further reduce the start shock and rollback.

It should be noted that the present invention is not limited to the above-described embodiments, and it is needless to say that all possible combinations of the embodiments are included.

For example, in combination with the above-described embodiment, the control state determination unit performs the torque current command value iq ^* , the torque current detection value detected by the current detector 7 immediately after the brake is released when the elevator is started, and the motor control. At least one change amount among the voltage command value (vd ^* or vq ^* ) to the inverter 4 of the motor, the rotation amount of the motor detected by the motor state detection calculation unit, and (this is the control state of the motor). Based on this, the speed controller is selected. Further, it is determined whether or not the speed control and the position control have converged by comparing each change amount with a predetermined threshold value.

Industrial applicability

The elevator control device according to the present invention can be applied to various traction type elevators.

4 inverter, 5 motor, 7 current detector, 8 speed / position detector, 9 brake, 14 speed command generator, 15 speed controller A, 16 speed controller B, 17, 317, 517, 717 control state determination unit , 18, 18a switching unit, 22 control device.

Claims

According to the control state and control convergence state of the motor control system at the start of the elevator, the response speed of the motor speed control is changed, or the position control of the motor is switched from the speed control to the speed control. An elevator control device comprising a control state determination unit that switches to control and changes a response speed of the speed control.
A motor state detection calculation unit that detects the rotation amount of the motor and calculates at least the rotation speed of the motor;
A speed command generator for generating a rotation speed command value of the motor;
A plurality of speed control units having different response speeds for controlling the rotation speed of the motor according to the output difference between the speed command generation unit and the motor state detection calculation unit;
A switching unit for switching the plurality of speed control units;
The control state determination unit that switches the plurality of speed control units by operating the switching unit according to the control state of the electric motor;
With
When the control state determination unit switches the switching unit to the speed control unit having a relatively large response speed when the elevator is started and determines that the speed control has converged according to the control state of the motor, the response speed is The elevator control device according to claim 1, wherein the elevator control device is switched to the relatively small speed control unit.
Instead of switching the switching unit to the speed control unit having a relatively large response speed when the elevator is started, the control state determination unit immediately after releasing the brake at the time of starting the elevator, a torque current command value and a torque current detection value The speed control unit is selected based on at least one change amount among a voltage command value for motor control and a rotation amount of the motor detected by the motor state detection calculation unit. The elevator control device described in 1.
A motor state detection calculation unit that detects the rotation amount of the motor and calculates the rotation speed and rotation position of the motor;
A position command generator for generating a rotational position command value of the electric motor;
A speed command generator for generating a rotation speed command value of the motor;
A position control unit that controls the rotational position of the electric motor according to an output difference between the position command generation unit and the electric motor state detection calculation unit;
Speed control means for controlling the rotational speed of the electric motor according to the output difference between the position control unit or the speed command generation unit and the electric motor state detection calculation unit;
A position / speed switching unit that switches to and inputs one of the output of the position control unit and the output of the speed command generation unit to the speed control unit;
The control state determination unit that switches the input to the speed control means by operating the switching unit according to the control state of the electric motor,
With
When the control state determination unit switches the input to the speed control unit to the output of the position control unit when the elevator is started and determines that the position control has converged according to the control state of the electric motor, the speed control unit The elevator control device according to claim 1, wherein the input to is switched to the output of the speed command generator.
The speed control means includes a plurality of speed control units with different response speeds, and the elevator control device further includes a switching unit that switches the plurality of speed control units,
When the control state determination unit operates the switching unit to switch to the speed control unit having a relatively high response speed when the elevator is started and determines that the position control has converged, the response speed is relatively small The elevator control device according to claim 4, wherein the elevator control device is switched to the speed control unit.
The control state determination unit is based on at least one change amount among a torque current command value, a torque current detection value, a voltage command value for motor control, and a rotation amount of the motor detected by the motor state detection calculation unit. 6. The elevator control device according to claim 1, wherein the control is determined to have converged when the change amount is equal to or less than a predetermined threshold value. 6.
Whether the control state determination unit changes the response speed of the motor speed control or switches from the position control of the motor to the speed control according to the control state of the motor control system and the convergence state of the control at the time of starting the elevator A method for controlling an elevator, comprising switching from position control to speed control and changing a response speed of the speed control.