Combined Inverter and DC/DC Converter delivers more for less in one revolutionary package.
On your path to more electrified vehicles, you’re likely to encounter a few detours as you struggle to find the power you need to propel the vehicle, along with its safety, convenience and autonomous functions. This path to power is probably a bit rough given obstacles such as weight, range, heat and space. It’s a series of wrong turns that often leads to a dead end.
Now, what if there was a single device that could help you avoid the obstacles and get you back on the right track? Something suitable for plug-in hybrids (PHEV) and electric vehicles (EV) that you can scale up as your power needs increase? If this is the direction you’re headed, then we’ve got your best route: Our Combined Inverter and DC/DC Converter (CIDD). This revolutionary device marries the inverter and DC/DC converter into one unit that ups power density and lowers weight, size and costs.
Think of it as the perfect combination of ingenuity and elegance that delivers more for less.
Inverter and converter basics.
Let’s cover a few basics before we get to how we created the CIDD. Much like how engines and alternators work together on conventional vehicles, hybrid and EV motors use inverters and converters to manage power to and from the battery pack to the motors and other on-board systems.
Inverters transform direct current (DC) from the battery into alternating current (AC) to power the vehicle. Inverters also control the motor and convert it to generator, transferring braking energy back into the battery. Converters control the DC voltage from the battery, either stepping it up or down based on the system and the power needed. DC/DC converters usually step down the high voltage from the battery pack to the 12-volts used by radios, headlights and more. Working in tandem, the devices manage the vehicle's electric drive and accessory systems.
Simple, right? Well, there are some drawbacks. Many of today’s inverters and converters can be complex, expensive and prone to failure. Heat is their biggest enemy. They also take up a lot of room – bulk on the vehicle that compromises both trunk and passenger compartment space.
So – what to do? At Delphi Technologies, we decided to merge the two to bring to market a first-of-its-kind, sleek, complete unit, which when compared to separate devices significantly cuts unit weight and size, boosts power densities and shaves costs.
Talk about a mind-blowing merger!
The road we traveled.
In developing the CIDD, there were three major customer pain points we knew we had to address to create the perfect combination.
As power and voltage needs on PHEVs and EVs increase, batteries, motors and supporting power electronics grow in size. This translates into the need for more space to package everything on the vehicle. Managing the power-to-size issue becomes especially tricky on hybrids since electrification components must be squeezed in around the traditional gasoline or diesel vehicle elements. Making vehicles bigger is rarely is the option, so space is commonly grabbed from the interior and trunk. Packaging also covers location, which is key to overall power strength. Simply put – The closer to the power source the less potential for power to drain through the cables. And, it involves heat. Two sources must be managed here: The internal heat generated by the devices in the power creation process; and the external heat generated by adjacent components and systems based on where the devices are positioned on the vehicle.
Our goal: Create something smaller, with fewer cables that could withstand the heat and be better positioned to power sources.
Beyond managing sticker-shock on hybrids and electrics, cost is a factor in capitalizing on government incentives aimed at closing the price gap between electrified and internal combustion vehicles. And, one of the biggest, overall cost drivers is the inverter.
Our goal: At minimum, avoid adding new costs to the combination device and, if possible, find ways to bring the total price tag down.
Hitting regulatory targets means landing the right portfolio mix of hybrids and electrics. Within each architecture, different voltage and current levels are often deployed to accommodate existing – and horizon – options and upgrades. All this variation creates a lack of platform level component standardization, and supply chain fragmentation. It also makes it difficult to leverage base technologies for future needs.
Our goal: Provide a single solution that could be used across varying portfolios, option packages and had room to grow.
In developing our solution, we leveraged our Viper-enabled inverter technology. Viper’s patented, double-sided cooling reduces heat, allowing higher power outputs from a smaller package that increases range. And, it's silicon carbide base can be easily scaled up or down to accommodate different voltage levels and current outputs. The combination of its low profile, market-leading size, scalability, range and thermal management capabilities made Viper ideal to pair with the DC/DC converter.
As we moved through development, even more ground was gained on our goals as we pulled in the DC/DC converter. The combined unit:
- Provides maximum packaging flexibility and space savings by moving the DC/DC unit from its standard location in the rear to the front of the vehicle. In fact, we are currently the only supplier to deliver a combined unit that works under the hood.
- Enhances durability and reliability through features designed to withstand punishing under the hood and external environmental factors that include debris and temperature extremes.
- Improves voltage distribution functionality, enabling both low-side and high-side power for everything from headlights to power steering and air conditioning systems.
- Boosts cost savings, manufacturability and serviceability, as well as enabling better power range and minimizing power losses through the elimination of cabling, cooling hoses, connections and housings.
Given our success with the CIDD, we’re continuing to pave new roads in combination power electronics advances. Our next revolution, already in development, blends the inverter, DC/DC converter and the on-board charger into an “all-in-one-box.” Another first-of-its kind innovation, the all-in-one further reduces size, complexity and more importantly, costs. Current projections indicate it could shave as much as $1,000 off future electrified vehicles.