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Piezoelectric Torque Ripple Sensor

Detailed Technology Description

None

Supplementary Information

Patent Number: US7117754B2
Application Number: US2002281883A
Inventor: Neely, Jason | Pekarek, Steven D. | Banaskavich, Jason M. | Stutts, Daniel S.
Priority Date: 28 Oct 2002
Priority Number: US7117754B2
Application Date: 28 Oct 2002
Publication Date: 10 Oct 2006
IPC Current: G01L000302 | G01L000310 | G01L000312 | G01L000314 | H02P000610
US Class: 73862333
Assignee Applicant: The Curators of the University of Missourilumbia
Title: Torque ripple sensor and mitigation mechanism
Usefulness: Torque ripple sensor and mitigation mechanism
Summary: For sensing fluctuations in torque from a permanent magnet machine contained in housing for motor.
Novelty: Torque ripple sensor for sensing fluctuations in torque from a permanent magnet machine contained in housing for motor, comprises piezoelectric sensor coupled to permanent magnet machine

Industry

Automotive

Sub Category

Engine/Motor

Others

*Abstract

Abstract of US Patent 7,117,754 - Torque Ripple Sensor and Mitigation Mechanism: A torque ripple sensor and method for torque ripple sensing and/or mitigation. A piezoelectric sensor is positioned relative to a motor so that torque fluctuations due to torque ripple of the motor are transmitted to the sensor, resulting in strain of a piezoelectric element. A resulting signal can be amplified and conditioned for determining a magnitude of the torque ripple and/or fed into a feedback loop for applying current control or a counter-torque to the motor for torque ripple mitigation.Non-confidential Abstract of Invention: Piezoelectric torque ripple sensor (PTRS) uses elements of polyvinylidene fluoride (PVDF) or lead zirconate titanate (PZT), to sense reaction forces due to torque ripple in electric motors and generators. The PTRS senses torque tipple with very high fidelity enabling the signal to be processed and utilized in a feedback control scheme to minimize torque ripple which is undesirable due to the vibration, noise, and variation in drive torque that it causes.Marketing: Torque ripple is found in most large electric motors and generators. Torque ripple is a harmonic variation in motor output torque due to back electromotive force (EMF) interaction with stator current harmonics. Torque ripple contributes to vibration, noise, and variation in the drive torque of machines. Mitigation of torque ripple has been focused on controlling stator current harmonics based upon estimates of torque ripple. These models have not always accurately predicted the amplitude of the actual torque ripple, which varies with load and drive voltages.Recently researchers at the University of Missouri have developed a piezoelectric sensor to measure torque ripple. The sensors use elements of polyvinylidene fluoride (PVDF) or lead zirconate titanate (PZT) to sense the reaction forces. The piezoelectric torque ripple sensor picks up the torque ripple with very high fidelity enabling the signal to be utilized in a feedback control system to minimize torque ripple.

*Principal Investigator

Name: Jason Neely

Department:

Name: Steven Pekarek

Department:

Name: Jason Banaskavich

Department:

Name: Daniel Stutts

Department:

Country/Region

USA