Patent US3017294A successfully refreshed from Google Patents.
Patent US3790871A successfully refreshed from Google Patents.
US3790871A
Expired / Lapsed
US
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Individual axle wheel slip control system
Assignee: General Electric Co
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Filing: 1973-01-02
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Granted: 1974-02-05
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Expires: 1993-01-02
Abstract
Abstract An individual axle wheel slip control system for electric traction motor drives employing series type direct current traction motors is described. With this system an auxiliary source of direct current is connected to the series field winding of each individual traction motor in parallel with and in addition to the normal direct current excitation with the polarity of the auxiliary source of direct current being such that when added to the normal excitation direct current, results in a reduction of the armature current and consequently a reduction in the tractive effort of the traction motor. A field current sensor responsive only to the field current of the traction motor being controlled, is provided along with a phase control circuit which is responsive to the output of the field current sensor and to a reference signal source for establising a reference median value of field current. The phase control circuit in turn is coupled to and controls the output of the auxiliary source of direct current for increasing the auxiliary field current in response to the field current sensor detecting a sudden decrease in the field current of the traction motor below the reference median value such as which would be produced upon the occurrence of slippage. A rate of change responsive network is coupled to the field current sensor for detecting relatively rapid rates of change in the sensed field current such as would occur with a rapidly accelerating wheel slip. The rate of change network is coupled to and additionally controls the phase control circuit for further increasing the auxiliary field current supplied to the field winding of the traction motor upon the occurrence of rapidly accelerating wheel slip. A sensitivity modifying circuit is provided for decreasing the sensitivity of the rate of change network for increasing values of field current whereby for relatively low values of field current, relatively fast and large auxiliary field current corrections are provided, and for relatively large values of field current, the auxiliary field current correction is slower and of lower value. The wheel slip control system further includes an overload protection circuit that is coupled to and controls the wheel slip control circuit and that is responsive to a current transformer that senses the overall value of the auxiliary field current supplied to the traction motor. By this arrangement the level of auxiliary field current being supplied from the auxiliary direct current source is regulated to some predetermined maximum level upon the current transformer sensing an overcurrent condition.
Inventors
- 👤 R Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 13:23
CPC Classifications
B; B60; B60L; B60L3/00; B60L3/10; B60L2200/00; B60L2200/26; Y; Y02; Y02T; Y02T10/00; Y02T10/60; Y02T10/64
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
220 words
A wheel slip control system for electric traction motor drives employing series type direct current traction motors having the field and armature windings connected in series electrical circuit relationship, the improvement comprising an auxiliary source of direct current connectable to the series field winding of the series type traction motor in parallel with and in addition to the normal direct current excitation supply for the traction motor, the polarity of the auxiliary source of direct current being such that when added to the normal excitation direct current results in a reduction of the armature current with a consequent reduction in the tractive effort of the traction motor, field current sensing means responsive only to the field current of the traction motor being controlled, a reference signal source for establishing a reference median value of field current, and wheel slip control means responsive to said field current sensing means and to said reference signal source, said wheel slip control means being coupled to control the output of the auxiliary source of direct current to the field winding of the series type traction motor for increasing the supply of auxiliary field current in response to said field current sensing means sensing a sudden decrease in the field current of the traction motor below the reference median value upon the occurrence of slippage.
Claim 2
Dependent Claim
220 words
A wheel slip control system for electric traction motor drives employing series type direct current traction motors having the field and armature windings connected in series electrical circuit relationship, the improvement comprising an auxiliary source of direct current connectable to the series field winding of the series type traction motor in parallel with and in addition to the normal direct current excitation supply for the traction motor, the polarity of the auxiliary source of direct current being such that when added to the normal excitation direct current results in a reduction of the armature current with a consequent reduction in the tractive effort of the traction motor, field current sensing means responsive only to the field current of the traction motor being controlled, a reference signal source for establishing a reference median value of field current, and wheel slip control means responsive to said field current sensing means and to said reference signal source, said wheel slip control means being coupled to control the output of the auxiliary source of direct current to the field winding of the series type traction motor for increasing the supply of auxiliary field current in response to said field current sensing means sensing a sudden decrease in the field current of the traction motor below the reference median value upon the occurrence of slippage.
Claim 3
Dependent Claim
96 words
A wheel slip control system according to claim 1, further including rate of change responsive network means coupled to said field current sensing means for detecting relatively rapid rates of change in the value of sensed field current such as would occur with a rapidly accelerating wheel slip, said rate of change network means being coupled to and additionally controlling said wheel slip control means for further increasing the auxiliary field current supplied to the field winding of the traction motor by said auxiliary source of direct current upon the occurrence of rapidly accelerating wheel slip.
Claim 4
Dependent Claim
120 words
A wheel slip control system according to claim 1, wherein the auxiliary direct current source comprises rectifying means connected to the series connected field winding of the series type traction motor in parallel circuit relationship therewith and alterNating current supply network means, connected to the rectifying means, and the wheel slip control means comprises phase control circuit means included in said alternating current supply network means for supplying said rectifying means with phase controlled alternating current, and phase control gating circuit means responsive to the field current sensing means and the reference signal source for controlling the operation of the phase control circuit means to thereby control the auxiliary field current supplied to the field winding of the traction motor.
Claim 5
Dependent Claim
116 words
A wheel slip control system according to claim 1, wherein there are a multiplicity of series type direct current traction motors included in a direct current motor drive system with each traction motor having its own individual wheel slip control system, and wherein there is a common reference signal source which may be varied over a predetermined range of values representative of the desired value of field current for all series type direct current traction motors in the motor drive system to thereby establish a common median value of field current with respect to which the wheel slip control means of each individual traction motor regulates the supply of auxiliary field current to its respective motor.
Claim 6
Dependent Claim
209 words
A wheel slip control system according to claim 1, further including rate of change responsive network means coupled to said field current sensing means for detecting relatively rapid rates of change in the value of the sensed field current such as would occur with a rapidly accelerating wheel slip, said rate of change network means being coupled to and additionally controlling said wheel slip control means for further increasing the auxiliary field current supplied to the field winding of the traction motor by said auxiliary source of direct current upon the occurrence of rapidly accelerating wheel slip, and wherein the auxiliary direct current source comprises rectifying means connected to the series connected field winding of the series type traction motor in parallel circuit relationship therewith and alternating current supply network means, connected to the rectifying means, and the wheel slip control means comprises phase control circuit means included in said alternating current supply network means for supplying said rectifying means with phase controlled alternating current, and phase control gating circuit means responsive to the field current sensing means and the reference signal source for controlling the operation of the phase control circuit means to thereby control the auxiliary field current supplied to the field winding of the traction motor.
Claim 7
Dependent Claim
137 words
A wheel slip control system according to claim 5, wherein the phase control gating circuit means includes silicon control rectifiers connected in the alternating current supply network means and the phase control gating circuit means comprises magnetic amplifier gating pulse generator means having at least one turn-on gate pulse generator winding and one turn-off gate pulse generator winding with the turn-on gate pulse generator winding being coupled to and controlled by the reference signal source and the field current sensing means, as well as the rate of change responsive network means, the magnetic amplifier gating pulse generator means being so arranged that the silicon control rectifiers are maintained off during normal motoring conditions but are rendered conductive in response to the occurrence of wheel slip to thereby supply auxiliary field field current to the series field winding.
Claim 8
Dependent Claim
66 words
A wheel slip control system according to claim 6, further including sensitivity modifying means for decreasing the sensitivity of the rate of change responsive network means in response to increasing values of field current whereby for relatively low values of field current relatively fast and large auxiliary field current corrections are provided and for relatively large values of field current the correction is slower and less.
Claim 9
Dependent Claim
83 words
A wheel slip control System according to claim 7, further including overload protection circuit means coupled to the turn-off gate pulse generator winding of the magnetic amplifier gate pulse generator means, and current transformer means for sensing the magnitude of the alternating current supplied to the rectifying means, said overload protection circuit means serving to reduce the level of alternating current being supplied from the auxiliary direct current source to some predetermined maximum level upon the current transformer means sensing an overcurrent condition.
Claim 10
Dependent Claim
69 words
A wheel slip control system according to claim 8, further including pretest and energizing relay network means connected to the wheel slip control system and responsive to the motoring control of the traction motor for subjecting the wheel slip control system to a malfunction test in advance of the traction motor being energized and thereafter allowing the motor to operate in a normal manner upon no malfunction being detected.
Claim 11
Dependent Claim
97 words
A wheel slip control system according to claim 9, wherein there are a multiplicity of series type direct current traction motors included in a direct current motor drive system with each traction motor having its own individual wheel slip control system, and wherein there is a common reference signal source for all series type direct current traction motors in the motor drive system for establishing a common median value of field current with respect to which the wheel slip control means of each individual traction motor regulates the supply of auxiliary field current to its respective motor.
Claim 12
Dependent Claim
364 words
A wheel slip control system for electric traction motor drives employing series type direct current traction motors having the field and armature windings connected in series electrical circuit relationship, the improvement comprising an auxiliary source of direct current connectable to the series field winding of the series type traction motor in parallel with and in addition to the normal direct current excitation supply for the traction motor, the polarity of the auxiliary source of direct current being such that when added to the normal excitation direct current results in a reduction of the armature current with a consequent reduction in the tractive effort of the traction motor, field current sensing means responsive only to the field current of the traction motor being controlled, a reference signal source for establishing a reference median value of field current, and wheel slip control means responsive to said field current sensing means and to said reference signal source, said wheel slip control means being coupled to control the output of the auxiliary source of direct current to the field winding of the series type traction motor for increasing the supply of auxiliary field current in response to said field current sensing means sensing a sudden decrease in the field current of the traction motor below the reference median value upon the occurrence of slippage, rate of change responsive network means coupled to said field current sensing means for detecting relatively rapid rates of change in the value of the sensed field current such as would occur with a rapidly accelerating wheel slip, said rate of change network means being coupled to and additionally controlling said wheel slip control means for further increasing the auxiliary field current supplied to the field winding of the traction motor by said auxiliary source of direct current upon the occurrence of rapidly accelerating wheel slip, and sensitivity modifying means for decreasing the sensitivity of the rate of change responsive network means in response to increasing values of field current whereby for relatively low values of field current relatively fast and large field current corrections are provided and for relatively high values of field current the rate of change correction is slower and less.
Claim 13
Dependent Claim
364 words
A wheel slip control system for electric traction motor drives employing series type direct current traction motors having the field and armature windings connected in series electrical circuit relationship, the improvement comprising an auxiliary source of direct current connectable to the series field winding of the series type traction motor in parallel with and in addition to the normal direct current excitation supply for the traction motor, the polarity of the auxiliary source of direct current being such that when added to the normal excitation direct current results in a reduction of the armature current with a consequent reduction in the tractive effort of the traction motor, field current sensing means responsive only to the field current of the traction motor being controlled, a reference signal source for establishing a reference median value of field current, and wheel slip control means responsive to said field current sensing means and to said reference signal source, said wheel slip control means being coupled to control the output of the auxiliary source of direct current to the field winding of the series type traction motor for increasing the supply of auxiliary field current in response to said field current sensing means sensing a sudden decrease in the field current of the traction motor below the reference median value upon the occurrence of slippage, rate of change responsive network means coupled to said field current sensing means for detecting relatively rapid rates of change in the value of the sensed field current such as would occur with a rapidly accelerating wheel slip, said rate of change network means being coupled to and additionally controlling said wheel slip control means for further increasing the auxiliary field current supplied to the field winding of the traction motor by said auxiliary source of direct current upon the occurrence of rapidly accelerating wheel slip, and sensitivity modifying means for decreasing the sensitivity of the rate of change responsive network means in response to increasing values of field current whereby for relatively low values of field current relatively fast and large field current corrections are provided and for relatively high values of field current the rate of change correction is slower and less.
Claim 14
Dependent Claim
296 words
A wheel slip control system for electric traction motor drives employing series type direct current traction motors haviNg the field and armature windings connected in series electrical circuit relationship, the improvement comprising an auxiliary source of direct current connectable to the series field winding of the series type traction motor in parallel with and in addition to the normal direct current excitation supply for the traction motor, the polarity of the auxiliary source of direct current being such that when added to the normal excitation direct current results in a reduction of the armature current with a consequent reduction in the tractive effort of the traction motor, field current sensing means responsive only to the field current of the traction motor being controlled, a reference signal source for establishing a reference median value of field current, and wheel slip control means responsive to said field current sensing means and to said reference signal source, said wheel slip control means being coupled to control the output of the auxiliary source of direct current to the field winding of the series type traction motor for increasing the supply of auxiliary field current in response to said field current sensing means sensing a sudden decrease in the field current of the traction motor below the reference median value upon the occurrence of slippage, overload protection circuit means coupled to and additionally controlling said wheel slip control means, and current transformer means for sensing the magnitude of the auxiliary field current applied to the traction motor, said current transformer means being coupled to and controlling said overload protection circuit means for reducing the level of auxiliary field current being supplied from the auxiliary direct current source to some predetermined maximum level upon the current transformer means sensing an overcurrent condition.
Claim 15
Dependent Claim
296 words
A wheel slip control system for electric traction motor drives employing series type direct current traction motors haviNg the field and armature windings connected in series electrical circuit relationship, the improvement comprising an auxiliary source of direct current connectable to the series field winding of the series type traction motor in parallel with and in addition to the normal direct current excitation supply for the traction motor, the polarity of the auxiliary source of direct current being such that when added to the normal excitation direct current results in a reduction of the armature current with a consequent reduction in the tractive effort of the traction motor, field current sensing means responsive only to the field current of the traction motor being controlled, a reference signal source for establishing a reference median value of field current, and wheel slip control means responsive to said field current sensing means and to said reference signal source, said wheel slip control means being coupled to control the output of the auxiliary source of direct current to the field winding of the series type traction motor for increasing the supply of auxiliary field current in response to said field current sensing means sensing a sudden decrease in the field current of the traction motor below the reference median value upon the occurrence of slippage, overload protection circuit means coupled to and additionally controlling said wheel slip control means, and current transformer means for sensing the magnitude of the auxiliary field current applied to the traction motor, said current transformer means being coupled to and controlling said overload protection circuit means for reducing the level of auxiliary field current being supplied from the auxiliary direct current source to some predetermined maximum level upon the current transformer means sensing an overcurrent condition.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-02-04 | 1977-08-06 | 1978-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-04 | 1981-08-06 | 1982-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-04 | 1985-08-06 | 1986-02-05 | $7700.00 | Window Closed / Lapsed |