When you think about power supply design, it’s easy to focus on semiconductors, circuits, and system control. But behind every efficient, reliable power conversion system lies one of the most critical, and often most challenging, elements: “magnetics.”
Magnetics form the heart of every power supply, converting voltage/current, filtering noise, and storing energy. At Advanced Conversion Technology (ACT), our ability to custom design and manufacture magnetics in-house is one of the key reasons our power supplies deliver exceptional performance in demanding military environments.
Let’s look at how magnetics work, why they matter, and how ACT’s specialized design expertise gives customers a measurable edge in performance, size, and reliability.
In simple terms, magnetics control how energy moves. Within a power supply, components like inductors, transformers, and common-mode chokes perform three primary functions:
In Switch Mode Power Supplies (SMPS), these functions are essential for maintaining efficiency, managing electromagnetic interference (EMI), and protecting downstream electronics.
That’s why ACT engineers regard magnetics as a major building block of a power supply. Without them, you can’t achieve the performance or reliability that mission-critical systems demand.
For electrical engineers, magnetics design is one of those disciplines where theory meets real-world engineering tradeoffs. The choices you make with core materials, wire types, winding methods, and geometry, can define the overall success of your design.
Magnetics is also a niche area of expertise. Few engineers specialize in it, yet it can make or break a design. Having resident experts, like those at ACT, means customers benefit from decades of accumulated knowledge, simulation tools, and hands-on experience.
Designing magnetics is largely about minimizing energy loss. Every watt lost to heat is a watt not delivered to the load. Two primary types of losses occur in magnetic cores and windings:
Core Loss: Core loss occurs in the magnetic material itself and has two main attributes:
The material choice makes a big difference here. For example, powdered cores like MPP help reduce eddy currents compared to laminated iron cores, keeping losses lower at high frequencies.
Copper Loss: Copper losses occur in the windings that carry current. With DC, this is simple- power loss equals the current squared times the wire’s resistance (I²R). But at high frequencies, AC copper losses become more complex due to two phenomena:
These effects are why magnetic design at ACT isn’t just about picking a wire gauge; it’s about carefully choosing materials and winding methods to manage these losses while balancing cost, performance, and manufacturability.
ACT uses a variety of wire types depending on design requirements:
While Litz wire can reduce AC losses significantly, it’s also more expensive to produce. That’s where ACT’s experience pays off: ACT engineers know when the performance gain justifies the cost and when other design optimizations can achieve the same result.
No magnetic design is perfect because some magnetic field lines always “leak” at the edges of cores or through air gaps. These fringing fields can induce additional losses or unwanted coupling. ACT’s engineers mitigate these effects through careful design of core geometry, minimal core gaps, and winding techniques to reduce parasitic losses and ensure consistent performance even under demanding conditions.
One of ACT’s key differentiators is our in-house magnetic design and manufacturing capability. While many power supply manufacturers rely on third parties for transformers and inductors, ACT builds nearly all its magnetics internally using in-house tools and capabilities.
This vertical integration means ACT can move fast to prototype, test, and refine magnetic designs to achieve the best possible balance of performance and size. It also ensures tighter quality control and long-term supply consistency for customers operating in demanding industries.
Military and industrial systems often come with strict volume and weight constraints. A magnetic designer must find innovative ways to meet electrical specifications without exceeding physical limits. ACT’s engineers use advanced methods such as:
These design techniques have enabled ACT to develop magnetics for some of the most demanding defense applications including compact airborne systems and high-reliability shipboard converters.
For electrical engineers evaluating suppliers, ACT’s in-house magnetic design capability translates into a number of practical advantages for the power supply ACT will be designing for the customer. Improved performance is a key advantage when magnetics are optimized for low loss and high efficiency.
Reliability and speed are other advantages. Proven designs that meet or exceed MIL-STD and industrial specs deliver high levels of reliability. And rapid prototyping and in-house iteration reduce lead times.
Customization is another benefit that ACT can deliver with tailored solutions for challenging electrical, thermal, or mechanical requirements.
Ultimately, with over 40 years of experience, ACT combines deep technical expertise with modern manufacturing tools, ensuring magnetic components perform as required.
Magnetics may not be the flashiest part of a power supply, but they are critical. The efficiency, size, and reliability of the entire system can hinge on how well inductors and transformers are designed and built.
At ACT, we take pride in mastering that art. Our engineers combine decades of practical experience with modern materials and manufacturing methods to deliver magnetics that reliably operate in mission-critical environments.
Whether you’re developing a ruggedized military converter or power system where failure is not an option, ACT’s custom magnetic design ensures your power supply performs as intended from the inside out.
Contact us today to partner in power!
