Mcmaster University

Fca US LLC

Enedym Inc.

Jin Ye

Ali Emadi

Hong Yang

Pawel Malysz

Ran Gu

Jian Lin

More accurate and robust battery state estimation (BSE) techniques for a battery system of an electrified vehicle include estimating a current bias or offset generated by a current sensor and then adjusting the measured current to compensate for the estimated current bias. The techniques obtain nominal parameters for a battery model of the battery system based on a measured temperature and an estimated open circuit voltage (OCV). The techniques use these nominal parameters and the corrected measured current to estimate the OCV, a capacity, and an impedance of the battery system. The techniques utilize the OCV to estimate a state of charge (SOC) of the battery system. The techniques also estimate a state of health (SOH) of the battery system based on its estimated capacity and impedance. The techniques then control the electrified vehicle based on the SOC and/or the SOH.

Techniques for robust battery state estimation

A method for controlling a switched reluctance motor, the method comprising: receiving a reference torque T; receiving an indication of a present rotor position &#x3b8; for the switched reluctance motor; determining at least one of: a reference current ifor a (k&#x2212;1)phase, a reference current ifor a (k)phase, and a reference current ifor a (k+1)phase; and outputting the determined at least one reference current to a current controller operatively coupled to the switched reluctance motor, wherein the determined at least one reference current is based on an objective function comprising the squares of phase current and derivatives of current reference.

Torque ripple reduction in switched reluctance motor drives

Various embodiments are described herein for a system and method to eliminate mutual flux effect on rotor position estimation of switched reluctance motor (SRM) drives at rotating shaft conditions without a prior knowledge of mutual flux. Neglecting the magnetic saturation, the operation of conventional self-inductance estimation using phase current slope difference method can be classified into three modes: Mode I, II and III. At positive-current-slope and negative-current-slope sampling point of one phase, the sign of current slope of the other phase changes in Mode I and II, but does not change in Mode III. In one example embodiment, in order to operate the self-inductance estimation in Mode III, a variable-hysteresis-band current control method is proposed for the incoming phase and variable-sampling method is proposed for the outgoing phase.

Systems and methods for rotor position determination

Various embodiments are described herein for an extended-speed low-ripple torque control of a switched reluctance motor (SRM) using online torque sharing function (TSF). Two operational modes of an online TSF are defined during the commutation: In Mode I, absolute value of rate of change of flux linkage (ARCFL) of incoming phase is higher than outgoing phase; in Mode II, ARCFL of outgoing phase is higher than incoming phase. To compensate the torque error produced by imperfect tracking of phase current, a proportional and integral compensator with torque error is added to the torque reference of outgoing phase in Mode I and incoming phase in Mode II. Therefore, the total torque is determined by the phase with lower ARCFL rather than the phase with higher ARCFL as in conventional TSFs.

Extended-speed low-ripple torque control of switched reluctance motor drives

An electrified vehicle and method for estimating peak power of a battery system of the electrified vehicle are presented. In one exemplary implementation, the method includes receiving, at a controller of the electrified vehicle, measured current, voltage, and temperature of the battery system and determining, at the controller, operating parameters for the battery system based on the measured current, voltage, and temperature. An initial peak current at a start of a current prediction period for the battery system is determined, at the controller, based on the operating parameters, and an instantaneous peak current of the battery system is determined based on its initial peak current by performing voltage-limited extrapolation of resistances and open-circuit voltage (VLERO) of a battery model for the battery system. The battery system and an electric motor of the electrified vehicle are controlled, by the controller, based on the instantaneous peak current.

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Hamilton, Canada

Jin Ye