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  1. In this paper, a sliding mode current controller (SMC) is proposed for mutually coupled switched reluctance machines (MCSRMs) using a three-phase voltage source converter (VSC). A generalized state-space model of MCSRMs is first presented using a three-phase voltage source converter. Asymmetric bridge converters and three-phase voltage source converter are compared in terms of switching frequency. A sliding mode current controller is then designed to achieve constant switching frequency and lower sampling rate using a three-phase VSC. The stability analysis of the sliding controller is given to ensure the stability of the controller. Finally, the effectiveness of SMC is verified through simulation studies with a three-phase, sinusoidal excitation 12/8 MCSRM over a wide speed range. Compared to the hysteresis current control, SMC demonstrates a comparable performance in terms of torque ripples, torque root-mean-square tracking errors (RMSE) and current RMSE while achieving a constant switching frequency and much lower sampling rate. 
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  2. Reactivity controlled compression ignition (RCCI) is a promising low temperature combustion (LTC) regime that offers lower nitrogen oxides (NOx), soot and particulate matter (PM) emissions along with higher combustion efficiency compared to conventional diesel engines. It is critical to control maximum pressure rise rate (MPRR) in RCCI engines in order to safely and efficiently operate at varying engine loads. In this paper, a data-driven modeling (DDM) approach using support vector machines (SVM) is adapted to develop a linear parameter-varying (LPV) representation of MPRR for RCCI combustion. This LPV representation is then used in the design of a model predictive controller (MPC) to control crank angle of 50% of fuel mass fraction burn (CA50) and indicated mean effective pressure (IMEP) while limiting the MPRR. The results show that the LPV-MPC control strategy can track CA50 and IMEP with mean tracking errors of 0.9 CAD and 4.7 kPa, respectively, while limiting the MPRR to the maximum allowable value of 5.8 bar/CAD. 
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