HYBRID SYNERGY DRIVE Core Technology Development Story
Tireless pursuit and practice
[HYBRID SYNERGY DRIVE System]
"Once a system, including the production facility, is established, it takes a great deal of effort to change its shape. This is because making a shift away from what already exists may entail starting from scratch. Is it possible to retain the basic system developed for the 1st generation Prius and still attain the targeted performance? Can we really deliver both outstanding fuel efficiency and powerful performance? Can we reduce costs? Developing the HYBRID SYNERGY DRIVE was just a series of headaches, one after another."
Development Staff
[High Output Electric Motor]
"In some cases, it is better to let a specialist manufacturer develop electric motors and generators. But, when it comes to developing an electric motor specifically to propel an automobile, especially one having a structural design to be integrated with the transmission system, we needed to develop something in-house."
Development Staff
[Prius engine - 1NZ-FXE]
"Let's say that the test results showed that the fuel consumption is poor. If it were a gas/petrol engine powered car, we can usually figure out what to do from years of experience. But, in the case of an gas/petrol engine for a hybrid vehicle, we had no clue as to what to do because it is intricately combined with the electric motor, battery and other components. This meant that any verification had to be conducted by running the prototype, verifying one item at a time. We had to learn a lot about electric motors and batteries, which are usually not directly related to gas/petrol engine."
Development Staff
[Highlander Hybrid engine - 3MZ-FE]
"We modified the base engine to match the system characteristics of the HYBRID SYNERGY DRIVE. We succeeded in improving the fuel consumption without sacrificing power in the end. The improvements we made to the various engine management systems have also resulted in clearing the most stringent emissions regulation in each country around the world."
Development Staff
[Power Control Unit/Inverter]
"We improved every aspect, the chip, heat sink material, circuitry and others, to develop an inverter that can work together with the gas/petrol engine. This was perhaps the key factor that allowed us to deliver the world's first hybrid vehicle that is kind to the environment."
Development Staff
[Power Control Unit/Voltage-Boosting Converter]
"We implemented a Voltage-Boosting Converter in the Power Control Unit, which steps up the voltage supplied from the battery in accordance with the acceleration of the vehicle. It is a small device, but it has contributed significantly in down sizing the electric motor and battery, as well as cutting down on the cost. It is an idea that matches handsomely with our hybrid vehicle."
Development Staff
[Nickel Metal Hydride Battery]
"Determining the physical properties of the battery, to accurately assessing the discharge status and control it within the intermediate range that will neither over-charge or over-drain the battery, were extremely difficult to achieve. It takes a very delicate and fine balance, like keeping a tennis ball in the centre of a racket face while you walk. Enhancing the battery performance, down sizing the battery and cutting the cost will be critical for hybrid vehicles to become more popular in the future. We will not be content with the status of things as they stand today. We will continuously pursue further technological advancements."
Development Staff
[Camry Hybrid Battery]
"A high-efficiency, low noise sirocco fan uses air inside the vehicle to cool the battery pack. With a larger fan diameter than conventional fans, and because fan noise and motor operation can be suppressed by operating the fan at low rotation, both interior quietness and battery cooling performance have been enhanced."
Development Staff
[Camry Hybrid Electric Motor]
"Unlike engines that are only capable of generating maximum torque at high RPMs, the hybrid vehicle power unit is capable of generating maximum torque instantly."
Kenichiro Fuse, Chief Engineer
[Camry Hybrid Engine - 2AZ-FXE]
"The engine is substantially upgraded, with a redesign that employs optimized intake and exhaust systems, as well reduced internal friction and enhanced engine-block/crankcase rigidity. The result is improved power output with exceptional fuel economy and reduced noise and vibration levels."
Development Staff