Current large passenger aircrafts use low voltage (below 1kVac rms or 1.5kVdc) distribution systems to transmit a relatively modest amount of power (below 1MW) for use in aircraft subsystems such as cabin conditioning and actuation. The existing power distribution systems often use the metallic airframe as the earthing system.
In the future, all electric aircrafts will need higher voltages to meet the increased needs for higher efficiency and power density.
With an increase in the predicted demand for high voltage electrical power in large passenger aircraft and other more electric aircraft concepts, new electrical distribution systems will be required to enable safe, light, highly efficient electrical propulsion systems.
To make electric or hybrid propulsion systems feasible, greater electrical power transmission at high voltage will be required. These higher voltage, however, create additional stresses to the electrical insulation of cables, electrical machines and components.
Monitoring the state of health of the insulation and detecting faults becomes crucial in safety critical systems such as aircrafts' power systems.
High power electrical systems in high reliability applications often utilise IT (Isolation Terra) earthing. IT earthing brings known advantages of fault current management and continued operation post fault. It also brings the challenge of correctly determining when an insulation fault has occurred, allowing the system to safely reconfigure or shutdown.
Despite their importance, insulation monitoring technologies have not been tested, proven, optimised and made commercially available for aerospace applications.
IMITAES has designed, optimised and increased the Technology Manufacturing level of innovative insulation monitoring systems specifically based on the requirements of the aerospace sector.