Is the automotive industry ready for modular power systems and 48V batteries?

Here's what you'll learn:

■ How electric vehicle manufacturers can learn from modular automotive infotainment systems and apply them to powertrains.

■ Why using 48V batteries helps electric vehicle designers improve power efficiency and reduce power consumption while reducing vehicle weight.

Given the long and complex design cycles of the automotive industry, automotive technology development roadmaps are difficult to predict. Unlike other purchases, owning a car is an expensive, long-term investment that reinforces a methodical and rigorous mindset when it comes to industry risk-taking and cutting-edge innovative approaches.

That said, over the next three to five years, we will see two electrification trends: the increasing popularity of modular power supplies and the unstoppable adoption of 48V battery technology . Both trends are driven by OEM competition to electrify vehicles .

Let’s analyze each trend. Modular design reduces development complexity, simplifies supply chain management and inventory costs, and accelerates time to revenue. For example, if your car's infotainment system malfunctions, the dealer won't send someone to fix the radio. They will remove the center console and replace the entire front unit.

With the largest car companies launching as many as 15 different models in a given three-year period, the transition to interchangeable designs will continue.

Power supply and powertrain engineers have begun to borrow this strategy, reusing the same core design across multiple automotive platforms with different features and price points. This will become increasingly apparent as the proportion of vehicles with electrical systems rises from about 34% today to more than 50% in the next few years.

For example, high-density power modules help reduce packaging space and weight, which can increase driving range. And more modular technologies will drive this change, including steer-by-wire and brake-by-wire, which are powered by electrical systems rather than alternators. These technologies replace mechanical components with batteries, wired control systems and actuators.

Figure 1: Vicor power modules provide the power density, efficiency and flexibility to support and expand next-generation xEV power supply networks.

That explains why the top three U.S. automakers last year pledged to spend $100 billion developing new vehicle platforms, laying off thousands of mechanical engineers and scrambling to find electrical engineers and electrification experts to take their place.

The automotive industry's love affair with the ubiquitous 12V battery remains undiminished. For example, last winter, a large number of car and truck owners inadvertently benefited from the cold-crank performance of 12V lead-acid batteries. Its chemical composition ensures that the vehicle can start in severe cold conditions, which is not possible with 48V lithium-ion batteries. Even so, the case for enhancing certain applications with 48V alternatives continues to grow.

In recent years, we have seen the adoption of 48V batteries begin to climb, especially in small ancillary components such as fans, blowers and cryocoolers. Or take active suspension, a complex electronic circuit that compensates for changes in a vehicle's weight.

When you're driving 60 mph on the highway, the duty cycle of these systems is extremely low, but when you hit the off-ramp, the weight changes and the active suspension delivers plenty of current to push the power Levels increase to peaks of 4 or 5kW. Doing this on a 12V battery requires a lot of current, which in turn requires a lot of wiring and wiring harnesses. The same is true for water pumps, where the 12V power supply may require up to 9 meters of cable due to factors such as stray field immunity, leakage, voids and electromagnetic interference.

As a result, many of the latest emerging automotive subsystems tend to use 48V batteries, whose cables weigh 23 grams, only 10% of the equivalent 12V battery. By using thinner and lighter wire harnesses and cables, a 48V busbar can be implemented throughout the vehicle, thereby reducing weight and increasing cruising range.

Figure 2: Using Vicor bidirectional NBMs and BCMs , designers can efficiently convert high voltage supplies between 800, 48 and 12V .

OEMs are now focusing on reducing the weight of the in-vehicle wiring harness, which now weighs over 150 pounds, and can be significantly reduced simply by replacing it with lighter 48V cables. Having said that, the cost and sheer investment required to convert factory floors from 12V to 48V remains daunting for many automakers, tier 1 suppliers and component manufacturers who are already surrounded by an ongoing Older technologies that reduce costs build the entire power infrastructure.

However, higher efficiency and lower power consumption create indisputable conditions for switching to 48V power modules and busbars. The 12V status quo will soon be over, and automakers that refuse to respond to this trend will pay a heavy price at some point in the future.