“Toyota bZ4X/Subaru Solterra: Equipped with various electrification products from Denso2022/4/13 (Wed) 14:00
Current Sensor
Toyota bZ4X (left)/Subaru Soltera (right)ESU (Electricity Supply Unit)High-efficiency eco heat pump system radiation heater
DENSO has developed products that contribute to improving the utility of electric vehicles (EVs) by extending cruising range, shortening charging time, and extending battery life. Each product will be used in the Toyota bZ4X, scheduled for release on May 12, and the Subaru Solterra, scheduled for release in mid-2022.
The newly developed electrification products include a current sensor that detects electric current, an ESU (Electricity Supply Unit) that integrates charging, power conversion, and power distribution functions, a high-efficiency eco heat pump system that uses heat from the atmosphere as a heat source for air conditioning, and a radiant heater that warms occupants’ knees. Other features include sensors that detect battery temperature and voltage, a battery monitoring ECU that monitors battery status, and a BEV ECU that aggregates information and controls energy, as well as the company’s inverter in the new BluE Nexus eAxle.
EVs without internal combustion engines have batteries as their only source of energy. Minimizing the energy required and efficiently recovering and using up the energy will lead to improved practicality. Aiming for efficient energy management throughout the entire vehicle, DENSO is developing technologies from the perspective of monitoring vehicle conditions and efficiently controlling and utilizing energy.
In order to maximize energy utilization, it is important to have an accurate and detailed understanding of the vehicle’s condition. bZ4X and Solterra use a new current sensor that detects the battery charge and discharge current, and an ESU that performs charging, power conversion, and power distribution functions. Vehicle information obtained through these products will be used for efficient energy control.
Current Sensor
By renewing the IC used in the previous product and adopting a coreless type that detects current without using a magnetic core, which would increase the product volume, the new product can handle high currents in the ±1200A range required for electric vehicles, while also achieving a 40% reduction in product volume. In addition, the adoption of the magnetic equilibrium type, which is less susceptible to the effects of magnetization, a factor that can cause measurement errors, has improved the current detection accuracy.
ESU (Electricity Supply Unit)
A group of products indispensable for electric vehicles, such as the integrated charging ECU that controls battery charging and Toyota Industries Corporation’s AC chargers and DCDC converters, are integrated into a single unit. The smaller size and lighter weight of the vehicle increases the capacity of the battery that can be installed, contributing to an extended cruising range and increased living space. The ability to quickly recharge the battery also contributes to shorter recharging times.
Efficient control and utilization of energy is the key to improving the practicality of EVs. bZ4X and Solterra adopt a new high-efficiency eco heat pump system that efficiently draws heat from the atmosphere and utilizes it for heating with less electricity. The bZ4X also features a radiant heater to warm occupants’ knees.
High-efficiency Eco-Heat Pump System
Realized the world’s first in-transit defrosting function. By defrosting using waste heat from driving and heating, it significantly improves electric cost performance under winter frost conditions. In addition, the precise cycle control and heat dissipation adjustment function utilizing a multi-function valve (MCV-e) have succeeded in making the refrigeration cycle a receiver cycle with a simplified configuration. Compared to the accumulator cycle used in general heat pump systems, this system improves cooling performance and significantly reduces the number of parts in the refrigeration cycle.
A multi-function valve (MCV-e) that controls the cooling water enables thermal coordination of the “”high temperature water circuit,”” “”low temperature water circuit,”” and “”refrigeration cycle. Simplifying the system by integrating the functions of each water circuit ensures quality and improves scalability to meet diverse needs. High-performance compact chiller improves battery cooling performance and contributes to longer battery life. It also maintains energy output by suppressing sudden temperature rises of the batteries, and enables efficient energy use-up even in environments where battery temperature changes significantly, such as during high-speed driving.
Radiant heater
Radiant heat from the heater surface efficiently warms only the occupants, and when used in combination with a heat pump system, reduces the air conditioning energy for the entire vehicle, contributing to an extended cruising range when the heater is used. The heater surface uses a thin film structure that warms up to more than 100 degrees Celsius in about one minute, quickly warming the occupant’s knees for comfort, and the world’s first heater structure and control technology that instantly lowers the surface temperature to below 50 degrees Celsius when the human body comes in contact with the heater surface for safety. A sensor that detects human contact and stops heating is also built into the film to ensure safety even when occupants remain in contact with the heater surface for long periods of time.”
