This article based on Knowles Precision Devices blog explains the role of supercapacitors in no-fail back up power supply systems and its benefits over the battery powered modules.
With more and more mission-critical systems relying on electrical power, consistent and reliable backup power is essential to ensure uninterrupted operation.
Facilities like data centers and hospitals leverage backup power to manage the short, but potentially catastrophic, delay between grid power failure and the start of long-term back up (e.g., local generation via diesel generators).
In addition to maintaining life sustaining functions, hospitals leverage backup power for managing portable devices that rely on variable power (e.g., portable MRI). In smart buildings and factories, backup power ensures actuator operation, so valves and baffles can return to a safe position. Similarly, grids have smart reclosers that can isolate sections of a line to guarantee safe operation and communicate line status updates after a transient fault.
Short-term and long-term backup power sources are critical layers of protection. While batteries are useful in some backup functions, they present disadvantages in the scenarios above. With limited runtime, capacity degradation concerns and limited power surge capabilities, they’re not designed to provide those quick bursts of energy needed to bridge the gap between failure and local power generation.
Supercapacitors, or ultracapacitors, are energy storage and delivery devices with extremely high capacitance—millions of times more capacitance than traditional capacitors. They are an asset in modern power management because they’re designed for reliable, rapid responses for hundreds of thousands to millions of duty cycles, even under demanding environmental conditions.
With an array of sizes, supercapacitor modules, where supercapacitors are arranged in series or parallel configurations, offer real-time backup power supplements for mission-critical systems. In the right configuration, they can deliver a response at scale to address a surge or outage.
While it’s possible to design and implement your own supercapacitor modules, thermal management and cell balancing present complexities that could explode your design scope. To support your development efforts, Knowles Precision Devices offers a range of supercapacitor technologies that serve as the basis for custom modules.
Whether you’re looking for a custom or off-the-shelf option, here are some questions you’ll need to answer before selecting the supercapacitor technology, cell arrangement and balancing approach for your module:
- What’s the minimum voltage level the system needs to maintain?
- How much time do you need to maintain that minimum voltage before long-term backup power kicks in?
- What voltage level is available for module charging during normal system operation?
- What current and power levels must your system be able to support?
- What are your anticipated lifetime requirements?
- What are your most stringent mechanical constraints (e.g., size)?
- What environmental or thermal conditions will the system operate under?
If you’re interested in a custom module, here’s Knowles SCM design form.
