WO2018003014A1

WO2018003014A1 - Elevator system

Info

Publication number: WO2018003014A1
Application number: PCT/JP2016/069128
Authority: WO
Inventors: 一文平林
Original assignee: 三菱電機株式会社
Priority date: 2016-06-28
Filing date: 2016-06-28
Publication date: 2018-01-04

Abstract

This elevator system has a plurality of elevators, a group management device that allots elevators for calls, and a service life estimation unit. The service life estimation unit estimates changes in the temperature of at least one inverter being monitored from among inverters, and estimates the remaining service life of the inverter being monitored on the basis of the estimated changes in temperature. The group management device compares a remaining service life estimated value obtained from the service life estimation unit with a remaining service life threshold value. If there is detected a service-life-approaching inverter that is an inverter for which the remaining service life estimated value is less than the remaining service life threshold value, the group management device suppresses the allotment of designated elevator cars, which are elevator cars corresponding to the service-life-approaching inverter, said allotment being suppressed to a greater extent than before the detection of the service-life-approaching inverter.

Description

Elevator system

This invention relates to an elevator system in which the operation of a plurality of elevator cars is managed by a group management device.

In the conventional elevator control device, the estimated value of the heat generation temperature change width of the power module for each car traveling pattern is registered in advance in association with the car traveling pattern. Based on the driving command from the main control unit, the life judgment unit accumulates the number of heat generations within the heat generation temperature change range corresponding to the car traveling pattern, and whether the power module has reached the life based on the accumulated number of heat generations Determine.

The heat generation temperature change width includes an element temperature change width (ΔTj) that is a temperature change width of a semiconductor element of the power module and a case temperature change width (ΔTc) that is a temperature change width of the case of the power module. . The life determination unit determines whether the power module has reached the life using both the estimated value of the element temperature change width and the estimated value of the case temperature change width.

Furthermore, in the life determination unit, the allowable number of heat generations for each heat generation temperature change width based on the life characteristics of the power module is registered in advance in association with the heat generation temperature change width. Then, the life determination unit calculates a thermal fatigue degree that is a ratio of the accumulated number of heat generations to the allowable number of heat generations, calculates an elapsed period from a preset determination start reference time to a thermal fatigue level calculation time, Based on the rate of increase in the degree of thermal fatigue during the elapsed period, the life reaching time of the power module is predicted.

When it is determined by the life determination unit that the power module has reached the life, the main control unit lowers the acceleration and deceleration of the car from the acceleration and deceleration of the car during normal operation, respectively (for example, Patent Document 1). reference).

International Publication No. 2008/078377

In the conventional elevator control apparatus as described above, if it is determined that the power module has reached the end of its service life, the acceleration and deceleration of the car are simply reduced, so the serviceability to the user is reduced. Further, simply reducing the acceleration and deceleration of the car may cause a failure of the power module that has reached the end of its life, further reducing serviceability.

The present invention has been made to solve the above-described problems, and provides an elevator system that can prevent deterioration of serviceability when the remaining life of the inverter is shortened while preventing failure of the inverter. The purpose is to obtain.

The elevator system according to the present invention includes a car, a counterweight, a hoist that raises and lowers the car and the counterweight, an inverter that supplies electric power to the hoist, and controls the inverter to operate a corresponding car. Estimated and estimated temperature changes of the monitored inverter that is at least one of a plurality of elevators each having an operation control unit that controls the elevator, a group management device that assigns elevators to calls, and inverters A life estimation unit that estimates the remaining life of the monitored inverter based on the temperature change is provided, and the group management device compares the remaining life estimation value obtained from the life estimation unit with the remaining life threshold value, and the remaining life estimation value is When a life approaching inverter that is an inverter that has fallen below the life threshold is detected, the allocation of the restrained car that is the car corresponding to the life approaching inverter is determined as approaching the life. Converter of the pre-detection suppress than.
The elevator system according to the present invention includes a car, a counterweight, a hoisting machine that raises and lowers the car and the counterweight, an inverter that supplies power to the hoisting machine, and an inverter that controls the corresponding car. A plurality of elevators each having an operation control unit that controls the operation of the group, a group management device that assigns elevators to calls, and a temperature change of a monitored inverter that is at least two of the inverters, A life estimation unit that estimates the remaining life of the inverter to be monitored based on the estimated temperature change is provided, and the group management device compares the remaining life estimation values obtained from the life estimation unit and compares the remaining life estimation values relative to each other. If a difference greater than the life difference threshold occurs, the inverter with the smaller estimated remaining life is made the life approaching inverter, and the restraint pair that is a car corresponding to the life approaching inverter is used. The assignment of the car, the service life approaching inverter detected prior to suppress than.

In the elevator system according to the present invention, the allocation of the car corresponding to the life approaching inverter is suppressed by the group management device more than before the detection of the life approaching inverter, so that the remaining life of some inverters can be prevented while preventing the failure of the inverter. Even when the system becomes shorter, it is possible to suppress a decrease in serviceability of the entire system.

It is a block diagram which mainly shows the elevator system by Embodiment 1 of this invention with a block. It is a block diagram which shows the function of the lifetime estimation part of FIG. It is a flowchart which shows operation | movement of the temperature determination part of FIG. It is a flowchart which shows operation | movement of the remaining life calculation part of FIG.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.
Embodiment 1 FIG.
FIG. 1 is a block diagram mainly showing blocks of an elevator system according to Embodiment 1 of the present invention. The elevator system according to the first embodiment includes first to

third elevators

100, 200, and 300, and a group management device 400 that manages these

elevators

100, 200, and 300 as a group. Although the configurations of the second and

third elevators

200 and 300 are omitted in FIG. 1, they are the same as the configuration of the first elevator 100. The group management device 400 selects and assigns one of the

elevators

100, 200, and 300 to the call.

In each of the

elevators

100, 200, and 300, the car 1 and the counterweight 2 are suspended in the hoistway by the suspension body 3 and are raised and lowered by the driving force of the hoisting machine 4. As the suspension body 3, a plurality of ropes or a plurality of belts are used.

The hoisting machine 4 includes a drive sheave 5, a hoisting machine motor 6 that rotates the driving sheave 5, a hoisting machine brake (not shown) that brakes the rotation of the driving sheave 5, and the rotational speed of the hoisting machine motor 6. It has a speed detector 7 for detecting the magnetic pole position. The suspension body 3 is wound around the drive sheave 5. For example, an encoder or a resolver is used as the speed detector 7.

The hoisting motor 6 is supplied with power from the power source 10 via the converter 8 and the inverter 9. Converter 8 converts an alternating voltage from power supply 10 into a direct voltage. The inverter 9 generates an alternating current having an arbitrary voltage and frequency from the direct-current voltage generated by the converter 8. Moreover, the inverter 9 produces an alternating current by switching a direct current voltage.

Between the power supply 10 and the converter 8, a main contactor (main power supply contactor) 11 for cutting off the power supply from the power supply 10 is provided. A smoothing capacitor 12 that smoothes the DC output from the converter 8 is connected between the converter 8 and the inverter 9. The value of the current supplied from the inverter 9 to the hoisting machine motor 6 is detected by the current detector 13.

The rotation angle information from the speed detector 7 and the motor current information from the current detector 13 are input to the elevator control device 20. The elevator control device 20 also receives a main contactor state signal indicating the open / closed state of the main contactor 11.

The elevator control device 20 has an operation control unit 21 and a life estimation unit 22. The operation control unit 21 controls the operation of the car 1 by controlling the inverter 9. Information on the target travel floor is sent from the group management device 400 to the elevator control device 20 of the

elevator

100, 200 or 300 assigned by the group management device 400.

The operation control unit 21 generates a speed command for the car 1, that is, a speed command for the hoisting machine 4 in response to the call registration. Further, the operation control unit 21 calculates a torque value based on the generated speed command and information from the speed detector 7 so as to make the rotational speed of the hoisting machine motor 6 coincide with the value of the speed command. Generate directives.

Further, the operation control unit 21 controls the inverter 9 based on the generated torque command and the motor current information from the current detector 13. Specifically, the operation control unit 21 converts the torque command into a current command value, and outputs a signal for driving the inverter 9 so that the current value detected by the current detector 13 matches the current command value. .

Vector control is used for current control of the inverter 9 by the operation control unit 21. That is, the operation control unit 21 detects the current command value converted from the torque command, the current value of the hoisting motor 6 detected by the current detector 13 and the magnetic pole position (rotational position) detected by the speed detector 7. Accordingly, the voltage value to be output by the inverter 9 is calculated, and an ON / OFF switching pattern is output to the transistor incorporated in the inverter 9.

The life estimation unit 22 estimates the temperature change of the inverter 9 (for example, estimates the square of the motor current through a first-order lag filter), and estimates the remaining life of the inverter 9 based on the estimated temperature change. In addition, the life estimation unit 22 sends information on the estimated remaining life value to the group management apparatus 400.

In the first embodiment, the life estimation unit 22 is provided in each of the first to

third elevators

100, 200, and 300. In the first to

third elevators

100, 200, and 300, the remaining life of the inverter 9 is monitored. That is, in the first embodiment, the inverters 9 of all the

elevators

100, 200, 300 are monitoring target inverters.

In the group management device 400, a remaining life threshold is set in advance. The group management apparatus 400 compares the remaining life estimated value obtained from the life estimating unit 22 with the remaining life threshold. When the life approaching inverter that is the inverter 9 whose remaining life estimated value is lower than the remaining life threshold value is detected, the group management apparatus 400 assigns the suppression target car that is the car 1 corresponding to the life approaching inverter to the lifespan. Suppress than before detection of approaching inverter (restriction of vehicle allocation).

Specifically, the group management device 400 mainly assigns at least one of short run traveling and balance road traveling to the car to be suppressed. Short run travel is travel where the travel distance per travel is less than or equal to the travel distance threshold (for example, the first floor or the second floor). Further, the balance road traveling is traveling on a balance road in which the load on the car 1 side is equal (or substantially equal) to that of the counterweight 2 side. It is preferable that at least one of short-run traveling and balance road traveling is assigned to the car to be restrained, and other traveling is assigned to other cars.

These short-run traveling and balance road traveling are traveling in which the motor current does not flow as much as possible. In addition, the occurrence of short run and balance road travel is performed by the group management device 400 by using a system (destination forecast system) that registers the destination floor at the landing or the entrance of the building before the user gets on the car 1. It can be grasped in advance.

In addition, when a new call occurs, the group management device 400 assigns a priority from the non-suppressed units if there is a unit that is not a suppression target in the standby state. Furthermore, the group management device 400 assigns the suppression target unit with priority on the operating efficiency of the elevator system when a call other than the short run traveling and the balance load traveling occurs when only the suppression target unit is in the standby state. However, it is preferable to assign another unit.

Also, when there is an inverter that is near the end of life, the group management device 400 informs maintenance personnel which inverter 9 is nearing the end of its life. As a notification method, a method of displaying or making an announcement on a maintenance tool (maintenance computer) can be mentioned. Further, the CPU board may recognize that the life of the inverter 9 is approaching. That is, it may be forcibly displayed that the life of the inverter 9 is approaching, using a display unit such as a 7-segment LED mounted on a processor board that performs various processes.

The remaining life threshold is set so that the life approaching inverter can be extended until the next periodic inspection time of the inverter 9 (for example, once a month) by suppressing the allocation of the cars to be suppressed. After the power module of the life approaching inverter is replaced, when a reset operation is performed by maintenance personnel, the remaining life estimation value is returned to the initial value by the life estimation unit 22 corresponding to the inverter 9.

The operation control unit 21 and the life estimation unit 22 can be configured by a common computer or separate computers. Further, the group management device 400 can also be configured by a computer independent from the elevator control device 20.

FIG. 2 is a block diagram showing functions of the life estimation unit 22 of FIG. The life estimation unit 22 includes a coordinate conversion unit 23, a temperature estimation unit 24, a temperature determination unit 25, and a remaining life calculation unit 26. The rotation angle information from the speed detector 7 and the motor current information from the current detector 13 are input to the coordinate conversion unit 23. The coordinate conversion unit 23 performs dq conversion on the input current value and outputs it to the temperature estimation unit 24.

The temperature estimation unit 24 estimates the temperature of the inverter 9 based on the information input from the coordinate conversion unit 23 and outputs the temperature estimation value to the temperature determination unit 25. The temperature determination unit 25 stores the following three temperature estimated values.
a: Estimated temperature value at the start of the N-th run b: Maximum temperature estimate value at the N-th run c: Estimated temperature value at the start of the N + 1th run

Also, the temperature determination unit 25 stores bc as a temperature difference when a> c. If a ≦ c, ba is stored as a temperature difference. The stored temperature difference is defined as ΔTc (N). Note that temperature fluctuation occurs during one run, but the fluctuation is approximately ignored.

Furthermore, a main contactor state signal is input to the temperature determination unit 25, and the temperature determination unit 25 detects activation / deactivation based on ON / OFF of the main contactor 11.

FIG. 3 is a flowchart showing the operation of the temperature determination unit 25 of FIG. The temperature determination unit 25 first checks whether or not the state of the main contactor 11 is ON (step S1). If the state of the main contactor 11 is ON, that is, if the hoisting motor 6 is activated, it is confirmed whether or not the activation flag is already ON (step S2).

If the start flag is not ON, it is determined that the hoisting motor 6 is immediately after starting, and the temperature estimated value (Tcf) immediately after starting is stored (step S3). Thereafter, the temperature estimated value (Tcf) immediately after the current start-up is compared with the temperature estimated value (Tcfb) immediately after the start-up previously stored (during operation), and whether Tcf ≧ Tcfb is satisfied. Is determined (step S4).

When Tcf ≧ Tcfb holds (when the above a ≦ c), a value obtained by subtracting Tcfb from the maximum temperature estimated value Tcmax during the previous run (above) is set to ΔTc (step S5). When Tcf <Tcfb (when a> c described above), a value obtained by subtracting Tcf from Tcmax (above bc) is set to ΔTc (step S6).

Δ After ΔTc at the time of the previous operation is determined, Tcmax is cleared (step S7), the activation flag is turned on (step S8), and the processing of that time is finished.

If the activation flag is ON in step S2, the temperature estimated value while the main contactor 11 is ON is constantly monitored, the maximum value (Tcmax) is stored (step S9), and the process is terminated. .

Further, if the state of the main contactor 11 is OFF in step S1, the temperature estimated value immediately after the start before one run is updated (step S10). Then, Tcmax is latched (step S11), the activation flag is cleared (step S12), and the process for that time is finished. The temperature determination unit 25 executes the operation of FIG. 3 at a predetermined cycle.

Next, a method for calculating the remaining life by the remaining life calculation unit 26 will be described. In general, it is known that a power module has a linear characteristic (ΔTc−power cycle life characteristic) where ΔTc (logarithm) is on the horizontal axis and life cycle (logarithm) is on the vertical axis. Therefore, it can be estimated from the ΔTc-power cycle life characteristic how many times the power module of the inverter 9 reaches the life (running).

The life estimation unit 22 holds the above life characteristics as a table. Then, the remaining life calculation unit 26 takes the reciprocal of the number of times until the service life is reached and subtracts it from the service life set value K (set for each product). For example, when the power cycle life LS (N) when ΔTc = 50 [deg] is 8 · 10 ⁵ , the remaining life estimated value Kz (N) = Kz (N−1) −1 / LS (N) is calculated. The calculation results are stored sequentially. In addition, the life set value K is set using an assumed start-up frequency, an assumed life, temperature data collected during development, and the like.

FIG. 4 is a flowchart showing the operation of the remaining life calculation unit 26 of FIG. The remaining life calculation unit 26 first confirms whether or not a reset operation after replacement has been performed by a reset operation by a maintenance worker (step S21). If the reset operation is being performed, the remaining life estimated value Kz is returned to the initial value Kz0 (step S22), and the process for that time is terminated.

If the reset operation is not performed, ΔTc output from the temperature determination unit 25 is input (step S23). Then, the life cycle number LS is calculated from the table of ΔTc-power cycle life characteristics (step S24). Thereafter, the remaining life estimated value Kz (N) is obtained by the above formula (step S25), and the process is terminated.

In such an elevator system, the group management device 400 suppresses the allocation of the car 1 corresponding to the life approaching inverter more than before the detection of the life approaching inverter, so that some inverters can be prevented while preventing the inverter 9 from malfunctioning. Even when the remaining life of 9 is shortened, it is possible to suppress a decrease in serviceability of the entire system.

At this time, the allocation to other cars will increase as the allocation to the car to be suppressed decreases. However, in normal group management, it is unlikely that the remaining lives of the inverters 9 of all the units will be shortened almost evenly. For this reason, even if some inverters 9 are determined to be near-life inverters, there is a high possibility that the remaining inverters 9 have a sufficient remaining life, and vehicle allocation is suppressed while utilizing the near-life inverters until the next replacement timing. It is possible to operate around the units that are not.

Thus, by suppressing the deterioration of serviceability in the entire bank, the capacity of the inverter 9 can be reduced and the cost can be reduced.

In addition, the remaining life threshold is set so that the life approaching inverter can be extended until the period of periodic inspection of the inverter 9 by suppressing the allocation of the cars to be suppressed, so that the power module can be more reliably damaged before being replaced. Can be prevented.

Furthermore, since the group management device 400 mainly assigns short run and balance load travel to the car to be restrained, the burden on the life approaching inverter is more reliably reduced while continuing to use the car to be restrained, and the life approaching. An inverter failure can be prevented.

Furthermore, since the group management device 400 informs the maintenance staff that there is a life approaching inverter, it is possible to more reliably prevent the life approaching inverter from failing.

In the first embodiment, all inverters 9 are monitored inverters. However, it is not always necessary to monitor the remaining lifetime of all inverters 9. For example, if only the elevator inverter that is preferentially used in group management is set as the monitoring target inverter, and the remaining life of the monitoring target inverter is shortened due to preferential use, it is possible to preferentially use another elevator.
In the first embodiment, only one remaining life threshold value is set. However, two or more remaining life threshold values may be set, and different vehicle allocation suppression may be performed according to the remaining life threshold level.

Embodiment 2. FIG.
Next, an elevator system according to Embodiment 2 of the present invention will be described. The configuration of the elevator system according to the second embodiment and how to obtain the estimated remaining life are the same as those in the first embodiment. In the group management apparatus 400 of the second embodiment, a relative life difference threshold value is set. The group management device 400 compares the remaining life estimation values obtained from the life estimation unit 22. And when the difference more than a relative life difference threshold value generate | occur | produces between remaining life estimated values, the group management apparatus 400 makes an inverter with a smaller remaining life estimated value a life approaching inverter. Other configurations and control methods are the same as those in the first embodiment.

As described above, the remaining life of the inverters 9 of the

elevators

100, 200, and 300 in the same bank may be grasped, and vehicle allocation may be suppressed for the car 1 corresponding to the inverter 9 having a relatively short remaining life. The same effects as those of the first embodiment can be obtained.

In the system according to the second embodiment, it is not always necessary to monitor the remaining lifetime of all inverters 9. However, since the remaining life estimated values are compared, at least two inverters 9 need to be monitored inverters.
In the second embodiment, only one relative life difference threshold value is set. However, two or more relative life difference threshold values may be set, and different vehicle placement restraints may be implemented according to the level of the relative life difference threshold value. .

Furthermore, both controls of the first and second embodiments may be performed simultaneously. In other words, while monitoring the relative difference in the estimated remaining life value, a comparison with the absolute remaining life threshold value is performed. If it falls below, you may suppress vehicle allocation.

Furthermore, in the first and second embodiments, short run traveling and balance road traveling are shown as methods of restraining vehicle allocation, but the present invention is not limited to these, and for example, a method of simply reducing (thinning out) the allocation frequency. There may be.
In the first and second embodiments, the group management device 400 notifies that there is a life approaching inverter, but notifies the life estimation unit 22 or notifies both the group management device 400 and the life estimation unit 22. May be.
Further, the life estimation unit 22 may be configured with an analog circuit.
Furthermore, in the first and second embodiments, the life estimation unit 22 is provided in the elevator control device 20, but may be provided separately from the elevator control device 20 or provided in the group management device 400.
The number of elevators managed by the group management apparatus 400 may be any number as long as it is two or more.

Claims

A car, a counterweight, a hoist that raises and lowers the car and the counterweight, an inverter that supplies power to the hoist, and controls the inverter to control the operation of the corresponding car A plurality of elevators each having an operation control unit;
A group management device that assigns the elevator to a call, and estimates a temperature change of a monitored inverter that is at least one of the inverters, and estimates a remaining life of the monitored inverter based on the estimated temperature change With a life estimation unit
The group management device compares the remaining life estimated value obtained from the life estimation unit with a remaining life threshold, and when a life approaching inverter that is an inverter in which the remaining life estimated value falls below the remaining life threshold is detected. The elevator system which suppresses allocation of the control object car which is a car corresponding to the said life approaching inverter rather than the detection before the said life approaching inverter.
2. The elevator system according to claim 1, wherein the remaining life threshold is set so that the life approaching inverter can be extended until a periodic inspection time of the inverter by suppressing allocation of the car to be suppressed.
A car, a counterweight, a hoist that raises and lowers the car and the counterweight, an inverter that supplies power to the hoist, and controls the inverter to control the operation of the corresponding car A plurality of elevators each having an operation control unit;
A group management device that assigns the elevator to a call, and estimates a temperature change of a monitored inverter that is at least two of the inverters, and estimates a remaining life of the monitored inverter based on the estimated temperature change With a life estimation unit
The group management device compares the remaining lifetime estimated values obtained from the lifetime estimating unit, and if a difference equal to or greater than a relative lifetime difference threshold occurs between the remaining lifetime estimated values, the inverter having the smaller remaining lifetime estimated value Is a life approaching inverter, and an elevator system that restrains assignment of a car to be restrained corresponding to the life approaching inverter more than before detection of the life approaching inverter.
The elevator according to any one of claims 1 to 3, wherein the group management device mainly assigns a short-run traveling whose traveling distance per traveling is equal to or less than a traveling distance threshold to the car to be suppressed. system.
The elevator system according to any one of claims 1 to 4, wherein the group management device assigns mainly traveling on a balance road to the car to be suppressed.
The elevator system according to any one of claims 1 to 5, wherein at least one of the group management device and the life estimation unit notifies the maintenance staff of the presence of the life approaching inverter. .