HK1237327B - Elevator control apparatus and method for controlling an elevator group - Google Patents

Description

Elevator control device and method for controlling an elevator group

Technical Field

The invention relates to route determination for an elevator group comprising at least two elevators.

Background Art

When controlling an elevator group consisting of at least two elevators, determining the optimal solution for routing the elevators is a constant challenge. One possibility for optimizing routing is to minimize the total energy consumption of the elevator group. However, due to other parameters that are relevant to routing, the route with the lowest energy consumption may not be the best route when considering these other parameters.

Summary of the Invention

According to a first aspect of the present invention, an elevator control apparatus is provided, comprising at least one processor and at least one memory, the at least one memory including computer program code for one or more programs. The at least one memory and the computer program code operate in conjunction with the at least one processor to cause the apparatus to: control an elevator group comprising at least a first elevator and a second elevator, wherein the counterweight balance of the first elevator differs from the counterweight balance of the second elevator; determine a threshold load for each elevator in an up or down direction, respectively, the threshold load being dependent on the counterweight balance of the respective elevators and being a load at which energy consumed per up or down operation is approximately zero; and, when allocating an elevator in response to a destination call, control route determination for the first and second elevators, including minimizing a load difference from the threshold load.

In one embodiment, the threshold loads determine a preferred maximum load in the upward direction and a preferred minimum load in the downward direction.

In one embodiment, the at least one memory and computer program code operate with the at least one processor to cause the apparatus to: control route determination so that in an upward direction, the load of the assigned elevator is below a load threshold of the assigned elevator for the upward direction.

In one embodiment, the at least one memory and computer program code operating with the at least one processor cause the apparatus to: control route determination so that in a downward direction, the load of the assigned elevator is above a load threshold for the assigned elevator for the downward direction.

In one embodiment, the at least one memory and computer program code operate with the at least one processor to cause the apparatus to: consider the threshold load as a refinement term in route determination in order to prevent energy-inefficient route determination.

According to a second aspect of the present invention, there is provided an elevator system comprising a plurality of elevators, the plurality of elevators comprising at least a first elevator and a second elevator, wherein the counterweight balance of the first elevator is different from the counterweight balance of the second elevator; and an elevator control device according to any one of claims 1 to 5.

According to a third aspect of the present invention, a method for controlling an elevator group is provided, the elevator group including at least a first elevator and a second elevator, wherein the counterweight balance of the first elevator differs from the counterweight balance of the second elevator. The method comprises controlling the elevator group including at least the first elevator and the second elevator; determining a threshold load for each elevator in an up/down direction, respectively, the threshold load being dependent on the counterweight balance of the respective elevators and being a load at which energy consumed per up/down operation is approximately zero; and, when allocating the elevators in response to a destination call, controlling route determination for the first and second elevators, including minimizing a load difference from the threshold load.

In one embodiment, the threshold loads determine a preferred maximum load in the upward direction and a preferred minimum load in the downward direction.

In one embodiment, when assigning an elevator in response to a destination call, controlling route determination for the first and second elevators by minimizing a load difference from a threshold load that causes energy consumption includes controlling route determination so that in an upward direction, the load of the assigned elevator is below a load threshold for the assigned elevator for the upward direction.

In one embodiment, when assigning an elevator in response to a destination call, controlling route determination for the first and second elevators by minimizing a load difference from a threshold load that causes energy consumption includes controlling route determination so that in a downward direction, the load of the assigned elevator is above a load threshold for the assigned elevator for the downward direction.

In one embodiment, the method further comprises considering a threshold load as a refinement term in the route determination in order to prevent energy inefficient route determination.

According to a fourth aspect of the present invention there is provided a computer program comprising program code which, when executed by a processor, performs the method of the third aspect.

In one embodiment, the computer program is embodied on a computer readable medium.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are included to provide a further understanding of the invention and constitute a part of this specification, illustrate embodiments of the invention and together with the description help to explain the principles of the invention. In the drawings:

FIG1 is a flow chart illustrating a method according to an embodiment of the present invention.

FIG. 2 is a block diagram illustrating an elevator system according to one embodiment of the present invention.

FIG3 is a block diagram illustrating an elevator control apparatus according to an embodiment of the present invention.

DETAILED DESCRIPTION

FIG1 is a flow chart illustrating a method according to one embodiment of the present invention. FIG1 will be discussed in conjunction with FIG2. The method disclosed in FIG1 is arranged to control route determination for a first elevator 202 and a second elevator 210. FIG2 provides a simplified example that discloses only two elevator shafts 200 and 208 and two elevator cars 202 and 210 forming an elevator group.

Each elevator is associated with a counterweight. The counterweight 204 associated with the first elevator car 202 has a different counterweight balance than the counterweight 212 associated with the second elevator car 210.

In step 100 , an elevator group including at least a first elevator 202 and a second elevator 210 is controlled.

In step 102, a threshold load is determined for each elevator, first elevator 202, and second elevator 210, for each elevator's up/down direction. The threshold load depends on the counterweight balance of the corresponding elevator. The threshold load is determined as a load at which the energy consumed for each up/down movement is approximately zero. For example, if first counterweight balance 204 is 40%, the threshold load for the upward direction is, for example, 25% of the rated load. For the downward direction, if first counterweight balance 204 is 40%, the threshold load for the downward direction is, for example, 55% of the rated load. The threshold load can be proportional to the counterweight balance. Thus, for example, if second counterweight balance 212 is 60%, the threshold load for the upward direction is, for example, 45% of the rated load. For the downward direction, if second counterweight balance 212 is 60%, the threshold load for the downward direction is, for example, 75% of the rated load.

In step 104, when assigning elevators in response to a destination call, routing for the first elevator 202 and the second elevator 210 is controlled so that the loads of the first elevator 202 and the second elevator 210 are minimized from a threshold load.

The method disclosed above may not always provide the most energy-efficient route. However, based on this method, poor route determination can be avoided. In addition, when the load of the first elevator 202 and the second elevator 210 is minimized from a threshold load, energy consumption can be greater than zero, but at the same time, it can enable the selection of a route that optimizes other route optimization parameters besides energy consumption.

In one embodiment, the threshold load of the elevator (in other words, the threshold load in the upward direction and the threshold load in the downward direction) is determined as a load at which the energy consumed per up and down operation is approximately zero when the elevator is driven from the lowest floor to the highest floor and back from the highest floor to the lowest floor.

In one embodiment, the threshold loads determine a preferred maximum load in the upward direction and a preferred minimum load in the downward direction.

In one embodiment, when assigning elevators in response to a destination call, controlling the routing of first elevator 202 and second elevator 210 includes minimizing the load difference from a threshold load that causes energy consumption. In another example, a limit can be determined as to how much the load can deviate from the threshold load before causing energy consumption. This limit can be determined separately for each elevator and each direction.

In one example, route determination is controlled so that, in the upward direction, the load of the assigned elevator is below a load threshold for the assigned elevator for the upward direction. This achieves a solution with energy consumption less than or equal to zero. In another example, route determination is controlled so that, in the downward direction, the load of the assigned elevator is above a load threshold for the assigned elevator for the downward direction. This also achieves a solution with energy consumption less than or equal to zero. In another example, route determination is controlled so that, in the upward direction, the load of the assigned elevator is below a load threshold for the assigned elevator for the upward direction, and in the downward direction, the load of the assigned elevator is above a load threshold for the assigned elevator for the downward direction.

In one embodiment, the threshold load is taken into account in the route determination as a refinement term in order to prevent energy-inefficient route determination. This can be achieved by taking the threshold load into account in the cost function when calculating the route (in other words, when allocating elevators) by using a specific coefficient for the threshold load.

FIG3 is a block diagram illustrating an elevator control device 300 according to one embodiment of the present invention. The elevator control device 300 includes a processor 302 connected to a memory 304. The elevator control device 300 may also include multiple processors or memories. The memory 304 or multiple memories may include at least one computer program that, when executed by the processor 302 or multiple processors, causes the elevator control device 300 to perform programmed functions.

The exemplary embodiments of the present invention may be included in any suitable device, for example, any suitable server, workstation, PC, laptop computer capable of executing the processes of the exemplary embodiments and capable of communicating via one or more interface mechanisms. The exemplary embodiments may also store information related to the various processes described herein.

It should be understood that the exemplary embodiments are for illustrative purposes only, as many variations of the specific hardware used to implement the exemplary embodiments are possible, as will be understood by those skilled in the art of hardware. For example, the functionality of one or more components of the exemplary embodiments may be implemented via one or more hardware devices or one or more software entities (e.g., modules).

As described above, components of the exemplary embodiments may include computer-readable media or memory for maintaining data structures, tables, records, and/or other data described herein in accordance with the teachings of the present invention. Computer-readable media may include any suitable medium that participates in providing instructions to a processor for execution. Such media may take many forms, including but not limited to non-volatile media, volatile media, transmission media, and the like.

While the invention has been described in connection with a number of exemplary embodiments and implementations, the invention is not limited thereto but covers various modifications and equivalent arrangements falling within the purview of the possible claims.

Furthermore, the embodiments of the present invention described herein may be used in any combination with one another. Several embodiments may be combined together to form another embodiment of the present invention.

It is obvious to a person skilled in the art that, as technology advances, the basic idea of the invention can be implemented in various ways. Therefore, the invention and its embodiments are not limited to the examples described above, but they may vary within the scope of the claims.

Claims (12)

1. An elevator control device (300), comprising: At least one processor (302); and At least one memory (304) including computer program code for one or more programs, the at least one memory (304) and the computer program code operating together with the at least one processor (302) such that the device (300): The control includes an elevator group comprising at least a first elevator (202) and a second elevator (210); wherein the counterweight balance of the first elevator (202) is different from the counterweight balance of the second elevator (210); For each elevator, a threshold load is determined for the first elevator (202) and the second elevator (210) in the vertical direction. The threshold load depends on the counterweight balance of the corresponding elevator and is a load in which the energy consumption of each vertical run is approximately zero; and When an elevator is assigned in response to a destination call, the route determination for the first elevator (202) and the second elevator (210) is controlled by minimizing the load difference between the first elevator (202) and the second elevator (210) and the threshold load. 2. The elevator control device according to claim 1, wherein the threshold load determines a preferred maximum load in the upward direction and a preferred minimum load in the downward direction. 3. The elevator control device according to any one of claims 1 to 2, wherein the at least one memory (304) and the computer program code operate together with the at least one processor (302) such that the device (300): The control route is determined such that, in the upward direction, the load assigned to the elevator is lower than the assigned load threshold for the upward direction. 4. The elevator control device according to any one of claims 1 to 2, wherein the at least one memory (304) and the computer program code operate together with the at least one processor (302) such that the device (300): The control route is determined such that, in the downward direction, the load assigned to the elevator is higher than the assigned load threshold for the downward direction. 5. The elevator control device according to any one of claims 1 to 2, wherein the at least one memory (304) and the computer program code operate together with the at least one processor (302) such that the device (300): Threshold load is considered as a fine-grained term in route determination to prevent energy-inefficient route determination. 6. An elevator system, comprising: A plurality of elevators (202, 210) including at least a first elevator (202) and a second elevator (210), wherein the counterweight balance of the first elevator (202) is different from the counterweight balance of the second elevator (210); and The elevator control device (300) according to any one of claims 1 to 5. 7. A method for controlling an elevator group comprising at least a first elevator (202) and a second elevator (210), wherein the counterweight balance of the first elevator (202) is different from the counterweight balance of the second elevator (210), the method comprising: Control of an elevator group including at least the first elevator (202) and the second elevator (210); For each elevator, a threshold load is determined for the first elevator (202) and the second elevator (210) in the vertical direction. The threshold load depends on the counterweight balance of the corresponding elevator and is a load in which the energy consumption of each vertical run is approximately zero; and When an elevator is assigned in response to a destination call, the control for route determination for the first elevator (202) and the second elevator (210) includes minimizing the load difference with the threshold load. 8. The method of claim 7, wherein the threshold load determines a preferred maximum load in the upward direction and a preferred minimum load in the downward direction. 9. The method according to any one of claims 7 to 8, wherein, when allocating an elevator in response to a destination call, route determination for the first elevator (202) and the second elevator (210) by minimizing the load difference with respect to a threshold load causing energy consumption comprises: The control route is determined such that, in the upward direction, the load assigned to the elevator is lower than the assigned load threshold for the upward direction. 10. The method according to any one of claims 7 to 8, wherein, when allocating an elevator in response to a destination call, controlling the route determination for the first elevator (202) and the second elevator (210) by minimizing the load difference with respect to a threshold load comprises: The control route is determined such that, in the downward direction, the load assigned to the elevator is higher than the assigned load threshold for the downward direction. 11. The method according to any one of claims 7 to 8, further comprising: Threshold load is considered as a fine-grained term in route determination to prevent energy-inefficient route determination. 12. A computer-readable medium having a computer program thereon storing program code that, when executed by a processor, performs the method according to any one of claims 7 to 11.