System and method of speed detection in an AC induction machine
First Claim
1. A rotor speed estimation system for estimating a rotor speed of an AC induction machine, the rotor speed estimation system comprising:
- a processor programmed to;
receive an input from a data acquisition device or a plurality of sensors, the input comprising parameters of the AC induction machine during operation thereof, with the parameters comprising voltage and frequency values of power input to the AC induction machine and a load value of the AC induction machineestimate a rotor speed of the AC induction machine according to a linear speed estimation algorithm and based on name plate information (NPI) of the AC induction machine and the parameters of the AC induction machine during operation thereof;
estimate a rotor speed and a rotor bar number for the AC induction machine according to a frequency-domain signal processing algorithm;
determine if the rotor speed estimated by the frequency-domain signal processing algorithm is valid based on a comparison of the rotor bar number estimated by the frequency-domain signal processing algorithm to a pre-determined reference rotor bar number; and
if the rotor speed estimated by the frequency-domain signal processing algorithm is valid, then;
estimate a tuned rotor speed of the AC induction machine according to the linear speed estimation algorithm and based, in part, on the rotor speed estimated by the frequency-domain signal processing algorithm; and
store the tuned rotor speed on a computer readable storage medium.
2 Assignments
0 Petitions
Accused Products
Abstract
A system and method for determining rotor speed of an AC induction machine is disclosed. The system is programmed to estimate a rotor speed of the induction machine according to a linear speed estimation algorithm and based on name plate information (NPI) of the induction machine and parameters of the AC induction machine during operation thereof. The rotor speed estimation system is also programmed to estimate a rotor speed of the AC induction machine according to a frequency-domain signal processing algorithm and determine if the rotor speed estimated thereby is valid. If the rotor speed estimated by the frequency-domain signal processing algorithm is valid, then a tuned rotor speed of the AC induction machine is estimated according to the linear speed estimation algorithm and based, in part, on the rotor speed estimated by the frequency-domain signal processing algorithm.
10 Citations
20 Claims
-
1. A rotor speed estimation system for estimating a rotor speed of an AC induction machine, the rotor speed estimation system comprising:
a processor programmed to; receive an input from a data acquisition device or a plurality of sensors, the input comprising parameters of the AC induction machine during operation thereof, with the parameters comprising voltage and frequency values of power input to the AC induction machine and a load value of the AC induction machine estimate a rotor speed of the AC induction machine according to a linear speed estimation algorithm and based on name plate information (NPI) of the AC induction machine and the parameters of the AC induction machine during operation thereof; estimate a rotor speed and a rotor bar number for the AC induction machine according to a frequency-domain signal processing algorithm; determine if the rotor speed estimated by the frequency-domain signal processing algorithm is valid based on a comparison of the rotor bar number estimated by the frequency-domain signal processing algorithm to a pre-determined reference rotor bar number; and if the rotor speed estimated by the frequency-domain signal processing algorithm is valid, then; estimate a tuned rotor speed of the AC induction machine according to the linear speed estimation algorithm and based, in part, on the rotor speed estimated by the frequency-domain signal processing algorithm; and store the tuned rotor speed on a computer readable storage medium. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
10. A method of determining rotor speed of an AC induction machine, the method comprising:
causing a processor to; access name plate information (NPI) of an AC induction machine, wherein the NPI comprises a rated power, a rated speed, a rated frequency, and a rated voltage of the AC induction machine; determine each of a voltage value and a frequency value of power input to the AC induction machine during operation thereof; determine a load percentage from the AC induction machine during operation thereof; estimating estimate a rotor speed of the AC induction machine in operation based on the NPI, the voltage and frequency values of the AC induction machine, and the load percentage of the AC induction machine; estimate a rotor slot speed and associated rotor bar number for the AC induction machine according to a frequency-domain signal processing algorithm; compare the rotor bar number associated with the rotor slot speed to a reference rotor bar number, Restimate, to validate the rotor slot speed; and if the rotor slot is validated, then; calculate a revised rated speed of the AC induction machine based on the estimated rotor slot speed; estimate a tuned rotor speed of the AC induction machine based on the NPI, the voltage and frequency values of the AC induction machine, and the load percentage of the AC induction machine, with the revised rated speed replacing the rated speed from the NPI for estimation of the tuned rotor speed; and store the tuned rotor speed on a computer readable storage medium. - View Dependent Claims (11, 12, 13, 14, 15)
-
16. A non-transitory computer readable storage medium having stored thereon a computer program comprising instructions which, when executed by at least one processor, cause the at least one processor to:
-
acquire a first estimate of a motor speed of an AC motor according to a linear speed estimation algorithm and based on name plate information (NPI) of the AC motor and parameters of the AC motor during operation thereof; acquire a second estimate of the motor speed of the AC motor according to a frequency-domain based speed estimation algorithm; associate a rotor bar number of the AC motor with the second estimate of the motor speed of the AC motor according to the frequency-domain based speed estimation algorithm; perform a validation process on the second estimate of the motor speed of the AC motor based on a comparison of the rotor bar number determined from the frequency-domain based speed estimation algorithm to a previously determined reference rotor bar number, Restimate; and if the rotor speed estimated by the frequency-domain based speed estimation algorithm is valid, then; calculate a revised rated speed value for the AC motor based on the validated second estimate of the motor speed of the AC motor; input the revised rated speed value into the linear speed estimation algorithm to acquire a tuned estimate of the motor speed of the AC motor; and store the tuned motor speed on the computer readable storage medium. - View Dependent Claims (17, 18, 19, 20)
-
Specification