ABSTRACT. Power electronics are the lifeblood of many exciting emerging technologies in transportation, energy systems, manufacturing, healthcare, information technology, and more. These applications demand power electronics with ever-increasing efficiency and performance with ever-decreasing size and cost. While major advances along these dimensions have been enabled by wide-bandgap semiconductor devices and digital control, further advancement is now majorly bottlenecked by passive components, particularly magnetics (i.e., inductors and transformers). Magnetics have long been integral to power electronics, but they pose fundamental size and performance challenges at small scales that impede miniaturization.

This tutorial will introduce how we can leverage an alternative passive component technology - piezoelectric components – to unlock a new era of scalability for power electronics. Piezoelectrics offer numerous potential size, performance, and manufacturability advantages, but realizing these requires fundamental re-evaluation of both power electronic circuits and piezoelectric components themselves. Accordingly, this tutorial is intended to equip power electronics researchers and engineers with the basic understanding of piezoelectric components needed to leverage them in future power converter designs. Key concepts on piezoelectric materials, components, packaging, and how they may be utilized in power electronics will be covered.

ABSTRACT. Accurate modeling and analysis are essential for understanding and designing AC-DC power converters, but their small-signal frequency response analysis can be challenging to understand and measure. This tutorial provides a structured approach to modeling and analyzing AC-DC converters, emphasizing practical simulation examples.

The first part of the tutorial will introduce the fundamentals of small-signal modeling for switch-mode power converters, starting with DC-DC converters before expanding to AC-DC systems. We will discuss the key frequency response measurements for power converters and the added complexities that arise when moving from DC-DC to AC-DC analysis. The second part of the tutorial will focus on the detailed modeling and control analysis of power factor correction (PFC) boost converters. Based on the mathematical framework and findings from recent research, we demonstrate that for control loop and output impedance analysis, a DC source set to the AC source’s RMS value can be used to accurately find the frequency response, significantly reducing simulation time. We will demonstrate how to implement this method using SIMPLIS and discuss the simulation speed advantages it provides compared to traditional AC sweep methods. By the end of this tutorial, attendees should have a solid foundation in modeling AC-DC converters and gain practical insights into using simulation tools more efficiently.

ABSTRACT. Polyphase wireless power transfer (WPT) systems can achieve much higher surface power densities (kW/m2) and specific power levels (kW/kg) compared to the conventional circular single phase WPT systems. Therefore, polyphase WPT systems can reduce the size, weight, volume, and cost of the WPT systems and can simplify the vehicle integration with less demand for space. This study presents the high-performance and compact 100-kW WPT development using polyphase electromagnetic coupling coils with rotating magnetic fields.

ABSTRACT. The enhancement-mode gallium nitride (GaN) high-electron-mobility transistor (HEMT) offers faster switching speed but introduces large dv/dt, which causes crosstalk issues and further raises the risk of false turn-on. Traditional gate drivers address this by increasing the gate resistance to reduce switching speed, but this approach also elevates switching loss, especially at high temperature because GaN HEMT’s transconductance decreases with increase of temperature. To mitigate this issue, this paper proposes a driver circuit featuring adaptive gate resistance under different temperatures. By incorporating a negative temperature coefficient (NTC) resistor, the gate resistance decreases as temperature rises. As a result, GaN devices can switch faster at high temperature, thereby reducing switching losses. Compared with the traditional driver circuit, the proposed method improves the switching speed by 31% through the adaptive gate resistance and maintains the same maximum crosstalk voltage peak under a wide temperature range.

ABSTRACT. In this digest, a multifunctional converter leg is integrated into the charger’s power circuit to enhance EV charging station resilience under power electronics converter device faults and grid outages. In the event of a device fault, it substitutes the failed converter leg, maintaining operation. During a grid outage, it assists the system as a fourth leg to the front-end converter, enabling grid-forming capability to supply power to the charging station critical loads while allowing limited power vehicle charging. This digest presents the proposed approach’s effectiveness under front-end power converter device faults, while results for grid outage scenarios will be included in the full paper.