It has been over 30 years since Zarya, the first module of the International Space Station, was launched. And in November 2000, the first human crew arrived. This deployment has been a success on many fronts, including the stand-alone power system. Although fuel is required to provide thrust and maintain its orbit, all electrical systems are supplied either by solar energy or storage batteries. The station’s solar array can provide enough power to supply nearly 40 homes, which is more than sufficient to meet its energy needs and maintain ample storage.
Maintaining life support systems, laboratories and other essential electrical and electronic equipment can be a challenge, though, as these systems also produce heat. Here on Earth, typically we are concerned only with removing excess heat from electronic systems and the boards that comprise them. However, ISS operation focuses on efficiency; instead of simply wasting energy, much of it is captured and reused. Energy harvesting PCBs are designed for this purpose and contribute significantly to aerospace system efficiency and operational lifecycle reliability.
Supplying vs. Harvesting Energy
Circuit boards commonly supply power to other boards, devices or electronic systems. These power supplies fall into two major classifications.
Types of Power Supplies
- Linear power supplies
Typically used for communications, industrial equipment, control systems and laboratory equipment.
- Switch-mode power supplies
Used in computers, telecommunications devices, phone chargers, arc welding and other equipment.
For power supplies, delivering energy at the proper level for the load is the principal objective, and any excess heat generated has to be removed.
Energy harvesting, sometimes referred to as energy scavenging, can be defined as follows:
Energy harvesting is the process by which energy present in the environment is harnessed, converted and utilized as an additional source of supply for the system.
There are many examples of energy harvesting. For instance, renewable wind and solar energy add robustness to grid power supply systems around the globe. Energy harvesting can also be implemented on a smaller scale through components such as energy harvesting PCBs.
PCBA Manufacturing for Extreme Environments - Part 1
How Circuit Boards Harvest Energy
The essential functionality of an energy harvesting PCB is shown in the figure above. As illustrated, these boards typically harness from one of three source types.
Energy Harvesting PCB Types
These PCBAs utilize the Seebeck effect, where a temperature differential creates a corresponding voltage potential that can be used as a direct electrical source or stored—for example, to recharge a battery. Thermocouples and Peltier devices are the primary harvesting components.
The photovoltaic effect describes the conversion of light into electrical current, which is the function of solar cells, the foundational elements of solar energy systems.
Piezotronics boards are often used in aerospace systems. These boards contain components that exhibit the natural piezoelectric effect, where a change in external pressure results in a change in electrical charge.
Although these board types are deployed in terrestrial systems, they are used more widely in aerospace applications.
Why Are Energy Harvesting PCBs Important for Aerospace?
Aerospace is a harsh environment, and there are many significant challenges when deploying spacecraft. Unmanned space vehicles, such as satellites, must fulfill mission requirements for years without needing maintenance or repair. Consequently, aerospace PCBAs must be developed to achieve consistent functionality and reliability that matches or exceeds the requirements for all other circuit boards.
Energy harvesting PCBs can improve the efficiency of aerospace boards by removing excess heat and maintaining the thermal control required aboard manned and unmanned spacecraft. These boards also help sustain energy backup or storage capacities since less power is needed for the boards to operate.
Efficient energy usage is a significant issue aboard spacecraft. And boards that maximize power utilization efficiency must be reliable. Tempo Automation, the industry leader for fast, high-quality PCBA manufacturing for prototypes and low-volume production, is experienced in building boards that successfully meet the requirements for space deployment.
And to help you get started on the best path, we furnish information for your DFM checks and enable you to easily view and download DRC files. If you’re an Altium Designer or Cadence Allegro user, you can simply add these files to your PCB design software. For Mentor Pads or other design packages, we furnish DRC information in other CAD formats and Excel.
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