I'd be glad to assist you with understanding the losses in switched reluctance motors (SRMs) and the research article you mentioned. However, I'm unable to access the full content of the article due to restrictions. To provide the most accurate and relevant information, I'll need more context about the specific losses you're interested in and any key findings or methodologies discussed in the article.
Here are some general points to consider regarding SRM losses:
Types of Losses in SRMs:
Copper losses: Caused by the resistance of the stator and rotor windings, increasing with current squared (I^2). Minimized by using larger conductors, optimizing winding design, and reducing operating temperature.
Iron losses: Comprise hysteresis losses (due to magnetization reversal in the iron core) and eddy current losses (induced currents within the core). Minimized by using high-grade electrical steel, proper lamination thickness, and core shaping to reduce eddy current paths.
Mechanical losses: Include windage friction, bearing friction, and cogging torque (torque pulsations due to rotor position). Reduced by using low-friction bearings, optimized air gaps, and minimizing cogging through rotor pole shaping.
Switching losses: Occur during commutation (turning on/off of phases) due to high voltage and current transients. Minimized by using advanced gate drivers, optimizing switching times, and employing soft-switching techniques.
Factors Affecting Losses:
Operating speed and torque: Higher speeds and torques typically lead to higher losses due to increased current and magnetic interaction.
Temperature: Iron losses rise significantly with temperature, while copper losses increase moderately. Proper thermal management is crucial.
Design parameters: Motor geometry, material selection, and winding design all impact losses. Optimizing these factors is essential for efficiency.
Estimation Methods:
Analytical models: Based on simplifying assumptions and empirical formulas, they provide quick estimates but may not be highly accurate for complex designs.
Finite element analysis (FEA): Provides detailed simulations of electromagnetic and thermal behavior, offering more accurate loss predictions but requiring significant computational resources.
Experimental measurements: Direct measurement of motor losses using specialized equipment is the most accurate method but can be expensive and time-consuming.