The subject matter disclosed herein generally relates to the field of elevators, and more particularly to power distribution for a multicar, ropeless elevator system.
Ropeless elevator systems, also referred to as self-propelled elevator systems, are useful in certain applications (e.g., high rise buildings) where the mass of the ropes for a roped system is prohibitive and there is a desire for multiple elevator cars to travel in a single hoistway, elevator shaft, or lane. There exist ropeless elevator systems in which a first lane is designated for upward traveling elevator cars and a second lane is designated for downward traveling elevator cars. A transfer station at each end of the lane is used to move cars horizontally between the first lane and second lane.
According to one embodiment, an elevator power distribution system is provided. The system includes an elevator car configured to travel in a lane of an elevator shaft and a linear propulsion system configured to impart force to the elevator car. The linear propulsion system includes a first portion mounted in the lane of the elevator shaft and a second portion mounted to the elevator car configured to coact with the first portion to impart movement to the elevator car. A plurality of electrical buses are disposed within the lane and configured to provide power to the first portion of the linear propulsion system, a rectifier is electrically connected to each of the plurality of buses and configured to convert power provided between the respective bus and a grid, and a battery backup is electrically connected with the rectifier and configured to transfer power to or receive power from the rectifier.
In addition to one or more of the features described above, or as an alternative, further embodiments may include, wherein each of the plurality of buses is a continuous, uninterrupted power line extending the length of the lane.
In addition to one or more of the features described above, or as an alternative, further embodiments may include, wherein a plurality of pairs of rectifiers and battery backups are provided in electrical communication with each of the plurality of buses.
In addition to one or more of the features described above, or as an alternative, further embodiments may include one or more circuit breakers configured to split the continuous, uninterrupted power line into two or more zones.
In addition to one or more of the features described above, or as an alternative, further embodiments may include, wherein a single battery backup is configured in electrical communication with a plurality of rectifiers.
In addition to one or more of the features described above, or as an alternative, further embodiments may include, wherein each of the plurality of buses is composed of a plurality of zones.
In addition to one or more of the features described above, or as an alternative, further embodiments may include, wherein a plurality of pairs of rectifiers and battery backups are provided in electrical communication with each of the zones of the plurality of buses.
In addition to one or more of the features described above, or as an alternative, further embodiments may include, wherein each zone of the plurality of buses includes a single battery backup and a plurality of rectifiers in electrical communication therewith.
In addition to one or more of the features described above, or as an alternative, further embodiments may include one or more additional elevator cars, the power distribution system configured to supply power to and receive power from at least one of the elevator car and the one or more additional elevator cars.
In addition to one or more of the features described above, or as an alternative, further embodiments may include, wherein the plurality of buses is at least three buses.
According to another embodiment, a method of power distribution is provided. The method includes providing a plurality of buses configured to provide power to a linear propulsion system, converting power (i) received from a grid and providing it to at least one of the plurality of buses and (ii) received from at least one of the plurality of buses and providing to at least one of the grid and a battery backup, and transferring power from one of the plurality of buses to another of the plurality of buses to supply power thereto.
In addition to one or more of the features described above, or as an alternative, further embodiments may include, wherein each of the plurality of buses is a continuous, uninterrupted power line extending the length of the lane.
In addition to one or more of the features described above, or as an alternative, further embodiments may include, wherein a plurality of pairs of rectifiers and battery backups are provided in electrical communication with each of the plurality of buses.
In addition to one or more of the features described above, or as an alternative, further embodiments may include splitting the continuous, uninterrupted power line into two or more zones.
In addition to one or more of the features described above, or as an alternative, further embodiments may include, wherein each of the plurality of buses is composed of a plurality of zones.
In addition to one or more of the features described above, or as an alternative, further embodiments may include, wherein a plurality of pairs of rectifiers and battery backups are provided in electrical communication with each of the zones of the plurality of buses.
In addition to one or more of the features described above, or as an alternative, further embodiments may include, wherein each zone of the plurality of buses includes a single battery backup and a plurality of rectifiers in electrical communication therewith.
Technical features of the invention include providing a distributed power supply to a multicar, ropeless elevator system. Further technical features of embodiments of the invention include an efficient power distribution system with redundant power supply and control. Further technical features of embodiments of the invention include providing a battery backup system that enables self-sufficiency of a power supply system. Further technical features of embodiments of the invention include a redundant, distributive, and regenerative power distribution system.
The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:
As shown, above the top accessible floor of the building is an upper transfer station 130 configured to impart horizontal motion to the elevator cars 114 to move the elevator cars 114 between lanes 113, 115, and 117. It is understood that upper transfer station 130 may be located at the top floor, rather than above the top floor. Similarly, below the first floor of the building is a lower transfer station 132 configured to impart horizontal motion to the elevator cars 114 to move the elevator cars 114 between lanes 113, 115, and 117. It is understood that lower transfer station 132 may be located on the first floor, rather than below the first floor. Although not shown in
Elevator cars 114 are propelled within lanes 113, 115, 117 using a propulsion system such as a linear, permanent magnet motor system having a primary, fixed portion 116 and a secondary, moving portion 118. The primary portion 116 includes windings or coils mounted on a structural member 119, and may be mounted at one or both sides of the lanes 113, 115, and 117, relative to the elevator cars 114. Specifically, primary portions 116 will be located within the lanes 113, 115, 117, on walls or sides that do not include elevator doors.
The secondary portion 118 includes permanent magnets mounted to one or both sides of cars 114, i.e., on the same sides as the primary portion 116. The secondary portion 118 engages with the primary portion 116 to support and drive the elevators cars 114 within the lanes 113, 115, 117. Primary portion 116 is supplied with drive signals from one or more drive units 120 to control movement of elevator cars 114 in their respective lanes through the linear, permanent magnet motor system. The secondary portion 118 operatively connects with and electromagnetically operates with the primary portion 116 to be driven by the signals and electrical power. The driven secondary portion 118 enables the elevator cars 114 to move along the primary portion 116 and thus move within a lane 113, 115, and 117.
The primary portion 116, as shown in
Turning now to
In the example of
In some exemplary embodiments, as shown in
In order to drive the elevator car 214, one or more motor segments 222a, 222b, 222c, 222d can be configured to overlap the secondary portion 218 of the elevator car 214 at any given point in time. In the example of
Turning now to
In
AC power from the grid 302 is provided through power lines 304 to various service floors 360a, 360b, 360c and converted to DC power through rectifiers. As used herein, rectifies refers to any device configured to convert AC power to DC power. Thus, although the term rectifier is used throughout this description, those of skill in the art will appreciate that other configurations and/or device may be used without departing from the scope of the invention. Specifically, the term rectifier, as used herein, encompasses any device or process that converts AC power to DC power. As such, in some embodiments the rectifier may be configured as part of another device rather than a separate device, as shown in some of the embodiments disclosed herein.
Each service floor 360a, 360b, 360c has an associated set of rectifiers, such that rectifiers 361a, 362a, 363a, 364a are located on a first service floor 360a; rectifiers 361b, 362b, 363b, 364b are located on a second service floor 360b; and rectifiers 361c, 362c, 363c, 364c are located on a third service floor 360c. The set of rectifiers on each floor are provided for redundancy and fault management. Those of skill in the art will appreciate that although
The power distribution system 300 is configured with multiple DC buses per group of lanes (313, 315, 317). Thus, as shown in
Those of ordinary skill in the art will appreciate that the number of buses is variable, adjustable, or changeable, but typically the number of buses would need to be greater than one for adequate fault management and redundancy. To generate each DC bus 371, 372, 373, 374 an associated rectifier or group of rectifiers (as described above) is used and energy storage or battery backup 381a, 382a, 383a, 384a, etc., is attached to each rectifier to provide power when the grid fails or as other emergency and/or excess/additional power source and/or as a power storage medium/location. Each of the DC buses 371, 372, 373, 374 runs along the lanes 313, 315, 317 and various drives are connected to the DC bus, as described with respect to
Depending on the direction of movement of the elevator cars 314 the drives could be either sourcing or sinking power in to the DC bus system, e.g., if an elevator car 314 is moving downward and braking, power may be sourced and extracted from the system such as to recharge the associated backup battery (381a, 382a, 383a, 384a, etc.), or if the elevator car 314 is moving upward, power is provided to the associated bus from the grid or from battery backups. The presence of a continuous DC bus as shown in
The battery backup 381a, 382a, 383a, 384a, etc., as shown in
Turning now to
In embodiments that include zones or segments, power may be transferred between different buses and different zones. For example, in these configurations, power may be converted in rectifiers multiple times in order to reach the desired bus, battery backup, or location. Thus, embodiments configured with zones may operate substantially similar to the continuous bus configuration shown in
Turning now to
In the third embodiment, battery backups 585a, 585b, 585c are placed on the AC side of the rectifiers. The battery backups 585a, 585b, 585c are centralized and thus provide an energy sharing mechanism between various DC buses in a zone. The zoned DC bus scheme forces the regeneration energy from elevator car braking to be absorbed by the battery backup and zone-to-zone sharing occurs through the rectifiers. Advantageously, similar to the second embodiment, this zoned scheme may limit DC bus fault effects to a smaller section and contain feeder damage in the event of a fault. The presence of a centralized battery system, as shown in
In accordance with the various exemplary embodiments described above, the power control distribution described herein may be controlled by a central processor or computer. In some embodiments, the power distribution is controlled by a control system that operates and manages the entire elevator system. In some alternative embodiments, the power distribution control may be configured as a component that is separate from other controls for the elevator system.
Advantageously, various embodiments of the invention provide a reliable and efficient power distribution system for a multicar elevator system. In some embodiments, the presence of multiple DC buses enables fault management, redundancy, and continued operation in the event of a drive or DC bus failure. In some embodiments, the use of battery backups enables the system to safely stop elevator cars in an emergency situation, such as when building power loss occurs. In some embodiments, the zoned DC bus system limits the fault current from a DC bus short circuit failure to a limited area, e.g., to a single zone or segment. The zoning configurations enable the rest of the system to work during a fault of one bus or system component with no loss in performance. In some embodiments, with centralized battery storage, the sharing of energy from one zone to another zone is efficiently managed. In view of the above, advantageously, embodiments of the invention provide a safe and efficient power distribution system for a multicar elevator system.
Further, advantageously, because of the multiple bus configuration, regardless of a zoned or continuous bus configuration, the system can be configured to be substantially and/or essentially self-sufficient. For example, with the use of battery backups and regenerative braking and power storage in the battery backups, the system can rely on the power provided from these two sources and operate completely independently from the grid. Further, advantageously, because of the use of multiple buses, regenerative braking may provide excess energy and/or power that could be fed back to the grid, used to drive and/or power other elevator cars within the system, power other portions of the building, and/or be stored within the battery backup systems of the power distribution system.
Moreover, advantageously, embodiments of the invention provide a distributed, redundant, and regenerative power distribution system that is efficient and safe.
While the invention has been described in detail in connection with only a limited number of embodiments, it should be readily understood that the invention is not limited to such disclosed embodiments. Rather, the invention can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the invention. Additionally, while various embodiments of the invention have been described, it is to be understood that aspects of the invention may include only some of the described embodiments and/or features.
For example, although described herein as a conversion from AC to DC power for driving elevator cars, those of skill in the art will appreciate that AC power may be used, and battery backup systems may still be employed in accordance with embodiments of the invention. Further, in some embodiments, the service floors described herein that provide the power distribution systems of the invention may be located approximately every 20 floors within a building. However, those of skill in the art will appreciate that the distribution and configuration of these systems may vary and the floor distribution is not limiting herein. Further, although described with respect to application at service floors within a building, this is merely provided for exemplary and explanatory purposes and those of skill in the art will appreciate that the systems may be employed on any floor of a building, without departing from the scope of the invention.
Further, although described herein with four buses, and at each floor four rectifiers, with potentially four associated battery backups, those skilled in the art will appreciated that these numbers are not limiting and any number and configuration of the various component parts of the invention may be used without departing from the scope of the invention. Further, although described herein as the first embodiment having a continuous bus and the other embodiments having segmented buses, those of skill in the art will appreciate that known mechanisms are available such that a building configured with a single continuous bus system could have electrical components included to create a segmented or zoned configuration.
Accordingly, the invention is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.
Filing Document | Filing Date | Country | Kind |
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PCT/US2016/013831 | 1/19/2016 | WO | 00 |
Number | Date | Country | |
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62105989 | Jan 2015 | US |