Power Modules for Multi-level Converters
State-of-the-art multi-level converter systems make use of power semiconductors in industrial standard-packages with isolated baseplates. For applications in the energy grid a system lifetime of 40 years and more has to be guaranteed – a real challenge against the background of power electronics existing for only about 35 years.
Compared to traditional two-level topologies, multi-level systems have special requirements regarding the power modules. On the other hand, several of these topologies provide additional degrees of freedom.
In order to optimize the complete converter system, Fraunhofer IISB is developing and qualifying new specific power modules. These power modules are required to utilize the full potential of modern power semiconductors in multi-level systems. By using specially adopted joining technologies the system lifetime is increased compared to state-of-the-art modules. New application-specific power module concepts allow the integration of protection mechanisms to improve the converter behavior and availability in case of system or device failures.
Control of Multi-level Converters
One drawback of multi-level topology concepts is the increased number of semiconductor switches to be controlled. Especially for systems with small and medium power, the control effort can represent a significant proportion of the total system cost. Fraunhofer IISB is developing optimized control and communication systems as key elements for cost-efficient multi-level systems. The work is focused on:
Power Modules for Multi-level Converters
State-of-the-art multi-level converter systems make use of power semiconductors in industrial standard-packages with isolated baseplates. For applications in the energy grid a system lifetime of 40 years and more has to be guaranteed – a real challenge against the background that power electronics at all exists for only about 35 years.
Compared to traditional two-level topologies, multi-level systems have special requirements regarding the power modules. On the other hand, several of these topologies provide additional degrees of freedom.
In order to optimize the complete converter system Fraunhofer IISB is developing and qualifying new specific power modules. These power modules are required to utilize the full potential of modern power semiconductors in multi-level systems. By using specially adopted joining technologies the system lifetime is increased compared to state-of-the-art modules. New application-specific power module concepts allow the integration of protection mechanisms to improve the converter behavior and availability in case of system or device failures.
Control of Multi-level Converters
One drawback of multi-level topology concepts is the increased number of semiconductor switches to be controlled. Especially for systems with small and medium power, the control effort can represent a significant proportion of the total system cost. Fraunhofer IISB is developing optimized control and communication systems as key elements for cost-efficient multi-level systems. The work is focused on:
- Innovative communication concepts for cell based multi-level systems
- Development of control boards and decentralized control solutions
- Optimized IGBT and MOSFET drivers with special functions for multi-level control