In the high-stress world of today’s system power design engineer, defining the optimal strategy of the selection of high voltage power supplies (HVPS) can be daunting, because cost-effectiveness, need fulfillment, and overall operations are fully reliant on that selection. The benefits of HVPS are understood, which include a wide range of flexible options (such as a variety of installations, compact form factors, and miniaturization), all promoting ease of use. Despite this recognition, however, engineers are often not fully aware of the three common HVPS options available to them and that selection is not a one-size-fits-all
Handling Design In-House
Upon initial consideration, opting for in-house design of an HVPS can appear as a rational approach to manufacturing cost advantages and perhaps even performance advantages. After all, it is thought that in-house means a full understanding of process mission criticality, the specific high-voltage needs required for applications, and the nuances of both design and manufacturing. As in any industry, there are niche applications around which a firm’s competitive advantages are built using vertical integration. This can work for companies who have sufficient scale and depth of expertise that will provide the economics to support the cost of the approach.
However, in cases where multiple, competitive options exist that can satisfy the requirements of a firm’s needs, a “purchase” versus “make” decision is likely a better economic option. As is the case in all areas of the high-tech space, the current state of the art in modern HVPS is complex and the range and sophistication of the options available advances rapidly, parallel with that of the underlying high-tech industries that support them. Over the past 50-plus years, a tier of HVPS component suppliers has emerged to provide broad technical experience across multiple industries and in many different applications to provide economical, off-the-shelf, and semi-customized HVPS solutions for companies choosing to develop their differentiated value in other areas of the products they design, build, and distribute.
These suppliers support OEMs in complex applications such as ion-implant, mass spectroscopy, and scanning electron microscopes, to name a few. The competencies, manufacturing volumes, and decades of experience enable the OEM to focus on advancing the core capabilities their firm has been built around.
Purchasing a Third-Party, Off-the-Shelf Product
There’s no doubt that a strong advantage to utilizing a third-party off-the-shelf product is what appears to be a quick and easy purchase. With time-to-market fully tied to hard timelines with often little room for flexibility, off-the-shelf products can be a strong support, with the potential for highly accelerating time-to-market and dramatically improving field reliability and performance flexibility.
Suppliers specializing in the design and manufacture of HVPS components have developed decades of expertise that enable them to provide a range of solutions that address today’s high-voltage applications. Some examples include ultra-low ripple, fast/adjustable slew rate, current limiting or voltage regulation protections, maximum efficiencies over the loading levels desired, and digital metrology, controls, and communications.
Partnering with an HVPS Module Specialist
By partnering with an HVPS module specialist, engineers are provided with expert guidance in selecting the appropriate off-the-shelf solution or benefit from a custom design. The depth of experience brought by the right partner reduces project risks, improves equipment performance, and reduces overall costs. If the HVPS has a high degree of complexity and its end performance and configuration is not fully understood at the beginning of the product development project, the HVPS design/manufacturing expert can absorb this risk, freeing the larger system designer to focus on the core value proposition they have established in the markets they serve. As the design evolves and requires additional features or functionality, the HVPS team can develop these in parallel with the larger overall system design project.
Considering Total Cost
One example of the value a HVPS provides: In aerospace applications using piezo actuators, high voltage is necessary. A company that previously purchased third-party, off-the-shelf power supplies to support those voltage needs decided to investigate other approaches to better scale. They opted to hire an electrical engineer to design an HVPS with weight, voltage, and current—all critical parameters. A mechanical design engineer was also hired to design packaging suitable to manage high voltage (which included handling radiation immunity and high voltage discharges). These engineers were able to design an HVPS that, at first blush, met the basic requirements.
The freshly designed HVPS was then sent to a contract manufacturer to build prototypes. Unfortunately, because no existing purchased component infrastructure was available, low volume quantities of the components used were costly. Tooling was needed to fabricate the mechanical housing which, once built, required the designing/building of specialized equipment to test. Once the prototypes were built, testing was inadequate because the engineers hired did not account for the nuances of high voltage design, such as line regulation, ripple performance, noise immunity, high voltage tracing, and partial discharges. Significant investment—in both dollars, talent, and time—had been made, and the company was no closer to having an operational HVPS design.
The company then realized that additional hurdles and costs remained, even with an operational design in hand: certification of the HVPS design, UL and EMC testing (provided they knew what needed to be tested to qualify the high voltage design), ongoing yearly safety certification, and the ongoing maintenance of the components within the system. What’s more, they still owned legal liability if the HVPS failed in the application.
As a result, the company opted to reach out to an HVPS module specialist who was able to offer the proper guidance as to the appropriate third-party, off-the-shelf product to purchase, as well as provide counsel regarding the importance of understanding total cost: that it extends far beyond purchase price and an engineer’s time to design an alternative. Moving forward, the company turned to the HVPS module specialist for all application needs.
Utilizing a highly reliable HVPS module is only part of the support that engineers are typically looking for when designing their application systems. Being able to partner with a supplier that produces the modules who can also act as a thoughtful, independent design advisor is critical. Suppliers that have deep expertise in relevant applications add significant value to the end customer design process—whether that is providing guidance on initial module selection, design customization and iteration through the development process, or prompt, reliable fast delivery in full production stage.
In addition to this and under certain circumstances, standard modules can be quickly customized (without affecting approvals or safety certification) to meet individual application requirements. This can add great value to the end-system design cycle, minimizing both development time and costs.