The idea of the electric vehicle is not new to today’s consumers. EVs have existed in a variety of forms for almost two centuries. In the past few decades, however, as technology has advanced and companies such as Tesla have found success—and as we grapple with the effects of climate change, air pollution, and an ever-decreasing supply of fossil fuels—more consumers are considering EVs than ever before. 

The growing popularity of EVs isn’t due solely to consumer demand. Governments around the world have increasingly issued regulations and mandates, such as the Paris Agreement, to reduce carbon emissions in an effort to curb global warming. 

By the end of 2020, one study estimated that there were 10 million electric cars in operation across the globe. In fact, electric-car registrations increased by 41% that year, even though worldwide car sales overall dropped by 16% due to the Covid-19 pandemic. The same study found that approximately 3 million electric cars were sold globally in 2020 and that Europe overtook China as the world’s largest EV market for the first time. 

Since then, the market for electric cars has grown steadily. Gartner has forecast that 6 million electric cars will be shipped in 2022, and some experts are estimating that global EV passenger car sales could make up roughly half of all cars sold by 2030 (Figure 1). Automakers around the world acknowledge this trend and are preparing to deliver what consumers want. For example, GM recently announced that it will stop making gasoline- and diesel-powered vehicles by 2035, and Audi plans to do the same by 2033. 

The skyrocketing rate of growth in the EV market presents a tremendous opportunity for EV manufacturers, OEMs, and aftermarket-part makers. While EV technologies and solutions have advanced significantly over the past couple of decades, there are still a few challenges that can quickly become roadblocks. A manufacturer’s success depends heavily on the development of new and innovative ways to address these challenges. 

Figure 1: Global EV passenger car sales could make up roughly half of all cars sold by 2030. 

Three important considerations: Overcoming EV challenges

When it comes to modern EVs manufactured over the past 20 years, there are three main reasons why most consumers haven’t considered them a viable option: 

  1. Range anxiety. The first modern EVs couldn’t go very far without needing a battery charge. The range was too small for people to seriously consider making the switch to fully electric vehicles. 
  1. Performance. Even in the early 2000s, EVs just couldn’t match the power and performance of gasoline-powered vehicles. 
  1. Cost. EVs were expensive. The first few Tesla models, for example, were far outside the typical price that most people were willing to pay. 

Today, we do see carmakers address some of these challenges, but the dream of a car that you charge only once a month, is affordable for most, and doesn’t compromise on performance is still elusive. The trick for manufacturers will be to balance the tradeoffs between range, performance, and cost. Juicing up performance can affect range and cost, for example, and cutting the cost of EVs could compromise performance and range. 

Here are some of the considerations that manufacturers must keep in mind as they address these challenges: 

Range: efficiency is key 

The primary bottleneck on improving range is battery capacity. A simple way to increase range is to use a bigger battery, but bigger batteries cost more, which increases the total vehicle cost. They also weigh more, which decreases performance. 

The key here is finding ways to make the existing battery more efficient. That means reducing the energy losses that occur naturally throughout the vehicle’s power-conversion systems. Just like a laptop power adapter radiates heat (lost energy), there are losses of energy in an EV’s powertrain, motor, and other power-electronic subsystems in the car. 

Performance: watch your weight 

Weight is one of the key factors in a car’s performance. Keeping the vehicle as lightweight as possible is a must. This is where power density comes into play — adding more power without adding weight. The smaller and lighter your batteries and power-conversion systems, the better speed and performance you can achieve. 

As technology improves, smaller form factors become possible. Smaller batteries and power-conversion systems could potentially offer the same range as standard batteries and systems but increase performance significantly. 

Another factor that affects performance is battery voltage. Some EV manufacturers use a 350- or 400-V battery, but batteries of 800 to 900 V are becoming more popular across the industry. When voltage is increased, the current needed to power the motor and other power subsystems is decreased. This allows you to reduce the thickness of the cables that carry the current from the battery to all of the car’s systems. Smaller cables reduce weight, which increases performance. 

Cost: turn efficiency into savings 

Battery technology is still very expensive, and car manufacturers must constantly juggle between range, weight, and price while choosing these technologies. 

Battery efficiency has a direct impact on cost, because if you’re using your existing battery more efficiently, you can increase the range without having to buy more battery power. The reduced size of cabling needed for higher-voltage batteries can reduce cost, too. 

Take, for example, the EV powertrain — the main subsystem that provides power to the motor. A 0.1% increase in the efficiency of the powertrain can save up to $500 in battery costs. New motor designs and efficient powertrain solutions can have a dramatic impact on the overall cost of the vehicle to the consumer. 

Vehicle-to-grid (V2G) is another technology that allows electric cars charging at homes to give back to the power grid. The V2G architecture doesn’t treat the 800-/900-V batteries as backup storage cells for the power grid and allows the EV owner to save money while converting car batteries into grid arrays. 

A look inside the EV power-conversion system 

Significantly improving range, performance, and cost essentially comes down to the limitations of power devices. Figure 2 presents a block diagram illustrating the basic operation of an EV and the primary power-conversion system components. The most important components for this discussion (in blue) are: 

  • The on-board charger, which allows connection to an external AC/DC charging station 
  • The DC/DC converter, which converts high-voltage battery DC to lower-voltage DC for internal electronics 
  • The main inverter, which converts high-voltage battery DC to three-phase AC that powers the motor 

Let’s take a closer look at each of these components. 

primary power-conversion system components in an EV.
Figure 2: The primary power-conversion system components in an EV 
On-board Charger characteristics.
DC/DC Converter characteristics.
Main Inverter characteristics.

The main inverter is the heart of the power-electronic system in an EV. In fact, the traction inverter powertrain has the most impact on an EV’s range, performance, and cost: The more efficient the powertrain, the better the range, performance, and cost. Powertrain efficiency is a combination of the efficiency of the inverter and the motor. Increasing inverter and motor efficiency can significantly reduce motor losses. 

The biggest causes of energy loss in motors are eddy currents, or loops of electrical current formed in conductors by a changing magnetic field, and an imperfect sine-wave AC input. A higher switching frequency can address both of these issues by reducing eddy-current losses arising from higher-order harmonics and improving the quality of sine-wave input to further reduce losses. 

Evolving applications require new solutions

Making real improvements to EV range, performance, and cost will take a new breed of power-conversion system. To meet growing market needs, EV manufacturers are looking to push vehicle designs by leveraging the latest technology innovations. These include higher-voltage 800-/900-V batteries, new requirements to increase vehicle robustness (such as short-circuit protection), and new motor designs that fully utilize the vehicle battery. The silicon-based power technology that enabled the explosion in consumer and industrial electronics in past decades is no longer sufficient for today’s advanced needs. Modern EVs require more advanced power semiconductor technology. 

NexGen GaN technology.
Figure 3: NexGen GaN technology 

NexGen Power Systems: Reinventing Power Electronics

NexGen is a vertically integrated company in power electronics that has achieved a fundamental breakthrough in power semiconductors, based on Vertical GaN technology, which has allowed the company to build the next generation of power systems based on its scalable, software-configurable power platforms. 

It all starts with gallium nitride, which is inherently superior to silicon and silicon carbide when it comes to making semiconductors. NexGen’s Vertical GaN semiconductors are the world’s first GaN-on-GaN solution. They’re 95% smaller than silicon-based systems and deliver: 

  • Low switching losses 
  • High switching frequency 
  • High energy density 

NexGen Vertical GaN devices have already proven themselves as the choice for EVs and other applications with several advantages, such as: 

  • Superior breakdown voltage and current capability for a given chip area than any other GaN device 
  • The only GaN technology that can deliver a breakdown voltage of 1.2 kV and above 
  • Absence of dynamic on-resistance due to the control principle of NexGen’s eMode device technology 
  • Reduced defect density in the GaN-on-GaN homoepitaxial layers 
  • Significantly lower output capacitance, which substantially reduces switching losses and enables high switching frequencies 

Ideal for high-voltage power electronics in electric cars, Vertical GaN–enabled power supplies can lower costs by reducing passive components like inductors and capacitors. The resulting power systems are not only lighter and smaller, but they are also more robust and efficient, making them ideal for applications with size and space constraints as well as cutting-edge efficiency and robustness requirements. 

NexGen engineers are working with car manufacturers to develop EV power-conversion systems to their unique specifications. The systems are scalable and software-configurable, so they can be adjusted to address the various power levels in a car by using the same core architecture. The company also provides EV manufacturers with Vertical GaN transistors that they can put in their proprietary inverters. 

Figure 4: NexGen provides next-generation power-conversion systems and transistors for EVs. 

NexGen provides next-generation power-conversion systems and transistors for EVs. 
Figure 4: NexGen provides next-generation power-conversion systems and transistors for EVs. 
Benefits of power systems with vertical GaN in EVs.

With state-of-the-art power systems based on the innovative Vertical GaN devices in your EV power-conversion systems and inverters, you can achieve improvements in all three major areas: range, performance, and cost. The power electronics in the EV will be significantly more efficient and provide consumers with the driving experience they desire. 

Making a global impact

Overall efficiency improvements also present a significant opportunity for a greater global impact. 

An average EV requires 30 kWh to travel 100 miles. Assuming a typical vehicle drives an average of 13,500 miles in a year, this amounts to 4,050 kWh of energy consumption in one year. An estimated 150 million EVs are expected to be sold from 2025 to 2030. Assuming a typical 11-year ownership of a car, the electricity consumption of these new vehicles is estimated to be approximately 6.6 trillion kWh. A 1% efficiency improvement in the overall EV power electronics of these cars amounts to 66 billion kWh of energy savings. This is equivalent to the carbon sequestered by one-third of all U.S. national forests — or more than the annual energy consumption of New York City. 

GaN devices impact on the environment.
Figure 5: Using vertical GaN devices can have a significant impact on the environment. 

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