The NANOeps is a comprehensive Electrical Power System (EPS) based on several innovative technologies for more efficient charging capabilities, which in combination with integrated three-level FDIR policy assure robust and reliable operation. It includes an innovative Analogue Maximum Power Point Tracking algorithm with reliability, excellent performance under dynamic conditions and high efficiency, and an cutting edge analogue battery balancing unit to gain optimum battery charging to significantly extend the batteries' life-time.
The NANOeps provides fully controlled and monitored regulated power rails to the satellite subsystems. The integrated data handling provides system level FDIR and full control via the hot redundant CAN interface and the Direct Command Interface.
Features
The NANOeps is responsible for managing all power related tasks on board the satellite. It manages the charging of the batteries using Analogue Maximum Power Point tracking units and a highly efficient balancing circuit. In addition to the standard temperature control of the batteries, the NANOeps integrates an independent thermal protection unit to ensure reliable operation even in faulty conditions. The batteries are over-voltage and under-voltage as well as overcurrent protected, while all battery cells and subsystem components are constantly monitored and available as housekeeping telemetry data on all interfaces. The distributed power rails are regulated by protected DC/DC converters. Each distributed power rail is constantly monitored and is individually protected by a configurable system level current limitation switch, where full telemetry is available via hot redundant CAN buss and Direct Command Interface. The integrated three-level FDIR policy assures the high reliability of the NANOeps subsystem including the system level FDIR to mitigate system level errors. The Direct Command Interface provides additional fly-by-wire control and telemetry without the intervention of any onboard data handling functionality, which can be used by operators to take control of the spacecraft in the case of a non-mitigated error. The integrated batteries are based on lithium iron phosphate (LiFePO4) technology in order to provide a longer life time and greater robustness. One important advantage over other lithium polymer (LiPo) and other lithium-ion chemistries is the thermal and chemical stability, which improves battery safety.
Features:
- State of the art highly reliable and efficient AMPPT
- Redundant design – individual tracking module per solar panel
- High efficiency even in dynamic conditions
- Passive battery balancing by design with integrated battery heaters
- Batteries have several protection mechanisms, including overvoltage, over-discharge, overcurrent, and temperature stabilisation to prevent under temperature
- Battery resistant to thermal runaway
- Higher discharging and charging battery pack currents compared with other conventional lithium-ion chemistries
- Battery lifetime of 2000 charge cycles (20% capacity drop) - 2 years in LEO
- Integrated 5V output power converters
- Individual power rail monitoring and control via TM/TC
- Power switches and current monitors on each rail
- Comprehensive local subsystem telemetry
- Hot redundant CAN interface for TM/TC
- Direct Command Interface for power cycling of each subsystem
Technical specifications:
| Solar panel inputs: | 4 x 10 W AMMPT (3U solar panel input) |
| Output channels: | 5 x 15W at 5V power rails |
| Battery: | 3 x LiFePO4 batteries |
| Nominal battery capacity: | 30 Wh (3300 mAh) |
| Nominal battery voltage: | 11 V to 8.4 V |
| Maximal charging current: | 1C |
| Maximal discharge current: | 4C |
| Dimensions: | 95 x 91 x 54 mm |
| Output power: | 490 g |
Part number:
| NANOeps 30Wh battery pack | nano-eps-30w-1 |
