EP0456344A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Traction motor controller for forklift vehicles
Assignee: Raymond Corp
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Filing: 1991-03-14
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Granted: —
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Expires: 2011-03-14
Abstract
Abstract A system for controlling separately excited shunt-wound dc motors, where control is achieved through microprocessor-based independent PWM control of a chopper (armature) and an H-bridge (field). Connected to the armature is an armature voltage amplifier for varying the applied armature voltage (94). A field voltage amplifier is also provided for determining the direction of motor rotation and varying the voltage (92) applied to the field winding. A first sensor is connected to the motor armature in order to determine the motor rotational speed. A second sensor is connected to the armature circuit in order to determine the armature current. A third sensor is connected to the field circuit in order to determine the field current. A decoupling controller uses the motor speed (98) and armature current (96) information, and adjusts the armature voltage (94) and the field voltage(92).
Inventors
- 👤 Isaac Avitan
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-27 08:24
CPC Classifications
H; H02; H02P; H02P7/00; H02P7/06; H02P7/18; H02P7/24; H02P7/28; H02P7/298; H02P7/2985; B; B60; B60L; B60L50/00; B60L50/50; B60L50/52; Y; Y02; Y02T; Y02T10/00; Y02T10/60; Y02T10/64; Y02T10/70
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
107 words
Apparatus for decoupling control of a dc motor having separately excited armature and field windings, comprising: a) a motor having an armature, an armature winding and a field winding, said windings being independently controlled; b) armature voltage amplifying means operatively connected to the armature of said motor for varying voltage applied thereto; c) armature current sensing means operatively connected to said armature voltage amplifying means for sensing armature current; d) field voltage amplifying means operatively connected to the field winding of said motor for varying voltage applied thereto; and e) motor speed sensing means for generating a signal representative of the rotation speed of said motor armature.
Claim 2
Dependent Claim
22 words
The decoupling control apparatus of claim 1 further comprising: f) means for providing a first reference signal proportional to desired motor speed.
Claim 3
Dependent Claim
22 words
The decoupling control apparatus of claim 2 further comprising: g) means for providing a second reference signal proportional to desired armature current.
Claim 4
Dependent Claim
46 words
The decoupling control apparatus of claim 3 further comprising: h) decoupling controlling means for receiving said first and second reference signals, said decoupling controlling means being operatively connected to said armature voltage amplifying means and to said field voltage amplifying means for controlling respective operation thereof.
Claim 5
Dependent Claim
19 words
The decoupling control apparatus of claim 4 wherein said decoupling controlling means comprises filter means and feedback controlling means.
Claim 6
Dependent Claim
46 words
The decoupling control apparatus of claim 5 wherein said decoupling controlling means further comprises summing means operatively connected to said filter means and to said feedback controlling means for providing a control signal to said armature voltage amplifying means and to said field voltage amplifying means.
Claim 7
Dependent Claim
24 words
The decoupling control apparatus of claim 1 further comprising: f) a power semiconductor operatively connected to said motor armature for providing voltage regulation thereof.
Claim 8
Dependent Claim
27 words
The decoupling control apparatus of claim 7 further comprising: g) two pairs of semiconductors operatively connected to said field winding for providing voltage regulation and motor direction.
Claim 9
Dependent Claim
23 words
The decoupling control apparatus of claim 1 further comprising: f) feedback sensing means operatively connected to said motor for sensing rotational speed thereof.
Claim 10
Dependent Claim
15 words
The decoupling control apparatus of claim 9 wherein said feedback sensing means comprises an encoder.
Claim 11
Dependent Claim
22 words
The decoupling control apparatus of claim 5 wherein said armature current sensing means generates a signal applied to said feedback controlling means.
Claim 12
Dependent Claim
19 words
The decoupling control apparatus of claim 4 wherein said motor controller means operates in accordance with computer software instructions.
Claim 13
Independent Claim
90 words
A method for controlling a dc motor having separately excited armature and field windings, the steps comprising: a) reading signals representative of desired motor speed and armature current; b) reading signals representative of actual motor speed and armature current; c) providing a filter for generating a filtered input reference; d) providing a feedback controller for generating a conditioned motor output; e) computing a filtered input reference; f) computing a conditioned motor output; and g) computing control effort as a function of said filtered input reference and said conditioned motor output.
Claim 14
Dependent Claim
25 words
The method for controlling a dc motor of claim 13, the steps further comprising repeating steps (a) - (g) to update said computed control effort.
References Cited (Backward Citations)
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