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Abstract.Electric vehicles (EV) are emerging as a viable and environment-friendly solution for the daily commute. However, for a broader utilization of the EV, their autonomy range has to be increased. A well dispersed charging network and a fast and efficient battery charger system becomes one important factor for the success of the EV. This paper addresses the challenges of developing such High Power chargers and proposes a modular, easily scalable and efficient implementation of a switch-mode DC-DC converter for performing the constant-current/ constantvoltage battery charging process.

Currently, it is becoming increasingly common to find numerous electronic devices installed in office and residential spaces as part of building automation solutions. These devices provide a rich set of data related to the inside and outside environment, such as indoor and outdoor temperature, humidity, and solar radiation. However, commercial of-the-shelf climatic control systems continue to rely on simple controllers like proportional-integral-derivative or even on-off, which do not take into account such variables. This work evaluates the potential performance gains of adopting more advanced controllers, in this case based on pole-placement, enhanced with additional variables, namely solar radiation and external temperature, obtained with dedicated low-cost sensors. This approach is evaluated both in simulated and real-world environments. The obtained results show that pole-placement controllers clearly outperform on-off controllers and that the use of the additional variables in pole-placement controllers allows relevant performance gains in key parameters such as error signal MSE (17%) and control signal variance (40%), when compared with simple PP controllers. The observed energy consumption savings obtained by using the additional variables are marginal (≈1%, but the reduction of the error signal MSE and control signal variance have a significant impact on energy consumption peaks and on equipment lifetime, thus largely compensating the increase in the system complexity.

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The capability of dealing with unpredictable variations of a process under manipulation is one of the most sought features when implementing digital control loops. Self tuning regulators are one type of control systems with such capability, existing several successful application of it in industry. However implementations of such systems are typically based on computationally intensive algorithms that, when applied to processes with fast dynamics, require high performance but complex and expensive embedded systems to cope with the required control-loop turnaround times. With the performance improvements brought by the new ARM Cortex M4, general purpose microcontrollers and advanced digital signal processing are no longer disjoint domains, becoming now possible to develop more versatile and robust control algorithms on affordable embedded systems with less restrictive computational limitations. Taking advantage of this architecture, this paper will present a real-time embedded adaptive controller applied to a Buck DC-DC converter. To assess the capabilities of this new architecture, comparative measurements of the algorithm's CPU usage under different system configurations and results relative to the setpoint tracking capability of the adaptive controller under time-varying dynamics will be presented.