Nanosatellites

8 I-2gPower Systems

Marcos Compadre¹, Ausias Garrigós², and Andrew Strain³

¹Power Systems Design Authority, Clyde Space LTD, Glasgow, UK

²Industrial Electronics Research Group, Miguel Hernández University of Elche, Spain

³CTO, Clyde Space LTD, Glasgow, UK

8.1 Introduction

The power system of a satellite performs some major functions within the mission: power generation, power distribution, energy storage, and power control. These functions are vital to the spacecraft, as they provide the electrical needs for the rest of the spacecraft subsystems, including the payload.

A simplified architecture of such a power system is shown in Figure 8.1. The main blocks are:

• The solar arrays (SAs) convert sunlight energy into electrical energy.
• The battery charge regulators (BCRs) are used to charge the battery from the solar arrays.
• The power conditioning modules (PCMs) are used to provide regulated and unregulated voltages to the spacecraft subsystems.
• The power distribution module (PDM) is used to safely distribute power to the different subsystems.
• The battery (BAT) stores the energy required when the power generated by the solar arrays is scarce, especially during eclipse.

The power system of a nanosatellite, shown in Figure 8.2, is also known as the electrical power system (EPS). In a typical nanosatellite, the basic elements of the EPS should be organized in an electrical architecture to obtain high efficiency, low volume, low mass, and low price. These challenging requirements force ...