Electrical power conditioning unit and system
|559 - Abstract:|
|The European Space Agency (ESA) has developed an electrical Power Conditioning Unit (PCU) and system. The main function of a PCU is to condition the energy coming from the power sources (typically solar arrays and batteries) and to deliver it continuously to the users in an appropriate form during the overall mission. The offered PCU unit and system provide reduced complexity, greater flexibility, increased efficiency and/or reduced mass compared to common architectures. Partners for industrialization are sought.|
Description of the offer:
The offered technology relates to an electrical Power Conditioning Unit (PCU) and system, in particular for a regulated solar bus. The invention applies in particular, although not exclusively, to spacecraft power systems.
The most common structural designs for this system are the centralized regulated bus and cascaded regulator architecture, which provide several well-known advantages over un-regulated systems, namely the simplification of the user voltage interface, leading to simpler secondary converter designs, greater standardization of equipments, simpler electromagnetic cleanliness control (ECC) and flexibility and optimization of the battery and solar array design, which have more system mass impacts than the power conditioning equipment.
Centralized power regulated bus are rarely implemented for spacecrafts designed to operate in Low Earth Orbit (LEO). The traditional power electronics regulated bus architecture applied to LEO spacecraft would require heavy and large power converters, especially battery charge and discharge regulators. For this reason unregulated buses (directly connected to the battery, and therefore having a varying voltage level) are commonly implemented on LEO satellites, losing the advantages of the regulated bus.
For this reason the "converters in cascade" architecture is sometimes chosen to split the platform users and the pulsed power loads. Such architecture has been implemented on ESA Aeolus spacecraft in order to reduce the mass of the PCU versus the conventional regulated architecture.
The cascaded architecture provides lower efficiency than the centralized one. However, the cascaded architecture is easier to control than the centralized one, and avoids the use of too heavy converters in LEO applications.
Both architectures can be used with several PWM converters in order to achieve numerous benefits, namely the ability to operate the solar arrays at their maximum power point, with the help of maximum power point trackers to extract the power from the solar arrays, to manage the charge and discharge of the battery and to generate an external centralized regulated bus for other units.
Innovations and advantages
The offered technology aims at providing an improved PCU architecture with reduced complexity, greater flexibility, increased efficiency and/or reduced mass.
Furthermore, the present invention allows minimizing the losses, and in particular the conduction losses by using a single converter based on a single reactive structure. This leads to the very high efficiency values, as it has been experimentally verified in well documented laboratory studies.
Domains of Application
The PCU and system architecture of the offered technology, although particularly suited for space applications, can also be used in non-spatial, e.g. terrestrial applications where there is need for a improved PCU for short charge-discharge periods.
A particular field of expertise that could be interested in this technology would be on energy generating devices, namely on solar or wind energy, where several energy sources have to managed according to the availability of the original source of power.
Last update: 27 February 2013