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Contactless charging of electric vehicles by means of inductive power transfer is becoming increasingly popular in the recent years. In contrast to wired power interfaces, userfriendly and secure wireless links with no physical contact are preferable. Especially in the higher power range (>100kW), three-phase approaches are an encouraging alternative to singlephase systems due to great EMC benefits. While compensation of single-phase systems is comparatively simple, the static tuning procedure is much more complex for three-phase systems. Aggravating, system parameter drifts arising from slightly mismatched positioning and thermal influences shift the systems current working point away from the optimal one for which the whole system is tuned statically. As an essential base, in a first part this paper introduces an appropriate approach for the static tuning of a three-phase system and discusses the effects of parameter drifts on the pickup. Based on the static tuning, concept ideas for an automatic retuning of the pickup during operation are presented in the second part.

Today, in modern three-phase inverter based AC drive systems for electric and hybrid electric vehicles a trend to high voltage levels can be observed. An increase of voltage at constantly leaved power level inherently leads to lower currents in the inverter and in the motor compared with low voltage based drive systems. However, ensuring personal safety at high voltage levels is difficult, especially in accidental cases where possibly unpredictable fault conditions occur. Feeding the required electrical power at low-voltage trough two separate threephase stars to the motor is a possible approach to keep the upcoming currents small. An ideal precondition for further reduction of currents is the distribution of required power to several or all of the vehicle's wheels with an in-wheel drive concept. Along with vehicle drive-train the proposed concept is generally applicable to low-voltage based drive systems with relatively high currents. The paper discusses mathematical modelling and two possible current control approaches for the two-star IPMSM.

The use of suitable examples is a key to teach abstract, theoretical concepts. Interactive computer software allows us to use such examples to create attractive learning environments that not only appeal to students, but also enhance knowledge transfer in class. However, developing such highly specialized systems is costly, resulting in only few of these tools being developed for higher education. This article introduces InfoTraffic, a collection of new learning environments to support the introduction of fundamental concepts of computer science and mathematics in order to be of long-lived value. We describe the didactical concepts behind the interactive and concrete approach of InfoTraffic, and illustrate them through two of its learning environments -one targeted at propositional logic, the other at queueing theory.

No abstract