Patent · US10554102B2 · B2 · US

Method for operating a long stator linear motor

(11) Publication number

US10554102B2

(21) Application number

15/608,081

(22) Filing date

2017-05-30

(30) Priority date

2016-05-31

(43) Publication date

2020-02-04

(45) Date of grant

2020-02-04

(51) IPC

B60L 13/10; B60L 15/00; B60L 15/38; B65G 54/02; H02K 11/30; H02K 41/02; H02K 41/03

(52) CPC

H02K Dynamo-electric machines: 11/30, 41/02, 41/03, 41/031, 41/033
B60L Propulsion of electrically-propelled vehicles; supplying electric power for auxiliary equipment of electrically-propelled vehicles; electrodynamic brake systems for vehicles in general; magnetic suspension or levitation for vehicles; monitoring operating variables of electrically-propelled vehicles; electric safety devices for electrically-propelled vehicles: 13/10, 15/005, 15/38, 2240/429
B65G Transport or storage devices, e.g. conveyors for loading or tipping, shop conveyor systems or pneumatic tube conveyors: 54/02
G05B Control or regulating systems in general; functional elements of such systems; monitoring or testing arrangements for such systems or elements: 13/02, 13/021, 13/024
H02P Control or regulation of electric motors, electric generators or dynamo-electric converters; controlling transformers, reactors or choke coils: 25/06
Y02T Climate change mitigation technologies related to transportation: 10/64

(73) Assignee

B&R Industrial Automation GmbH

(72) Inventors

Andreas Weber; Joachim WEISSBACHER

(54) Title

Method for operating a long stator linear motor

(57) Abstract

In order to improve the adaptation of a long stator linear motor to requirements or conditions of individual transport units or of the transport track it is foreseen, that the control variables (StG) of a driving coil (7, 8) of long stator linear motor are superimposed with an excitation signal (AS) with a predetermined frequency band, wherein actual variables (IG) of the driving coil control are determined, from the control variables (StGAS) superimposed with the excitation signal (AS) and from the determined actual variables (IG) a frequency response is determined and from the frequency response the control parameters (RP) for this transport unit (Tx) are determined and the transport unit (Tx) is controlled using these determined control parameters (RP) for movement along the transport track.

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Claims (19)

A method for operating a long stator linear motor by moving at least one transport unit along at least one transport track having plural successively arranged driving coils arranged along the at least one transport track, the method comprising: controlling each of the plural successively arranged driving coils with a driving coil controller, wherein, during the controlling: the driving coil controller sets control variables (StG) for driving coils of the plural successively arranged driving coils that interact with the at least one transport unit; the control variables (StG) of at least one of the driving coils are superimposed with an excitation signal (AS) having a predetermined frequency band; actual variables (IG) are determined; a frequency response is determined from control variables (StGAS) superimposed with the excitation signal (AS) and the actual variables (IG); first control parameters (RP) of the driving coil controller are determined from the frequency response for the at least one transport unit; and movement of the at least one transport unit along the at least one transport track is controlled utilizing the first control parameters (RP).
The method of claim 1, wherein the control parameters (RP) are varied in order to set a predetermined property of the frequency response.
The method of claim 1, wherein the first control parameters (RP) control another different transport unit.
The method of claim 1, further comprising determining second control parameters (RP) for the other different transport unit.
The method of claim 4, wherein the driving coil controller utilizes the first or second control parameters (RP) for controlling movement of the at least one transport unit on different transport sections of the at least one transport track.
The method of claim 1, further comprising determining the control parameters (RP) at predetermined intervals.
The method of claim 1, further comprising determining the control parameters (RP) for different loading conditions of the at least one transport unit.
The method of claim 7, further comprising: determining, from the frequency response, a mass of a load carried by the at least one transport unit (Tx); and selecting corresponding control parameters (RP) based on the mass.
The method of claim 8, wherein the determining is repeated at predetermined intervals.
The method of claim 1, further comprising: first determining, from the frequency response, resonance and anti-resonance frequencies (f R, f AR); and second determining, based on a phase passing frequency (f D) of frequency response, if the resonance and anti-resonance frequencies (f R, f AR) are attenuated.
The method of claim 10, wherein the first determining is repeated at predetermined intervals.
The method of claim 1, further comprising: utilizing a predetermined movement profile for the at least one transport unit; utilizing parameter estimation; collecting a system parameter value over time; and determining, from a variation of the system parameter value over time, a wear condition of the at least one transport unit.
The method of claim 1, further comprising: utilizing a predetermined movement profile for the at least one transport unit; moving the at least one transport unit according to the predetermined movement profile; utilizing parameter estimation to determine at least one system parameter value of a model of the control system; collecting the at least one system parameter value over time; and determining, from a variation of the at least one system parameter value over time, a wear condition of the at least one transport track or of the at least one transport unit.
The method of claim 13, further comprising: determining a set stator current (i A) for at least one driving coil of the plural successively arranged driving coils; utilizing the model of the control system when calculating a stator current of the at least one driving coil; and minimizing an error between the determined set stator current (i A) and the calculated stator current by varying the at least one system parameter value of the model of the control system.
The method of claim 1, further comprising: implementing a pilot control that acts on an input of the driving coil controller.
The method of claim 15, wherein the driving coil controller comprises: a speed controller with a speed input; and a pilot control that calculates a speed pilot control (v vs), wherein the speed pilot control (v vs) acts on the speed input.
The method of claim 15, wherein the driving coil controller comprises: a conversion block with a force input; and a pilot control that calculates a force pilot control (F vs), wherein the force pilot control (F vs) acts on the force input.
A method for operating a long stator linear motor by moving at least one transport unit along at least one transport track having plural successively arranged driving coils arranged along the at least one transport track, the method comprising: controlling each of the plural successively arranged driving coils with a control system including a driving coil controller, wherein the driving coil controller sets control variables (StG) for driving coils of the plural successively arranged driving coils that interact with the at least one transport unit, and wherein said control system is configured to: superimpose the control variables (StG) with an excitation signal (AS) having a predetermined frequency band; determine actual variables (IG); determine a frequency response from control variables (StGAS) superimposed with the excitation signal (AS) and the actual variables (IG); determine control parameters (RP) from the frequency response; and control movement of the at least one transport unit along the at least one transport track based on the control parameters (RP).
A method for operating a long stator linear motor by moving at least one transport unit along at least one transport track having plural successively arranged driving coils arranged along the at least one transport track, the method comprising: controlling each of the plural successively arranged driving coils with a control system including a driving coil controller, wherein the driving coil controller sets control variables (StG) for driving coils of the plural successively arranged driving coils that interact with the at least one transport unit, and wherein said control system is configured to: superimpose the control variables (StG) with an excitation signal (AS) having a predetermined frequency band; determine actual variables (IG); determine a frequency response, via an evaluation unit, from control variables (StGAS) superimposed with the excitation signal (AS) and the actual variables (IG); output, from the evaluation unit, control parameters (RP); and control movement of the at least one transport unit along the at least one transport track based on the control parameters (RP).

Description

The present invention refers to a method for operating a long stator linear motor with a transport track along which a plurality of driving coils are sequentially arranged and with at least one transport unit, which is moved along the transport track, wherein each driving coil is controlled by a driving coil controller with corresponding control parameters, in that the driving coil controllers set control variables for the driving coils interacting with the transport unit.

In almost every modern production plant it is required to move parts or components also over long transport distances, by means of transport apparatus, between individual manipulation or production stations. To this end, various transport or conveyor devices are known. Frequently continuous conveyors are used in different embodiments. Conventional continuous conveyors are conveyor belts in various embodiments, in which a rotational movement of an electric drive is transformed in a linear movement of the conveyor belt. With this kind of conventional continuous conveyors flexibility is gravely limited, in particular an individual transport of individual transport units is not possible. In order to solve this problem and comply with requirements of modern flexible transport apparatus, the use of so called long stator linear motors (LLM) as a substitute for conventional continuous conveyors is spreading.

In a long stator linear motor a plurality of electric driving coils, which form the stator, are disposed along a transport track.

Citations (23)

GB1247257A
DE1963505A1
US6208497B1
US6101952A
EP1180733A1
US20020022903A1
US6876107B2
US20080115372A1
WO2004103792A1
US20130074724A1
US20130313072A1
WO2012107431A1
DE102011075174A1
US9051132B2
US20140097783A1
WO2013143783A1
US20150008768A1
DE102012025326A1
WO2015036302A1
US9617089B2
WO2015042409A1
US20150083018A1
US20150303841A1

Record as JSON

{
  "publication_number": "US10554102B2",
  "country": "US",
  "kind": "B2",
  "title": "Method for operating a long stator linear motor",
  "abstract": "In order to improve the adaptation of a long stator linear motor to requirements or conditions of individual transport units or of the transport track it is foreseen, that the control variables (StG) of a driving coil (7, 8) of long stator linear motor are superimposed with an excitation signal (AS) with a predetermined frequency band, wherein actual variables (IG) of the driving coil control are determined, from the control variables (StGAS) superimposed with the excitation signal (AS) and from the determined actual variables (IG) a frequency response is determined and from the frequency response the control parameters (RP) for this transport unit (Tx) are determined and the transport unit (Tx) is controlled using these determined control parameters (RP) for movement along the transport track.",
  "claims": [
    "1. A method for operating a long stator linear motor by moving at least one transport unit along at least one transport track having plural successively arranged driving coils arranged along the at least one transport track, the method comprising: controlling each of the plural successively arranged driving coils with a driving coil controller, wherein, during the controlling: the driving coil controller sets control variables (StG) for driving coils of the plural successively arranged driving coils that interact with the at least one transport unit; the control variables (StG) of at least one of the driving coils are superimposed with an excitation signal (AS) having a predetermined frequency band; actual variables (IG) are determined; a frequency response is determined from control variables (StGAS) superimposed with the excitation signal (AS) and the actual variables (IG); first control parameters (RP) of the driving coil controller are determined from the frequency response for the at least one transport unit; and movement of the at least one transport unit along the at least one transport track is controlled utilizing the first control parameters (RP).",
    "2. The method of claim 1, wherein the control parameters (RP) are varied in order to set a predetermined property of the frequency response.",
    "3. The method of claim 1, wherein the first control parameters (RP) control another different transport unit.",
    "4. The method of claim 1, further comprising determining second control parameters (RP) for the other different transport unit.",
    "5. The method of claim 4, wherein the driving coil controller utilizes the first or second control parameters (RP) for controlling movement of the at least one transport unit on different transport sections of the at least one transport track.",
    "6. The method of claim 1, further comprising determining the control parameters (RP) at predetermined intervals.",
    "7. The method of claim 1, further comprising determining the control parameters (RP) for different loading conditions of the at least one transport unit.",
    "8. The method of claim 7, further comprising: determining, from the frequency response, a mass of a load carried by the at least one transport unit (Tx); and selecting corresponding control parameters (RP) based on the mass.",
    "9. The method of claim 8, wherein the determining is repeated at predetermined intervals.",
    "10. The method of claim 1, further comprising: first determining, from the frequency response, resonance and anti-resonance frequencies (f R, f AR); and second determining, based on a phase passing frequency (f D) of frequency response, if the resonance and anti-resonance frequencies (f R, f AR) are attenuated.",
    "11. The method of claim 10, wherein the first determining is repeated at predetermined intervals.",
    "12. The method of claim 1, further comprising: utilizing a predetermined movement profile for the at least one transport unit; utilizing parameter estimation; collecting a system parameter value over time; and determining, from a variation of the system parameter value over time, a wear condition of the at least one transport unit.",
    "13. The method of claim 1, further comprising: utilizing a predetermined movement profile for the at least one transport unit; moving the at least one transport unit according to the predetermined movement profile; utilizing parameter estimation to determine at least one system parameter value of a model of the control system; collecting the at least one system parameter value over time; and determining, from a variation of the at least one system parameter value over time, a wear condition of the at least one transport track or of the at least one transport unit.",
    "14. The method of claim 13, further comprising: determining a set stator current (i A) for at least one driving coil of the plural successively arranged driving coils; utilizing the model of the control system when calculating a stator current of the at least one driving coil; and minimizing an error between the determined set stator current (i A) and the calculated stator current by varying the at least one system parameter value of the model of the control system.",
    "15. The method of claim 1, further comprising: implementing a pilot control that acts on an input of the driving coil controller.",
    "16. The method of claim 15, wherein the driving coil controller comprises: a speed controller with a speed input; and a pilot control that calculates a speed pilot control (v vs), wherein the speed pilot control (v vs) acts on the speed input.",
    "17. The method of claim 15, wherein the driving coil controller comprises: a conversion block with a force input; and a pilot control that calculates a force pilot control (F vs), wherein the force pilot control (F vs) acts on the force input.",
    "18. A method for operating a long stator linear motor by moving at least one transport unit along at least one transport track having plural successively arranged driving coils arranged along the at least one transport track, the method comprising: controlling each of the plural successively arranged driving coils with a control system including a driving coil controller, wherein the driving coil controller sets control variables (StG) for driving coils of the plural successively arranged driving coils that interact with the at least one transport unit, and wherein said control system is configured to: superimpose the control variables (StG) with an excitation signal (AS) having a predetermined frequency band; determine actual variables (IG); determine a frequency response from control variables (StGAS) superimposed with the excitation signal (AS) and the actual variables (IG); determine control parameters (RP) from the frequency response; and control movement of the at least one transport unit along the at least one transport track based on the control parameters (RP).",
    "19. A method for operating a long stator linear motor by moving at least one transport unit along at least one transport track having plural successively arranged driving coils arranged along the at least one transport track, the method comprising: controlling each of the plural successively arranged driving coils with a control system including a driving coil controller, wherein the driving coil controller sets control variables (StG) for driving coils of the plural successively arranged driving coils that interact with the at least one transport unit, and wherein said control system is configured to: superimpose the control variables (StG) with an excitation signal (AS) having a predetermined frequency band; determine actual variables (IG); determine a frequency response, via an evaluation unit, from control variables (StGAS) superimposed with the excitation signal (AS) and the actual variables (IG); output, from the evaluation unit, control parameters (RP); and control movement of the at least one transport unit along the at least one transport track based on the control parameters (RP)."
  ],
  "description_excerpt": "The present invention refers to a method for operating a long stator linear motor with a transport track along which a plurality of driving coils are sequentially arranged and with at least one transport unit, which is moved along the transport track, wherein each driving coil is controlled by a driving coil controller with corresponding control parameters, in that the driving coil controllers set control variables for the driving coils interacting with the transport unit.\n\nIn almost every modern production plant it is required to move parts or components also over long transport distances, by means of transport apparatus, between individual manipulation or production stations. To this end, various transport or conveyor devices are known. Frequently continuous conveyors are used in different embodiments. Conventional continuous conveyors are conveyor belts in various embodiments, in which a rotational movement of an electric drive is transformed in a linear movement of the conveyor belt. With this kind of conventional continuous conveyors flexibility is gravely limited, in particular an individual transport of individual transport units is not possible. In order to solve this problem and comply with requirements of modern flexible transport apparatus, the use of so called long stator linear motors (LLM) as a substitute for conventional continuous conveyors is spreading.\n\nIn a long stator linear motor a plurality of electric driving coils, which form the stator, are disposed along a transport track.",
  "cpc": [
    "H02K 11/30",
    "B60L 13/10",
    "B60L 15/005",
    "B60L 15/38",
    "B60L 2240/429",
    "B65G 54/02",
    "G05B 13/02",
    "G05B 13/021",
    "G05B 13/024",
    "H02K 41/02",
    "H02K 41/03",
    "H02K 41/031",
    "H02K 41/033",
    "H02P 25/06",
    "Y02T 10/64"
  ],
  "ipc": [
    "B60L 13/10",
    "B60L 15/00",
    "B60L 15/38",
    "B65G 54/02",
    "H02K 11/30",
    "H02K 41/02",
    "H02K 41/03"
  ],
  "assignees": [
    "B&R Industrial Automation GmbH"
  ],
  "inventors": [
    "Andreas Weber",
    "Joachim WEISSBACHER"
  ],
  "filing_date": "2017-05-30",
  "publication_date": "2020-02-04",
  "grant_date": "2020-02-04",
  "priority_date": "2016-05-31",
  "application_number": "US-201715608081-A",
  "family_id": "58772470",
  "cited_by_count": 6,
  "citations": [
    "GB1247257A",
    "DE1963505A1",
    "US6208497B1",
    "US6101952A",
    "EP1180733A1",
    "US20020022903A1",
    "US6876107B2",
    "US20080115372A1",
    "WO2004103792A1",
    "US20130074724A1",
    "US20130313072A1",
    "WO2012107431A1",
    "DE102011075174A1",
    "US9051132B2",
    "US20140097783A1",
    "WO2013143783A1",
    "US20150008768A1",
    "DE102012025326A1",
    "WO2015036302A1",
    "US9617089B2",
    "WO2015042409A1",
    "US20150083018A1",
    "US20150303841A1"
  ]
}

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