Not most people know what a hybrid vehicle means, especially when it comes to differentiating a plug-in hybrid car from, say, a BEV or other types and subtypes of electric vehicles.
This article will help you understand plug-in hybrid electric vehicles (or PHEVs) better – what they are, how they work (especially how they charge and store power), and their pros and cons.
So, let’s start digging!
What Is a Hybrid Car?
Hybrid electric vehicles (or HEVs) use two powertrains – an electric motor and a petrol internal combustion engine (ICE).
The Bridge between Petrol and Electric Powertrains
You can say that hybrids are the halfway house between ICE and pure electric vehicles, and as such, they combine the best of both worlds.
Electric motors have efficient acceleration, delivering more power from a dead stop than do internal combustion engines.
However, they are limited by range because bigger batteries that could last long drives are bulkier and more expensive. That’s an issue with pure EVs but not with HEVs.
Hybrids get around with a relatively smaller battery pack because it works with a small but efficient petrol ICE.
As you very well know, not all HEVs are the same. In fact, they vary so much it’s easy to get confused. For this article, we focus on the PHEVs.
Plug-In Hybrid EVs (PHEVs)
PHEVs extend the hybridisation concept by using larger capacity batteries that can be recharged using an external electrical outlet or at a charging station. For short commutes, these EVs typically run using electricity.
The on-board engine can also charge the battery, but this is costlier than recharging via the grid. PHEVs can store more electric juice, such that their petrol usage is significantly reduced.
The thing here is that with PHEVs, range anxiety becomes less of an issue, if at all.
PHEVs have a system that allows emissions from the tailpipe to be displaced to the generators powering the grid. Depending on the car model, the generators can either be renewable or have a lower emission.
For example, Chevrolet’s extended-range EV Volt is a plug-in hybrid. For distances within the battery’s range, the Volt works as a full EV. Beyond, the car will switch to the gas engine.
Different Modes of Operation
Although all plug-in hybrids have an electric motor and a gas engine, they vary in operation, which is either of three different modes. They can be charge-sustaining, charge-depleting, or mixed-mode, which is a combination of both.
1. Charge-Depleting Mode
For the charge-depleting mode, the vehicle runs on electricity from the battery until it is depleted to a predetermined level. At this point, the car will then revert to and engage the gas engine for the rest of the drive.
The period where the vehicle runs (almost) exclusively on electricity is its all-electric range.
2. Charge-Sustaining Mode
For the charge-sustaining mode, the vehicle uses both petrol and electricity since the battery is recharging.
3. Blended Mode
Some hybrids make use of both modes - they can switch between the two modes depending on the driving conditions. Such hybrids are referred to as blended mode plug-ins.
Key Components of a Plug-In Hybrid EV
Even as PHEVs differ, they have a few key components common to all.
- Battery - provides electric power to start and keep the vehicle running. The battery also powers almost all the car accessories and systems.
- Charging Port - used to connect the car to an external electric outlet for recharging.
- DC to DC Converter - used to step down the high voltage from the battery to a lower voltage that car accessories need.
- Electric Generator - generates electricity from the braking action of the vehicle. The power is transferred back to the battery. The electric traction motor drives the wheels. Some car models use a motor-generator as it can handle both drive and regeneration functions.
- Fuel Tank - stores fuel that is used to power the vehicles when it reverts to the petrol engine.
- On-Board Charging System - used to charge the battery pack. It converts the AC electricity from the charge port to DC. It also monitors the battery conditions as well as performance parameters such as voltage, temperature, and current.
Configurations of Powertrains
The powertrains of PHEVs are similar to those of conventional hybrids. They include series, parallel, and series-parallel.
1. Series Hybrids
Only the electric motor turns the wheels of the vehicle, while the petrol engine provides electricity to power the motor.
An example of a series hybrid PHEV is the Chevrolet Volt, not to be confused with the Chevy Bolt, which is its purely-electric sibling.
2. Parallel Hybrids
Unlike series hybrids, these are propelled by the engine and the electric motor concurrently. The engines and electric motors of parallel PHEVs are connected to and can both turn the wheel.
Some parallel hybrids, under specific conditions, can occasionally switch to series when it is efficient. The electric-only propulsion mostly occurs at low driving speeds for parallel hybrids. The Honda Insight is an example of a parallel hybrid car.
3. Series-Parallel Hybrids
Series-parallel hybrids, as the name suggests, combine both characteristics and operate in either configuration.
The Toyota Prius is a perfect example of a series-parallel hybrid PHEV.
Pros and Cons of PHEVs
Pros
- Fuel efficient – PHEVs are characterised by economical petrol consumption (roughly 30% to 60% less) compared to conventional internal combustion engine vehicles.
- Low emitting – they also emit less gas, the volume of which depends on how electricity is generated.
Cons
- Expensive – plug-in hybrid vehicle units cost more than conventional hybrids and regular cars. However, the fuel cost for hybrids is much lower since electricity is cheaper than petrol.
- Recharging takes time – PHEVs take a long time to recharge from a 120-volt household outlet. A 240-volt house/public outlet recharging will take roughly 2 to 4 hours, while a fast-charger will take around 30-minutes.
You may refer to our other article to compare PHEVs with fully-electric vehicles, or bookmark our site for updates. If you wish to search for online auto parts stores, there’s no need to go far. You can do it here through our buy and sell platform or directory at Carpart.com.au!