ESA: Electrical Power Conditioning Unit and System

Kurzfassung

An international organisation offers an improved electrical power conditioning unit (PCU) and system with reduced complexity, greater flexibility, increased efficiency and/or reduced mass compared to common architectures. The offered PCU is well suited for short charge-discharge periods with the total PCU efficiency exceeding 96 %. The technology owner is looking for partners for a licence agreement and for industrialising the technology.

Details

The offered electrical power conditioning unit (PCU) and system applies in particular, although not exclusively, to spacecraft systems, such as solar arrays. The main function of a PCU is to condition the energy coming from relevant power sources and to deliver it continuously to users in an appropriate form.

The offered technology aims at providing an improved PCU architecture with reduced complexity, greater flexibility, increased efficiency and/or reduced mass. This is achieved by the electrical PCU comprising a first and second terminal for connecting either an electrical power generator or a battery, and a third terminal for connecting a power bus comprising a reactive structure (RS), at least one output and one input switching structure. This PCU is included in a power conditioning system together with a control circuit including a current control loop using a current feedback signal for generating a PWM signal.

Up to five switches are implemented in the offered technology which can either be
- non-controllable switches, unidirectional in current, i.e. rectifiers such as diodes
- controllable switches, bidirectional in current, such as transistors, e.g. MFETs
- or controllable switches, unidirectional in current, such as a MFET connected in series with a diode.

Unidirectional switches can also be implemented by using synchronous rectifiers, having the advantage that they introduce a lower voltage drop than uncontrolled rectifiers.

Innovative Aspects:
An innovative aspect of the offered technology is that the input switching structure (ISWS) forms, with the RS a first DC/DC converter and the output switching structure (OSWS) forms with the same RS a second DC/DC converter. As the ISWS and OSWS share the same reactive elements, they have much lower mass and volume than two independent converters, which are used in conventional PCUs.

Moreover, by slightly modifying the switching structures, and without changing its topology, the offered PCU can be adapted to different operating conditions, which usually require completely different PCUs.

The presented technology is therefore simpler and more flexible than the prior art.

Furthermore, the total PCU efficiency exceeds 96 % in the case of both, a charged and discharged battery.
The offered technology allows minimising the losses, in particular the conduction losses, using a single converter based on a single RS. This leads to the very high efficiency value.