Veysel T. Buyukdegirmenci

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This paper presents a comparative study of induction machines (IMs) and interior permanent-magnet synchronous machines (IPMSMs) in traction applications. Machines are chosen to have similar ratings to operate in the same vector-controlled drive system and to achieve a fair comparison. Due to the dynamic nature of traction applications, static efficiency(More)
This paper presents general design requirements and analysis of roadbed inductive power transfer systems for charging electric vehicles as they drive. Three different generic roadbed geometries, based on a long wire loop, sectioned wire loops, and spaced loops, are presented and investigated. The coupling between the track coil and the pickup coil is(More)
The conventional wisdom on peak-duty drive design leads to vastly oversized machines, following design strategies that are based on continuous ratings. This paper investigates induction machine time ratings that allow peak electrical capabilities to be fully attained. The machine transient thermal response is used to identify four heating regimes based on(More)
This paper investigates short-term torque capability maximization in electric machines based on thermal time ratings. To understand time ratings, machine transient thermal response is divided into four regimes: subtransient, transition, transient, and temperature creep. Each regime is discussed separately. For modest overload conditions, an exponential(More)
Vector-controlled induction motor drives include several design and control variables that affect power losses. Flux may be weakened to reduce machine losses; switching and conduction losses in the inverter are reduced by adjusting the flux ripple and current hysteresis bands. This paper combines the machine and inverter to investigate the effects of(More)
This paper proposes an exponential adaptive perturb and observe algorithm (EAPO) for real-time optimization of dynamic systems. Other adaptive methods are reviewed, and the mathematical formulation of the proposed EAPO is presented. Convergence and stability are discussed. Design requirements for applying EAPO are also addressed in an example for impedance(More)
This paper examines the impact of decreasing microprocessor supply voltage on system efficiency and performance. While digital designers can decrease power consumption in a microprocessor by lowering its supply voltage, efficiency and performance trade-offs arise in the power supply that offset the power reduction. Conduction losses and switching losses in(More)
This paper evaluates maximum instantaneous torque capabilities of induction machines, and analyzes field-oriented control and related control strategies that can deliver high momentary forces. The analyses show that by using the entire voltage headroom, in principle up to 300% of the breakdown torque can be obtained at stall without saturating the magnetic(More)
This paper discusses stability conditions of direct torque control (DTC) based on a singular perturbation perspective. Input-output decoupling is discussed and asymptotic-input-output-decoupling is proposed in order to improve erratic DTC performance reported by practitioners. Stability analysis shows that DTC is applicable for low-leakage machines. A(More)
Accurate knowledge of winding temperature is critical for the control, protection, and real-time monitoring of high-performance electric machines. Lumped parameter and finite element analyses can be used to model thermal stress, but both have drawbacks in applications where fast estimates of local temperature distributions are necessary. To overcome this, a(More)