ELFIN’s power system is a network of electrical components used to supply, transmit, and consume electric power. The scientific payload, ADCS, command and data handling boards, actuators and radios all have specific voltage and current requirements that must be serviced at different times, dependent on the orbit and mission requirements. Per the design, ELFIN has a 60% power margin against the battery specifications, after itemized contingencies. Careful analysis is also given toward the Energy consumption during orbits in eclipse, with specific requirements. For the longevity of the batteries, discharge and charge cycles must be kept at a minimum. Care must also be taken in predicting the power consumed by the torquer coils for repositioning.
The ELFIN Power system has been designed to provide sufficient power to the systems throughout the entire life of the spacecraft. The system includes Spectrolab UTJ cells and rechargeable Lithium-Ion batteries. These components are controlled by PIC microcontrollers to provide proper power to each of the other systems during the ELFIN mission.
For determining our power budget, we allocated the total power our solar panels would be able to generate in three different orbits based on our beta angle with the sun. Our budget with the lowest power allocated is our beta zero case; here we need to heat our batteries and cannot power our payload. Only when we reach a beta angle of 15° can we exclude heating our batteries and take science data. The budget is provided below and in this excel page: ELFIN Power Budget