Supercapacitor assisted low dropout regulators (SCALDO) with reduced switches: A new approach to high efficiency VRM designs

Supercapacitor assisted low dropout (SCALDO) regulator is a new approach to develop high efficiency DC-DC converters with supercapacitors used for energy recovery. One limitation in these topologies is that in some configurations a large number of low-speed switches are required. If the SCALDO technique is adapted to build voltage regulator modules (VRM), it is necessary to reduce number of switches combined with a high current capable LDO. A new topology-variation with less number of switches can be achieved by reconfiguring the original SCALDO and adding an extra LDO to the circuit. The paper presents a summary of some preliminary work, and experimental results for a 2.5V proof of concept-prototype

Communication‐less Synchronous Rectification for In Motion Wireless Charging

This thesis puts forward a control scheme to allow for synchronous rectification for dynamic wireless power transfer. The automotive industry is transitioning away from internal combustion engines (ICEs) and towards electric vehicles (EVs). This transition is spurred by the environmental and economic benefits EVs offer over ICEs. However, further improvements can still be made to how electric vehicles operate. One of these improvements is the technology of in motion wireless charging or dynamic wireless power transfer. In motion wireless charging offers the ability to remove existing range anxiety concerns for EVs. It also offers the potential for a reduction in battery sizes for EVs, which are the primary cost of EVs, this in turn decreases the total costs of mass EV adoption. Traditional implementations of in motion wireless charging utilize passive rectification to simplify controls between embedded primary pads and the vehicle. However, this solution while effective, limits the potential benefits of wireless charging. The use of synchronous or active rectification techniques, offer improved performance, control techniques, and bidirectional capabilities. However, the reason synchronous rectification is not already used in in motion charging is the complexity of synchronization over wireless communication. To move past this challenge, this thesis investigates a synchronization scheme that can be achieved without communication by taking advantage of induced free resonant currents in the vehicle’s tuning network to synchronize the switching transitions to receive power. In this thesis a traditional in motion wireless charging system utilizing passive rectification is designed and built as a benchmark for dynamic charging. Simulations of this control scheme are presented. Practical considerations are addressed for hardware realization. Finally, the control approach is validated through hardware in static and dynamic applications