Power Electronics Laboratory

The efficiency is one of the most important properties of power converters. High efficiency means:

• Small cooling system
• Reduced energy costs

We design highly efficient power converters by:

• Creating new, highly efficient topologies
• Optimizing passive components
• Optimizing the control system

Advanced control systems allow to improve the system performance. This improvement comes for free in terms of cost of production when a better software can be implemented using the same hardware. Our research work focuses on the 3 following subtopics:

• High Performance, Sensorless Control of Electric Drives

Sensorless control of electric drives is a very popular asset to increase robustness and reduce cost. We develop new high performance, sensorless control algorithms for the sensorless control of high precision motors.

Optimized PWM and pulse patterns

Smart PWM schemes or optimized pulse patterns enable improved harmonic performances and/or reduced converter losses. As for the advanced control system, it generally enables improved performance at no or only low additional production costs.

We develop efficient PWM schemes for a wide range of power converters. We have extensive experience in implementing these state-of-the-art microcontrollers for complex converters or PWM schemes, we have experience in implementing PWM schemes on FPGA.

Optimal and model predictive control for high performance

The use of optimal control techniques such as Model Predictive Control (MPC), Kalman filters and system identification generally allow to improve control performance in terms of precision, bandwidth, robustness and reduced noise impact.

We develop simple and very powerful control techniques to improve the performance of power electronic systems. We have extensive experience in implementing powerful control schemes on state-of-the-art microcontrollers.

Optimized systems

The use of optimization enables designing the power converter solution that best matches the specifications using computer power.

Our research work concentrates on

• Designing precise mathematical models of power converters and their components suitable for use in optimization algorithms
• Formulating the design of power converters as optimization problems. If the control system and component parameters are often strongly linked, we also deal with joint optimization, in which we simultaneously optimized converter and control system parameters

Passive components play a key role in the cost, efficiency, weight and volume of power converters. In order to minimize costs, weight and volume and maximize efficiency, we:

• develop accurate models of passive components and filters for use in optimization
• develop efficient design methods for magnetic components such as coils and transformers

The replacement of classical Si power semiconductors with wide band gap power semiconductors such as SiC or GaN allows:

• increasing the energy efficiency of power converters
• reducing the size of passive components and of the cooling system.

Wide band gap power semiconductors are still fairly expensive. However, they can be considered in applications where there are strict design limitations such as reduced converter size or high temperature operation.

We study the design and control of SiC and GaN in power converters to determine in which applications they can already be advantageously be applied.