Switched reluctance position sensing

Claim 3

The method as set forth in claim 1, wherein the reference flux linkage value is a first reference flux linkage value.

Claim 4

The method as set forth in claim 2, wherein the reference flux linkage value look-up table selected is based on the slope of the first reference flux linkage value to phase current value curve being greater than the slope of the second reference flux linkage value to phase current value curve.

Claim 5

The method as set forth in claim 1, wherein the reference flux linkage value is a second reference flux linkage value.

Claim 6

The method as set forth in claim 4, wherein the reference flux linkage value look-up table selected is based on the slope of the second reference flux linkage value to phase current value curve being greater than the slope of the first reference flux linkage value to phase current value curve.

Claim 7

The method as set forth in claim 1, wherein the act of determining a shaft angle further comprises the act of providing a look-up table, wherein the look-up table provides a relationship between the reference flux linkage value, the phase current, and the shaft angle.

Claim 8

The method as set forth in claim 6, wherein the act of providing a look-up table is maintained in software.

Claim 9

The method as set forth in claim 6, wherein the act of providing the look-up table further comprises the act of providing at least one set of data points defining a phase current value and flux reference linkage value to shaft angle relationship.

Claim 10

The method as set forth in claim 6, wherein the act of providing the look-up table further comprises the act of providing at least one set of data points defining a phase current value and reference flux linkage value to shaft angle relationship.

Claim 11

A rotor position sensing circuit for a switched reluctance motor, the circuit comprising: a measuring circuit to measure phase voltage and phase current; a comparator circuit to compare an estimated flux linkage value to a one of a first and second reference flux linkage value that is selected based on the slope between the phase current value and the reference flux linkage value; a reference flux linkage value look-up table that is selected based on the slope of the first reference flux linkage value to phase current curve being greater than the slope of the second reference flux linkage value to phase current value curve to determine a shaft angle, the shaft angle being based on the phase current value and the reference flux linkage value; and an estimator to determine rotor position based on the shaft angle.

Claim 12

A rotor position sensing circuit for a switched reluctance motor, the circuit comprising: a measuring circuit to measure phase voltage and phase current; a comparator circuit to compare an estimated flux linkage value to a one of a first and second reference flux linkage value that is selected based on the slope between the phase current value and the reference flux linkage value; a reference flux linkage value look-up table that is selected based on the slope of the first reference flux linkage value to phase current curve being greater than the slope of the second reference flux linkage value to phase current value curve to determine a shaft angle, the shaft angle being based on the phase current value and the reference flux linkage value; and an estimator to determine rotor position based on the shaft angle.

Claim 13

The circuit as set forth in claim 10, further comprising a sampler, wherein measurement of the phase current occurs when the estimated flux linkage value is approximately equal to the reference flux linkage value.

Claim 14

A switched reluctance motor comprising: a stator; a rotor; and a rotor position sensing circuit, wherein the rotor position sensing circuit further comprises: a measuring circuit to measure phase voltage and phase current; a comparator circuit to compare an estimated flux linkage value to a one of a first and second reference flux linkage value that is selected based on the slope between the phase current value and the reference flux linkage value; a reference flux linkage value look-up table that is selected based on the slope of the first reference flux linkage value to phase current curve being greater than the slope of the second reference flux linkage value to phase current value curve to determine a shaft angle, the shaft angle being based on the phase current value and the reference flux linkage value; and an estimator to determine rotor position based on the shaft angle.

Claim 15

A switched reluctance motor comprising: a stator; a rotor; and a rotor position sensing circuit, wherein the rotor position sensing circuit further comprises: a measuring circuit to measure phase voltage and phase current; a comparator circuit to compare an estimated flux linkage value to a one of a first and second reference flux linkage value that is selected based on the slope between the phase current value and the reference flux linkage value; a reference flux linkage value look-up table that is selected based on the slope of the first reference flux linkage value to phase current curve being greater than the slope of the second reference flux linkage value to phase current value curve to determine a shaft angle, the shaft angle being based on the phase current value and the reference flux linkage value; and an estimator to determine rotor position based on the shaft angle.

Claim 16

The circuit as set forth in claim 12, further comprising a sampler, wherein measurement of the phase current occurs when the estimated flux linkage value is approximately equal to the reference flux linkage value.

Claim 17

A rotor position sensing circuit for a switched reluctance motor, the circuit comprising: first measuring means for measuring a phase voltage; second measuring means for measuring a phase current; first calculating means for determining an estimated flux linkage value from the phase voltage and the phase current; third measuring means for measuring the phase current when the estimated flux linkage value is approximately equal to a reference flux linkage value; second calculating means for determining a shaft angle, the shaft angle being based on the reference flux linkage value and the measured phase current value; and third calculating means for determining rotor position, the rotor position being based on the shaft angle and the speed.

Claim 18

A rotor position sensing circuit for a switched reluctance motor, the circuit comprising: first measuring means for measuring a phase voltage; second measuring means for measuring a phase current; first calculating means for determining an estimated flux linkage value from the phase voltage and the phase current; third measuring means for measuring the phase current when the estimated flux linkage value is approximately equal to a reference flux linkage value; second calculating means for determining a shaft angle, the shaft angle being based on the reference flux linkage value and the measured phase current value; and third calculating means for determining rotor position, the rotor position being based on the shaft angle and the speed.

Claim 19

The circuit as set forth in claim 14, wherein the reference flux linkage value is a first flux linkage reference value.

Claim 20

The circuit as set forth in claim 14, wherein the reference flux linkage value is a second flux linkage reference value.

Claim 21

The circuit as set forth in claim 14, wherein the first calculating means further comprises a look-up table, wherein the look-up table provides a relationship between the reference flux linkage value, the phase current and the shaft angle.

Claim 22

The circuit as set forth in claim 17, wherein the look-up table is maintained in software.

Claim 23

The circuit as set forth in claim 17, wherein the look-up table further comprises at least one set of data points defining a phase current value and a flux linkage reference value to shaft angle relationship.

Claim 24

The circuit as set forth in claim 14, wherein selection of the reference flux linkage value is dependent on the slope between the phase current value and the reference flux linkage value.

Claim 25

The circuit as set forth in claim 20, wherein the reference flux linkage value look-up table selected is based on the slope of the first flux linkage reference value to phase current value curve being greater than the slope of the second flux linkage reference value to phase current value curve.

Claim 26

The circuit as set forth in claim 20, wherein the reference flux linkage value look-up table selected is based on the slope of the second flux linkage reference value to phase current value curve being greater than the slope of the first flux linkage reference value to phase current value curve.

Claim 27

A data processing system for determining rotor position of a switched reluctance motor, the processing system comprising: a computer processor for processing data; a storage medium for storing data; a trigger signal for initializing the storage medium; a measuring circuit for processing data regarding measurement of a phase voltage and measurement of a phase current; a comparator circuit for processing data regarding the phase voltage and the phase current and for determining an estimated flux linkage value; a look-up table circuit for processing data regarding a reference flux linkage value and the measured phase current value and for determining a shaft angle; and an integrator circuit for processing data regarding the shaft angle and the speed and for determining rotor position.

Claim 28

A data processing system for determining rotor position of a switched reluctance motor, the processing system comprising: a computer processor for processing data; a storage medium for storing data; a trigger signal for initializing the storage medium; a measuring circuit for processing data regarding measurement of a phase voltage and measurement of a phase current; a comparator circuit for processing data regarding the phase voltage and the phase current and for determining an estimated flux linkage value; a look-up table circuit for processing data regarding a reference flux linkage value and the measured phase current value and for determining a shaft angle; and an integrator circuit for processing data regarding the shaft angle and the speed and for determining rotor position.

Claim 29

The system as set forth in claim 23, wherein the reference linkage flux value is a first flux linkage reference value.

Claim 30

The system as set forth in claim 23, wherein the reference flux linkage value is a second flux linkage reference value.

Claim 31

The system as set forth in claim 23, wherein the look-up table circuit provides a relationship between reference flux linkage value, the phase current value and the shaft angle.

Claim 32

The system as set forth in claim 26, wherein the look-up table circuit is maintained in software.

Claim 33

The system as set forth in claim 26, wherein the look-up table circuit further comprises at least one set of data points defining a phase current value and reference flux linkage value to shaft angle relationship.

Claim 34

The system as set forth in claim 26, wherein selection of the reference flux linkage value is dependent on the slope between the phase current value and the reference flux linkage value to shaft angle relationship.

Claim 35

The system as set forth in claim 29, wherein the reference flux linkage value look-up table selected is based on the slope of the first flux linkage reference value to phase current value curve being greater than the slope of the second flux linkage value to phase current value curve.

Claim 36

The system as set forth in claim 29, wherein the estimated flux linkage value look-up table selected is based on the slope of the second flux linkage reference value to phase current value curve being greater than the slope of the first flux linkage reference value to phase current value curve.

Claim 37

A rotor position sensing circuit for a switched reluctance motor, the circuit comprising: a measuring circuit to measure phase voltage and phase current; a comparator circuit to compare an estimated flux linkage value to a one of a first and second reference flux linkage value that is selected based on the slope between the phase current value and the reference flux linkage value; a reference flux linkage value look-up table that is selected based on the slope of the second reference flux linkage value to phase current curve being greater than the slope of the first reference flux linkage value to phase current value curve to determine a shaft angle, the shaft angle being based on the phase current value and the reference flux linkage value; and an estimator to determine rotor position based on the shaft angle.

Claim 38

A rotor position sensing circuit for a switched reluctance motor, the circuit comprising: a measuring circuit to measure phase voltage and phase current; a comparator circuit to compare an estimated flux linkage value to a one of a first and second reference flux linkage value that is selected based on the slope between the phase current value and the reference flux linkage value; a reference flux linkage value look-up table that is selected based on the slope of the second reference flux linkage value to phase current curve being greater than the slope of the first reference flux linkage value to phase current value curve to determine a shaft angle, the shaft angle being based on the phase current value and the reference flux linkage value; and an estimator to determine rotor position based on the shaft angle.

Claim 39

The circuit as set forth in claim 32, further comprising a sampler, wherein measurement of the phase current occurs when the estimated flux linkage value is approximately equal to the reference flux linkage value.

Claim 40

A switched reluctance motor comprising: a stator; a rotor; and a rotor position sensing circuit, wherein the rotor position sensing circuit further comprises: a measuring circuit to measure phase voltage and phase current; a comparator circuit to compare an estimated flux linkage value to a one of a first and second reference flux linkage value that is selected based on the slope between the phase current value and the reference flux linkage value; a reference flux linkage value look-up table that is selected based on the slope of the second reference flux linkage value to phase current curve being greater than the slope of the first reference flux linkage value to phase current value curve to determine a shaft angle, the shaft angle being based on the phase current value and the reference flux linkage value; and an estimator to determine rotor position based on the shaft angle.

Claim 41

A switched reluctance motor comprising: a stator; a rotor; and a rotor position sensing circuit, wherein the rotor position sensing circuit further comprises: a measuring circuit to measure phase voltage and phase current; a comparator circuit to compare an estimated flux linkage value to a one of a first and second reference flux linkage value that is selected based on the slope between the phase current value and the reference flux linkage value; a reference flux linkage value look-up table that is selected based on the slope of the second reference flux linkage value to phase current curve being greater than the slope of the first reference flux linkage value to phase current value curve to determine a shaft angle, the shaft angle being based on the phase current value and the reference flux linkage value; and an estimator to determine rotor position based on the shaft angle.

Claim 42

The circuit as set forth in claim 34, further comprising a sampler, wherein measurement of the phase current occurs when the estimated flux linkage value is approximately equal to the reference flux linkage value.