CN118234675A

CN118234675A - Selection of the travel direction of an elevator car

Info

Publication number: CN118234675A
Application number: CN202180104224.5A
Authority: CN
Inventors: J·尼坎德; J-M·艾塔穆尔托; L·斯托尔特
Original assignee: Kone Corp
Current assignee: Kone Corp
Priority date: 2021-11-16
Filing date: 2021-11-16
Publication date: 2024-06-21
Also published as: EP4433404A1; WO2023088534A1

Abstract

The invention relates to a method for selecting a travel direction of an elevator car (110) for rescue driving, the method comprising: generating (210; 220) a first estimate and a second estimate of total energy consumption indicative of the travel of the elevator car (110) in a first direction and a second direction from its estimated position to the next landing (10); -comparing (230) the first estimate and the second estimate, and-selecting (240) a direction of travel for the rescue drive corresponding to the smaller of the first estimate and the second estimate. The invention also relates to an apparatus, an elevator system and a computer program for executing the apparatus, the elevator system.

Description

Selection of the travel direction of an elevator car

Technical Field

The present invention relates generally to the technical field of conveyor systems. More particularly, the present invention relates to elevator systems.

Background

Elevator service is interrupted due to a power failure of the elevator system. In a disadvantageous situation, the elevator car with passengers is stuck between two floors and it is necessary to solve this in some way, in particular if the power failure continues for a long time.

In some embodiments, the elevator system may be equipped with an energy storage, such as a battery, configured to store an amount of energy, allowing the elevator car to be transported to a floor under a so-called rescue drive operation. The size of the energy storages is optimized and the aim is to apply as small energy storages as possible in order to minimize their size and cost and to minimize their impact in the overall design of the elevator system.

In order to achieve an optimisation of the energy storage, it is necessary to introduce a novel method aimed at selecting the best path for the rescue drive at least partly taking into account the energy consumption.

Disclosure of Invention

The following presents a simplified summary in order to provide a basic understanding of some aspects of various inventive embodiments. This summary is not an extensive overview of the invention. It is intended to neither identify key or critical elements of the invention nor delineate the scope of the invention. The following summary merely presents some concepts of the invention in a simplified form as a prelude to the more detailed description of the exemplary embodiments of the invention.

The object of the invention is to propose a method, a device, an elevator system and a computer programme for selecting the direction of travel of an elevator car.

The object of the invention is achieved by a method, an arrangement, an elevator system and a computer program for selecting the direction of travel of an elevator car as defined by the respective independent claims.

According to a first aspect, there is provided a method for selecting a direction of travel of an elevator car for rescue drive, the method comprising:

a first estimate indicative of the total energy consumption of the elevator car traveling in a first direction from its estimated position to the next landing is generated by:

Determining an amount of energy required to move the elevator car in the first direction by controlling the elevator car to move a first reference distance in the first direction,

An amount of energy required to move the elevator car in the first direction from its estimated position to a next landing is estimated,

Adding the amount of energy required to move the elevator car in the first direction and the amount of energy required to move the elevator car from its estimated position to the next landing in the first direction to generate the first estimate,

A second estimate of total energy consumption indicating that the elevator car traveled from its estimated position to the next landing in a direction opposite to the first direction is generated by:

The amount of energy required to move the elevator car in a direction opposite the first direction is determined by controlling the elevator car to move a second reference distance in a direction opposite the first direction,

An amount of energy required to move the elevator car from its estimated position to a next landing in a direction opposite the first direction is estimated,

Adding the amount of energy required to move the elevator car in a direction opposite to the first direction and the amount of energy required to move the elevator car from its estimated position to the next landing in the direction opposite to the first direction to generate the second estimate,

Comparing the first estimate with the second estimate, and

A direction of travel for the rescue drive is selected that corresponds to the smaller of the first estimate and the second estimate.

The amount of energy required to cause movement of the first reference distance or movement of the second reference distance may be derived from data indicative of an input current of an electric motor configured to cause the respective movement.

Further, the estimated position of the elevator car may be determined based on at least one of: data indicative of the position of the elevator car obtained from at least one sensor; position data of the elevator car stored in a data memory. For example, the estimated position of the elevator car can be determined from the position data stored in the data storage by selecting a piece of data as the data of the estimated position most recently stored to the data storage before the event causing the rescue drive.

Estimating the amount of energy required to move the elevator car from its estimated position in said first direction to the next landing or in a direction opposite to the first direction can be performed by estimating the amount of energy required to generate torque to the traction sheave to move the elevator car in the corresponding direction.

The step of estimating the amount of energy required to move the elevator car from its estimated position to the next landing in the first direction or in a direction opposite to the first direction may comprise determining information indicative of a change in balance of the elevator system on a first path from the estimated position of the elevator car to the next landing in the first direction and on a second path from the estimated position of the elevator car to the next landing in the direction opposite to the first direction.

The method may further comprise:

determining an amount of energy available from an energy source for the rescue drive,

Determining whether an amount of energy available from the energy source for the rescue drive exceeds an estimate indicative of total energy consumption corresponding to a selected direction of travel, and

In response to detecting that the amount of energy available from the energy source for the rescue drive exceeds an estimate indicative of total energy consumption corresponding to the selected direction of travel, an indication is generated that allows for initiation of the rescue drive to the selected direction of travel.

Still further, the method may further comprise:

Determining a first peak power required for the elevator car to travel from its estimated position to the next landing in the first direction, and determining a second peak power required for the elevator car to travel from its estimated position to the next landing in a direction opposite to the first direction,

Comparing the determined first peak power and the determined second peak power with a reference value,

Upon detecting that the determined peak power of the same direction of travel as the selected direction of travel is below the reference value, confirming the direction of travel selected based on a comparison of the first and second estimates of the rescue drive,

When it is detected that the determined peak power for the same direction of travel as the selected direction of travel exceeds the reference value, the direction of travel selected based on a comparison of the first and second estimates for the rescue drive is prevented.

The selection of the direction of travel may comprise generating a control signal to the elevator drive such that a control signal to the electric motor is generated.

According to a second aspect, there is provided an apparatus for selecting a direction of travel of an elevator car for rescue drive, the apparatus being configured to:

Comparing the first estimate with the second estimate, and

The apparatus may be configured to derive from data indicative of an input current of an electric motor configured to cause a corresponding movement an amount of energy required to cause movement of the first reference distance or movement of the second reference distance.

The apparatus may be further configured to obtain an estimated position of the elevator car from at least one of: a sensor that generates data indicative of the position of the elevator car; a data memory configured to store position data of the elevator car. For example, the apparatus may be configured to determine the estimated position of the elevator car from the position data stored in the data storage by selecting one piece of data as the data of the estimated position most recently stored to the data storage before the event causing the rescue drive.

Furthermore, the arrangement may be configured to perform the estimation of the amount of energy required to move the elevator car from its estimated position in a first direction to the next landing or in a direction opposite to the first direction by estimating the amount of energy required to generate torque to the traction sheave to move the elevator car in the corresponding direction.

The apparatus may be configured to perform the step of estimating the amount of energy required to move the elevator car from its estimated position to the next landing in the first direction or in a direction opposite to the first direction by performing a determination of information indicative of a change in balance of the elevator system on a first path from the estimated position of the elevator car to the next landing in the first direction and on a second path from the estimated position of the elevator car to the next landing in a direction opposite to the first direction.

The apparatus may be further configured to:

Determining a first peak power required for the elevator car to travel from its estimated position to the next landing in the first direction and determining a second peak power required for the elevator car to travel from its estimated position to the next landing in a direction opposite to the first direction,

Upon detecting that the determined peak power for the same direction of travel as the selected direction of travel exceeds the reference value, the direction of travel selected based on a comparison of the first and second estimates for the rescue drive is prevented.

The apparatus may be configured to perform the selection of the direction of travel by generating a control signal to the elevator drive to generate a control signal to the electric motor.

According to a third aspect, there is provided an elevator system comprising an arrangement according to the second aspect as defined above.

According to a fourth aspect, there is provided a computer program comprising instructions which, when executed by a computer, cause the computer to perform a method according to the first aspect as defined above.

The expression "number" means herein any positive integer from the beginning, for example, to one, two or three.

The expression "plurality" herein refers to any positive integer starting from two, for example, to two, three or four.

Various exemplary and non-limiting embodiments of the present invention as to its construction and method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific exemplary and non-limiting embodiments when read in connection with the accompanying drawings.

The verbs "comprise" and "comprise" are used herein as open-ended limits and neither exclude nor require the presence of unrecited features. Features recited in the dependent claims may be freely combined with each other unless explicitly stated otherwise. Furthermore, it should be understood that the use of "a" or "an" throughout this document, i.e., in the singular, does not exclude a plurality.

Drawings

Embodiments of the invention are illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings.

Fig. 1 schematically illustrates an elevator system according to an example.

Fig. 2 schematically illustrates a method according to an example.

Fig. 3 schematically illustrates other aspects of a method according to an example.

Fig. 4 schematically shows an apparatus according to an example.

Detailed Description

The specific examples provided in the description given below should not be construed as limiting the scope and/or applicability of the appended claims. The list and set of examples provided in the description given below is not exhaustive unless explicitly stated otherwise.

Fig. 1 schematically illustrates an elevator system 1000 according to an exemplary embodiment, in which the functionality according to the invention may be implemented. An elevator system 1000 as disclosed in fig. 1 may include an elevator car 110, the elevator car 110 being arranged to move or movable in an elevator hoistway 120, e.g., along guide rails mounted in the elevator hoistway 120. Movement of the elevator car 110 may be achieved by means of hoisting ropes or belts 130 connected to a counterweight 140 on a traction sheave 150 or the like. Operation of the elevator system 1000 may be achieved by controlling the rotation of the traction sheave 150 with the electric motor 160 and the elevator brake 170. Further, the electric motor 160 may be controlled with a frequency converter 180, the frequency converter 180 being configured to provide an input current to the electric motor 160 to cause the electric motor 160 to operate in a controlled manner. Overall control of the elevator system can be performed by the apparatus 200 corresponding to e.g. an elevator controller, which receives feedback from other elevator entities, such as from call-giving devices etc., among other functions, in order to generate control signals to the frequency converter 180 based on the feedback.

For the purposes of describing at least some embodiments of the invention, the elevator system may also include a plurality of sensors 190 that reside, for example, in the elevator hoistway 120 and/or the elevator car 110. The sensor 190 may be of any type suitable for generating measurement data from which an estimate of the position of the elevator car 110 in the elevator hoistway 120 may be derived. The estimation of the position should be understood in a broad way and it may mean an accurate position or some inaccurate estimation of the position for the purpose of the invention, as discussed in the following description. Some non-limiting examples of sensors 190 suitable for generating measurement data indicative of the position of elevator car 110 may be hoistway-mounted contact sensors configured to mechanically, electrically, magnetically, or optically interact with a counterpart residing in elevator car 110 in response to elevator car 110 passing by the respective sensor 190. Alternatively or additionally, a plurality of sensors 190 may be mounted to the elevator system, for example to the electric motor 160. For example, measurement data may be obtained from the motor encoder, based on which an estimate of position may be determined. A non-limiting example of a sensor 190 associated with the elevator car 110 may be a barometer that provides measurement data indicative of pressures experienced at different locations in the elevator hoistway 120 from which an estimate may be generated. Any other sensor type may also be applied in the context of the invention to obtain measurement data that is directly or indirectly indicative of the position of the elevator car 110.

In normal operating conditions, the elevator system 1000 is powered by mains current. To ensure the supply of electricity to the elevator system 1000, the elevator system according to the invention can be equipped with an energy store 195, which can be arranged to supply electricity to the elevator system 1000 or at least to at least some entities of the elevator system 1000 in special situations, such as in an emergency. The energy storage 195 adapted to store electrical energy may be, for example, a battery implemented in any known manner. The supply of energy source 195 may be arranged such that the supply of electrical energy may be initiated automatically in response to detecting a failure of the supply of electrical power from mains, or may be arranged by implementing a predefined function on the energy storage or the elevator system in order to be able to supply energy at a predefined event. The supply of electrical energy can be arranged to the electrical network of the elevator system or only to the key entities of the elevator system in order to perform the method as described in the upcoming description. In fig. 1, the power supply is arranged through a frequency converter 180 such that at least the frequency converter 180 and the electric motor 160 are energized.

As already mentioned, the elevator system 1000 comprises a device 200 configured to perform at least part of the control operation of the elevator system 1000, wherein the device 200 may refer to an elevator controller. The apparatus 200 is communicatively connected to at least some entities of the elevator system 1000 for delivering control signals thereto and receiving data, such as sensor data, from the elevator system 1000. The apparatus 200 is at least configured to control operation of an elevator drive system that includes at least both the frequency converter 180 and the electric motor 160. The apparatus 200 is further arranged to receive power from the energy storage 195 in case of a power failure from mains. For completeness, it is understood that even though the apparatus 200 and the frequency converter 180 are described and shown in fig. 1 as separate entities and devices, their functionality may be integrated into a single device if convenient from an implementation point of view.

As is known, an elevator system is arranged to travel between a plurality of landings 10 or floors in order to transport passengers and any other loads between landings 10 served by the elevator system 1000. The energy consumption of the elevator system 1000 during a ride also depends on the so-called balancing of the elevator system 1000 in question. Balancing refers to the effect of the selection of the elevator car 110 and the corresponding counterweight 140 and the weight of the ropes 130 on both sides divided by the traction sheave 150. The elevator system 1000 may be balanced at a certain position of the elevator car 110 in the elevator hoistway 120, i.e. when the weights on both sides with respect to the traction sheave 150 are equal, i.e. even if the elevator brake is deactivated, the elevator car 110 does not move. On the other hand, from the perspective of the elevator car 110, the balancing situation may be over-balanced or under-balanced at some other location of the elevator car 110 in the elevator hoistway 120, as different portions of the ropes 130 on each side are separated by the traction sheave 150. An over-balanced condition refers to the elevator car 110 traveling downward if the elevator car 110 is allowed to move freely, and in an under-balanced condition the elevator car 110 traveling upward. Furthermore, the elevator system 1000 may be designed such that the system is in equilibrium only at one end of the travel path in the elevator hoistway 120, or even such that there is no location where the elevator system 1000 is in equilibrium. The balancing situation can be handled by means of so-called compensating ropes mounted under the elevator car 110 and the counterweight, respectively. By applying the compensating ropes, the amount of power required to move the system in various positions in the elevator hoistway can be operated in a known manner. Still further, in at least some elevator implementations, the effect of the weight of the elevator travelling cable may be considered when considering the balance with other items described above, i.e., the elevator car 130, counterweight 140, elevator ropes 130, and compensating ropes (if any).

The present invention provides a solution for selecting the best direction for rescue drive in the event that operation of elevator system 1000 ceases due to a power failure. A method according to an exemplary embodiment is schematically illustrated in fig. 2, wherein the method provides a solution for selecting the direction of travel of the elevator car 110 for rescue driving or the like. According to an example embodiment, the method may be performed by a computing unit (such as a controller), as described in the upcoming description. For example, the entity configured to perform at least a portion of the method may be the apparatus 200 configured to perform at least a portion of the control operations of the elevator system 1000. The method may be initiated by generating a first estimate 210 indicative of the total energy consumption to cause the elevator car 110 to travel from its estimated location to the next landing in a first direction and by generating a second estimate 220 indicative of the total energy consumption to cause the elevator car 110 to travel from its estimated location to the next landing in a direction opposite the first direction. In other words, the apparatus 200 may determine an estimated position of the elevator car 110 in the elevator hoistway 120 based on any applicable data that it may access, wherein the elevator car 110 is stopped due to a particular situation (such as due to a power failure). In response to knowing the estimated position of the elevator car 110, the apparatus 200 may be configured to generate a first estimate 210 indicative of the total energy consumption to cause the elevator car 110 to travel in a first direction from its estimated position to the next landing. Further, the apparatus 200 is configured to generate a second estimate indicative of the total energy consumption to cause the elevator car 110 to travel from its estimated position to the next landing in a direction opposite to the first direction. In other words, the apparatus 200 is configured to generate the first estimate and the second estimate by at least partly utilizing information about the estimated position of the elevator car 110. The term total energy consumption in the estimated context should be understood to cover a selected number of sources included in the generation of the total energy consumption, as described in the upcoming description. Furthermore, in the context of the elevator system 1000, the first direction and the second direction opposite to the first direction essentially refer to the vertical direction in which the elevator car 110 is arranged to travel in the elevator hoistway 120. For example, the first direction may be vertically upward and the second direction may be vertically downward, or vice versa. The generation of the first estimate 210 and the second estimate 220 may be performed at least partially simultaneously or subsequently to each other.

In response to generating 210, 220 the first estimate and the second estimate, the apparatus 200 is configured to compare 230 the first estimate and the second estimate together. The purpose of the comparison 230 is to determine the direction of travel of the elevator car 110 to the next landing, wherein the energy consumption of travel is minimized. For clarity, the comparison step 230 may be implemented such that the first estimate and the second estimate are compared together and information about the smaller one is obtained.

In response to the comparison 230, the apparatus 200 is arranged to select 240 a direction of travel of the rescue drive corresponding to the smaller of the first estimate and the second estimate. Thus, the apparatus 200 maintains information linking the total energy consumption to each direction and the corresponding direction of travel, and generates data indicative of the direction of travel as an output of the selecting step 240. For example, the apparatus 200 may be configured to generate control signals to a power generation device (such as to the frequency converter 180) to control an electric motor of the elevator system 1000 to cause the elevator car 110 to travel in a selected direction of travel in the elevator hoistway 120.

In the following description, further details are provided regarding generating estimates 210, 220 indicative of the total energy consumption for traveling the elevator car 110 from its estimated position to the next landing. The details provided herein and shown in fig. 3 apply to the generation of the first estimate 210 and the generation of the second estimate 220. According to the invention, the total energy consumption may consist of at least two aspects. For the first aspect, the amount of energy required to move the elevator car 110 in the selection direction is determined 310, and the determination is performed by controlling the elevator car 110 to move a reference distance in the selection direction. Further, a second aspect related to the total energy consumption according to an exemplary embodiment is estimating 320 the amount of energy required to move the elevator car 110 from its estimated position to the next landing in the selected direction. With respect to the first aspect and embodiments thereof, the apparatus 200 may be configured to generate a control signal to the power generation device to instruct the power generation device to generate a force to move the elevator car 110a reference distance in a selected direction, where the selected direction may be the first direction or the second direction first. In response to the elevator car 110 moving a reference distance in a first direction, the apparatus 200 may be configured to generate another control signal to the power generation apparatus to instruct the power generation apparatus to generate a force to move the elevator car 110 another reference distance in a second direction opposite the first direction. The movement of the reference distance in the second direction may start from a position where the elevator car 110 resides after the movement of the reference distance in the first direction, or the elevator car 110 may return to a starting position or reference position, i.e. to a position where the movement in the first direction is started, before the movement in the second direction is indicated. Advantageously, the selection of the starting point of the second direction is taken into account in the estimation of the energy consumption in a manner as described in the upcoming description. In other words, the elevator car 110 is caused to travel in two directions opposite to each other by a reference distance defined for the travel direction. The reference distances in the first direction and the second direction may be the same or different from each other. At least one purpose of movement of the elevator car 110 in the first and second directions is to determine how much energy is needed to initiate travel in the respective directions. As a non-limiting example, the reference distance may be a few centimeters, which allows determining the required energy, for example by deriving the required energy from data indicative of the input current of an electric motor configured to cause a force for a corresponding movement. For example, the derivation of the input current of the electric motor may be based on a measurement of one or more signal values indicative of the current and/or voltage applied in the elevator drive system. In other words, generally known equations may be applied to determine the required energy. Furthermore, the reference distance is advantageously small in order to avoid unnecessary energy consumption in the determined context.

Regarding the second aspect, an estimate 320 is made of the amount of energy required to move the elevator car 110 from its estimated position to the next landing. Such estimation is performed for the first direction and the second direction, respectively. The estimation may be performed mathematically, e.g. based on the estimated position of the elevator car 110 and its distance of travel in the first direction and the second direction to the next landing. Naturally, at least some parameters of the power generation device, such as the input current and the duration of time for which the input current is provided to reach the respective landing, may be applied. Alternatively or additionally, the estimation may be based on information obtained from the travel history of the elevator car 110, e.g. such that a corresponding section of the travel path from the elevator car 110 is determined, and the energy consumption for the respective section is determined and obtained in order to receive an estimate of the amount of energy required to move the elevator car 110 to the respective landing.

In response to the generation of the results from steps 310 and 320 for the first direction and the second direction as described, the apparatus 200 may be arranged to sum 330 the amount of energy required to move the elevator car to the selected direction and the amount of energy required to move the elevator car 110 from its estimated position to the next landing in the same selected direction to generate the corresponding estimate. For clarity, summation 330 is performed separately for the items determined in steps 310 and 320 with respect to the first direction and the second direction. Accordingly, the apparatus 200 may be configured to associate terms with respect to the direction of travel such that an estimate of the amount of energy required to travel the elevator car 110 in one direction and the amount of energy required to travel to the next landing in the same direction are added 330 to generate a first estimate and a second estimate for comparison 230.

In some exemplary embodiments of the invention, the determination of the estimated amount of energy required to move the elevator car 110 to the landing in question is performed by taking into account information indicating the balance of the elevator system 1000 at the location where the elevator car 110 resides. Furthermore, it is preferable to consider the balance information of the elevator system 1000 when traveling to the corresponding distance. This may be advantageous because the balance changes during travel because the mutual positions of the elevator car 110 and counterweight 140 change during operation. This is because the weight of the hoisting ropes 130 on both sides of the traction sheave 150 varies as the length of the ropes 130 varies in the respective sides. In other words, the balance may change during travel, which in turn may have an effect on the energy required to move the elevator car 110 to the corresponding landing.

As a non-limiting example, according to an embodiment, by mathematically estimating the energy required to produce the accumulated torque of the traction sheave 150 of the elevator over the distance from the position of the elevator car 110 to the landing in both directions, information about the balance can be taken into account when estimating the energy required to move the elevator car 110 in the first direction or the second direction from its estimated position to the next landing. The accumulated torque can be estimated mathematically by obtaining load information of the elevator car 110 (e.g. from weight sensors located in floors of the elevator car 110), the position of the elevator car 110 and the weight of any other relevant entity, such as a change in the weight of the elevator rope relative to the position of the elevator car 110 on both sides of the traction sheave 150 and a change in the weight of the compensating rope on both sides according to the position of the elevator car 110, and taking this information into account on the travel path to the evaluation direction to evaluate the accumulated torque and thus the energy consumption in both directions. For example, the energy required to generate the accumulated torque may be derived, for example, from the input current required to be supplied to the electric motor 160 to generate the accumulated torque to the traction sheave 150 as estimated. Of course, the same situation may be evaluated based on a control signal that may be generated by a drive system, such as frequency converter 180.

As disclosed in the foregoing description, the estimate of the amount of energy required to move the elevator car to the respective landing is based on the estimated position of the elevator car 110 in the elevator hoistway 120. The estimate of the position, i.e. the estimated position, may refer to an accurate position of the elevator car 110 or an estimate of a position with acceptable accuracy, such as at least knowing the landing between which the elevator car 110 resides. For example, the estimated position of the elevator car 110 may be obtained from a sensor configured to generate data indicative of the position of the elevator car 110 or from a data memory configured to store the position data of the elevator car 110. In the former case, power from the energy storage can be provided to the sensor to receive data indicative of the position of the elevator car 110, even during a power failure. In the latter case, the processing entity of the apparatus 200 may be configured to determine the estimated position of the elevator car 110 from the position data stored in the data memory. The determination may be performed by selecting the piece of data as the data of the estimated location most recently stored to the data storage prior to the event causing the rescue drive. Such a method is based on the arrangement: in response to a power failure, data input to the data store is canceled, and only data stored prior to the power failure or similar events can be found from the data store, and the last stored data fragment can be identified. For example, the stored data may originate from one or more sensors adapted to generate data indicative of the position of the elevator car 110, or may store data obtained from an electric motor (such as from an encoder thereof), based on which the position of the elevator car 110 may be determined. The data may e.g. indicate the position, speed or acceleration of the elevator car before the unexpected stop. Furthermore, the determination of the position of the elevator car 110 may take into account other data stored in the data memory and accessible therefrom, such as information about the deceleration of the elevator car 110 when the elevator car 110 is instructed to stop due to a specific situation (e.g. by applying an emergency stop mechanism). Thus, the distance travelled on deceleration can be determined and added to the latest known position to generate an estimate of the position. Additional aspects, such as the load of the elevator car 110, may also be considered for determining the distance of travel during deceleration prior to stopping. Alternatively or additionally, the estimation of the position of the elevator car 110 may further comprise the steps of: in embodiments where there is only information available about the last landing that the elevator car 110 passed before stopping, the accuracy of the estimation is improved by evaluating the time after the passage of the landing was detected and based thereon estimating how long the elevator car 110 may have traveled in the direction of travel during the determined time before stopping. Adding this distance to the location of the landing can generate an estimate of the location of elevator car 110. In summary, a position estimate with a predefined accuracy may provide the required information to determine a travel distance to a next landing in a first direction and another travel distance to the next landing in a second direction opposite to the first direction. Thus, in addition to estimating the position of elevator car 110, device 200 may also access data defining the position of the landing in a manner that may determine the distance traveled in any of the manners described.

The result of the method described so far is that the elevator car 110 should be directed in the direction of its movement in order to consume as little energy as possible, or at least less than moving the elevator car 110 in the opposite direction. The information about the direction is based on the generated estimate or estimate, which indicates the total energy consumption for the elevator car to travel from its estimated position to the corresponding landing. In view of this, embodiments of the present invention may include the further step of: an amount of energy available from the energy source 195 for rescue driving is determined, and then it is determined whether the amount of energy available from the energy source 195 exceeds an estimated value indicative of total energy consumption corresponding to the selected direction of travel. In response to detecting that the amount of energy available from energy source 195 for rescue drive exceeds an estimated value indicative of total energy consumption corresponding to the selected direction of travel, an indication is generated that allows for initiation of rescue drive to the selected direction of travel. This method is arranged to confirm that the elevator car 110 does arrive at the landing in the selected direction.

Furthermore, another aspect determined prior to the start of the rescue drive may be that the energy storage is capable of providing peak power that occurs at the end of the drive when starting movement and/or when braking the elevator car 110 to stop at the landing. This may be determined, for example, to enable the confirmation energy storage to provide the necessary current level to initiate travel and allow braking to establish the required peak power. More specifically, the method may be implemented such that the apparatus 200 configured to perform the method is configured to determine a first peak power required for the elevator car 110 to travel from its estimated position to the next landing in a first direction and to determine a second peak power required for the elevator car 110 to travel from its estimated position to the next landing in a direction opposite the first direction. The determination of the peak power can be performed separately such that the peak power required for starting the travel to the respective direction is determined, wherein the movement of the elevator car is controlled to determine a first estimate and a second estimate of the total energy consumption, as already described. The remaining portion of the required power may be estimated mathematically by taking into account the travel distance of the respective floor (e.g., estimating that the required power is linear over the travel distance) and estimating the power required to perform braking based on, for example, historical data or the like. By summing these terms, the peak power required in both directions can be estimated and determined. In response to the determination of peak power, each of them may be compared to a reference value. The reference value may depend on one or more characteristics of the energy source, i.e. its ability to provide power, and information about the reference value may be stored in a memory accessible to the device in order to obtain the reference value for comparison. When it is detected that the determined peak power of the same travel direction as the selected travel direction is lower than the reference value, a result of comparing the travel direction selected based on a comparison of the first and second estimates of the total energy consumption of the rescue drive may be confirmed. In other words, if the required peak power can be provided, the selection of the estimated travel direction based on the total energy consumption of the elevator car can be confirmed. On the other hand, if it is demonstrated in the comparison of the peak powers that the peak power determined based on the comparison of the first and second estimates of the rescue drive for the same direction of travel as the selected direction of travel exceeds the reference value, the direction of travel in question may be prevented. In other words, the direction of travel is prevented since the energy source cannot provide the necessary power throughout the entire travel even if the energy source stores enough energy for the corresponding travel. Of course, in the latter case, it is to be confirmed that another direction is possible in terms of power and energy consumption, so as to allow travel to that direction. For clarity, it is worth mentioning that the estimation of peak power and the conclusion based on the estimation as described herein may be performed at least partly simultaneously with the estimation of total energy consumption. Thus, at least one direction of travel may be prevented based on the peak power estimate before the selection of the direction of travel based on the total energy consumption is ended.

Still further, in some embodiments, the selection of the direction of travel may further include generating a control signal to the elevator drive such that a control signal to the electric motor is generated to activate the rescue drive.

For the sake of clarity, it is worth mentioning that a landing referred to as next landing in the first and second direction does not necessarily refer to the next physical landing, but is defined as a landing for rescue operations. Thus, the determination of the total energy consumption is performed with respect to those next stations.

An example of an apparatus 200 configurable to perform the described method is schematically shown in fig. 4. For clarity, it is worth mentioning that the block diagram of fig. 4 depicts some components of entities that may be used to implement the functionality of the apparatus 200. The apparatus 200 includes a processor 410 and a memory 420. Memory 420 may store data as described, but also computer program code 425 that causes secure operation in the manner described. The apparatus 200 may also include a communication interface 430, such as a wireless communication interface or a communication interface for wired communication, or both. Accordingly, communication interface 430 may include one or more modems, antennas, and any other hardware and software for enabling communications to be performed, for example, under the control of processor 410. Furthermore, an I/O (input/output) component may be arranged with the processor 410 and a portion of the computer program code 425 to provide a user interface for receiving input from a user (such as from a technician) and/or providing output to a user of the apparatus if necessary. In particular, the user I/O component may include a user input device such as one or more keys or buttons, a keyboard, a touch screen or pad, or the like. The user I/O component may include an output device such as a speaker, display, or touch screen. The components of the device may be communicatively connected to each other via a data bus that enables data and control information to be transferred between the components.

The memory 420 and a portion of the computer program code 425 stored therein may also be arranged, together with the processor 410, to cause the apparatus 200 to perform at least a portion of the method for selecting a direction of travel as described herein. The processor 410 may be configured to read from the memory 420 and write to the memory 420. Although the processor 410 is depicted as a respective single component, it may be implemented as a respective one or more separate processing components. Similarly, although memory 420 is depicted as a respective single component, it may be implemented as a respective one or more separate components, some or all of which may be integrated/removable and/or may provide permanent/semi-permanent/dynamic/cached storage.

The computer program code 425 may comprise computer executable instructions that, when the computer program code 425 is loaded into and executed in the processor 410 of the controller 210, implement the functions corresponding to the steps of the method. By way of example, computer program code 425 may comprise a computer program comprised of one or more sequences of one or more instructions. The processor 410 is capable of loading and executing a computer program by reading one or more sequences of one or more instructions contained therein from the memory 420. The one or more sequences of one or more instructions may be configured to, when executed by processor 410, cause apparatus 200 to perform a method as explicitly described in the description herein. Accordingly, the apparatus may include at least one processor 410 and at least one memory 420, the at least one memory 420 including computer program code 425 for one or more programs, the at least one memory 420 and the computer program code 425 configured to, with the at least one processor 410, cause the apparatus to perform the method.

Computer program code 425 may be provided, such as a computer program product, comprising at least one computer-readable non-transitory medium having computer program code 425 stored thereon, the computer program code 425 when executed by the processor 410 causing an apparatus to perform the method. The computer readable non-transitory medium may include a memory device or a recording medium, such as a CD-ROM, DVD, blu-ray disc, or another article of manufacture that tangibly embodies a computer program. As another example, a computer program may be provided as a signal configured to reliably transfer the computer program.

Still further, the computer program code 425 may include proprietary applications, such as computer program code for causing the method to be performed in a manner as described in the description herein.

Any of the programming functions mentioned may also be performed in firmware or hardware that is suitable or programmed to perform the necessary tasks.

The entity performing the method may also be implemented as a distributed computing environment by a plurality of devices, such as the devices schematically illustrated in fig. 4. For example, one of the devices may be communicatively connected with the other device and, for example, share data of the method to cause the other device to perform at least a portion of the method. Thus, the method performed in the distributed computing environment allows rescue operations to be performed in the elevator system 1000 in the manner described.

As described above, the apparatus 200 may be a predefined controller of the elevator system 1000, such as a master controller configured to control the overall operation of the elevator system 1000. The device 200 or devices 200 are advantageously arranged to automatically supply power from the energy store 195 in response to a power failure from mains, or it may be provided with their own energy store, in order to confirm that the device 200 is operable in any case, and to be able to perform the described method.

The specific examples provided in the description given above should not be construed as limiting the applicability and/or interpretation of the appended claims. The list and set of examples provided in the description given above is not exhaustive unless explicitly stated otherwise.

Claims

1. A method for selecting a travel direction of an elevator car (110) for rescue drive, the method comprising:

-generating (210) a first estimate of the total energy consumption indicating that the elevator car (110) travels in a first direction from its estimated position to the next landing (10) by:

Determining the amount of energy required to move the elevator car (110) in the first direction by controlling the elevator car (110) to move a first reference distance in the first direction,

Estimating an amount of energy required to move the elevator car (110) in the first direction from its estimated position to a next landing,

Adding the amount of energy required to move the elevator car (110) in the first direction and the amount of energy required to move the elevator car (110) in the first direction from its estimated position to the next landing (10) to generate the first estimate,

-Generating (220) a second estimate of the total energy consumption indicating that the elevator car (110) travels from its estimated position to the next landing (10) in a direction opposite to the first direction by:

determining the amount of energy required to move the elevator car (110) in a direction opposite to the first direction by controlling the elevator car (110) to move a second reference distance in a direction opposite to the first direction,

Estimating the amount of energy required to move the elevator car (110) from its estimated position to the next landing (10) in a direction opposite to the first direction,

Adding the amount of energy required to move the elevator car (110) in a direction opposite to the first direction and the amount of energy required to move the elevator car (110) from its estimated position to the next landing (10) in a direction opposite to the first direction to generate the second estimate,

Comparing (230) the first estimate and the second estimate, and

A direction of travel for the rescue drive is selected (240) corresponding to the smaller of the first estimate and the second estimate.

2. The method of claim 1, wherein the amount of energy required to cause movement of the first reference distance or movement of the second reference distance is derived from data indicative of an input current of an electric motor (160) configured to cause the respective movement.

3. The method of any of the preceding claims, wherein the estimated position of the elevator car (110) is determined based on at least one of: data indicative of the position of the elevator car (110) obtained from at least one sensor; -position data of the elevator car (110) stored in a data memory.

4. A method according to claim 3, wherein the estimated position of the elevator car (110) is determined from the position data stored in the data storage by selecting a piece of data as the data of the estimated position most recently stored to the data storage before the event causing the rescue drive.

5. The method according to any of the preceding claims, wherein estimating the amount of energy required to move the elevator car (110) from its estimated position in the first direction to the next landing (10) or in a direction opposite to the first direction to the next landing (10) is performed by estimating the amount of energy required to generate torque to the traction sheave to move the elevator car (110) in the respective direction.

6. The method of any of the preceding claims, wherein estimating the amount of energy required to move the elevator car (110) from its estimated position to the next landing (10) in the first direction or in a direction opposite to the first direction comprises determining information indicative of a change in balance of the elevator system (1000) on a first path from the estimated position of the elevator car (110) to the next landing (10) in the first direction and on a second path from the estimated position of the elevator car (110) to the next landing (10) in a direction opposite to the first direction.

7. The method of any of the preceding claims, the method further comprising:

Determining an amount of energy available from an energy source (195) for the rescue drive,

Determining whether an amount of energy available from the energy source (195) for the rescue drive exceeds an estimate indicative of total energy consumption corresponding to the selected direction of travel, and

In response to detecting that an amount of energy available from the energy source (195) for the rescue drive exceeds an estimate indicative of total energy consumption corresponding to the selected direction of travel, an indication is generated that allows for initiation of the rescue drive to the selected direction of travel.

8. The method of any of the preceding claims, the method further comprising:

Determining a first peak power required for the elevator car (110) to travel from its estimated position to the next landing in the first direction, and determining a second peak power required for the elevator car (110) to travel from its estimated position to the next landing in a direction opposite to the first direction,

9. The method of any of the preceding claims, wherein selecting a direction of travel comprises generating a control signal to an elevator drive to generate a control signal to the electric motor (160).

10. An apparatus (200) for selecting a travel direction of an elevator car (110) for rescue driving, the apparatus (200) being configured to:

Determining the amount of energy required to move the elevator car (110) in a direction opposite to the first direction by controlling the elevator car (110) to move a second reference distance in the direction opposite to the first direction,

Adding the amount of energy required to move the elevator car (110) in a direction opposite to the first direction and the amount of energy required to move the elevator car (110) from its estimated position to the next landing (10) in a direction opposite to the first direction to generate a second estimate, comparing (230) the first estimate and the second estimate, and

A direction of travel for rescue drive is selected (240) corresponding to the smaller of the first estimate and the second estimate.

11. The apparatus (200) of claim 10, wherein the apparatus (200) is configured to derive from data indicative of an input current of an electric motor (160) configured to cause a respective movement an amount of energy required to cause movement of the first reference distance or movement of the second reference distance.

12. The apparatus (200) of claim 10 or claim 11, wherein the apparatus (200) is configured to obtain the estimated position of the elevator car (110) from at least one of: a sensor that generates data indicative of a position of the elevator car (110); a data memory configured to store position data of the elevator car (110).

13. The apparatus (200) of claim 12, wherein the apparatus (200) is configured to determine the estimated position of the elevator car (110) from the position data stored in the data memory by selecting a piece of data as the data of the estimated position most recently stored to the data memory prior to the event causing the rescue drive.

14. The device (200) according to any one of claims 10 to 13, wherein the device (200) is configured to perform the estimation of the amount of energy required to move the elevator car (110) from its estimated position in the first direction to the next landing (10) or in a direction opposite to the first direction to the next landing (10) by estimating the energy required to generate torque to the traction sheave to move the elevator car (110) in the respective direction.

15. The apparatus (200) of any of claims 10 to 14, wherein the apparatus (200) is configured to perform the step of estimating the amount of energy required to move the elevator car (110) from its estimated position to the next landing (10) in the first direction or in a direction opposite to the first direction by performing a determination of information indicative of a change in balance of the elevator system (1000) on a first path from the estimated position of the elevator car (110) to the next landing (10) in the first direction and on a second path from the estimated position of the elevator car (110) to the next landing (10) in a direction opposite to the first direction.

16. The apparatus (200) according to any of the preceding claims 10 to 15, the apparatus (200) being further configured to:

17. The apparatus (200) of any one of claims 10 to 16, the apparatus (200) further configured to:

18. The apparatus (200) of any of claims 10-17, wherein the apparatus (200) is configured to perform the selection of the direction of travel by generating a control signal to an elevator drive to generate a control signal to the electric motor (160).

19. An elevator system (1000) comprising the apparatus according to any one of claims 10 to 18.

20. A computer program comprising instructions which, when executed by a computer, cause the computer to perform the method according to any one of claims 1 to 9.