How to Choose the Right Power Partner for Medical System Design – Free White Paper

Precise and appropriate power conversion plays a crucial role in medical system development but is often considered too late in the design cycle. This can lead to significant consequences such as delays in certification time and increased development and system costs.

 

Bringing power considerations forward helps teams avoid these downstream impacts and it also unlocks new capabilities earlier in the program. Especially for medical applications, choosing the best power supply enables the introduction of advanced techniques, for example control, monitoring and communications functionality or the addition of artificial intelligence (AI) into medical imaging systems. Early decisions related to the power supply also allow for the creation of more complex, highly integrated systems, and (of course) the development of smaller form factors that bring improved portability.

 

This is true for most systems, but in medical equipment it is critical, as power systems are tightly regulated through multiple medical device standards. The EN60601-1 safety standard, for example, sets exceptionally tight requirements on leakage current for systems that have patient and operator contact. This includes three classes of contact: body (B), body-float (BF) and cardiac-float (CF). There are also other regulatory standards, such as EN55011, that place stringent electromagnetic interference (EMI) limits to ensure that multiple medical systems can run close to each other within a hospital setting.

 

One of the most important steps to take, therefore, is to consider power at the start of the design cycle. Doing so enables these tight requirements to be met, while also balancing costs and accelerating time to market.

 

Some of the benefits of choosing the power supply earlier in the design process include:

 

Whether for a pre-certified standard product, a modified standard part, or a custom power supply, choosing the right power partner will help ensure requirements and risk management are met, and necessary risk analyses are carried out – as is required by EN60601-1.

 

In addition, other issues can be solved quickly without significant redesign. One example involves a case study where an Advanced Energy (AE) customer used the Xgen series of medical power supplies in an application with high capacitive loading.

 

For this customer it was observed that the high capacitance was forcing energy back into the unit on shut down. This in turn triggered Xgen’s negative current limit and created high voltage peaks (see figure 1, below), with the system interpreting these peaks as over-voltage events. A protective latch was initiated, and the system could not restart for two minutes.

This is far from ideal. In this case, a close, transparent relationship between the power supply design team and the customer’s system design team can mean the difference between a complete redesign and a simple modification. In this case AE was able to do the latter. The AE team identified the root cause, proposed a range of solutions, and (in agreement with the customer) implemented an internal modification to the Xgen’s over-voltage trigger levels that resolved the issue without affecting the original projected timeline.

 

The key point to resolving the issue quickly was based on the working relationships and the trust built between the two companies, with engineering staff from both sides having a clear understanding of the issue, and the communication to correct it.

 

There are steps to finding the right power partner, and this is the subject of AE’s white paper referenced below. The white paper can be downloaded for free and includes information on:

To find out more, please reach out to Advanced Energy here, or you can download the free white paper by clicking: Choosing the Right Power Partner | Advanced Energy.