Technology: What exactly is the iTAC that BYD has always talked about?

BYD has always used technology as a selling point for their products, such as their blade battery, e-platform 3.0, unibody and highly integrated electric drive system, etc.

Among many technical terms, there is one technology called iTAC, the full name is intelligence Torque Adaption Control, which is BYD's intelligent torque control system.

This system has been applied to BYD's current models, such as the BYD SEAL Performance AWD model, which is equipped with this technology. What exactly is this technology? What does it do?

Looking at this term alone, it's easy to think of Mazda's GVC system, the two have similarities, but there are more differences. Both systems control the output torque of the power system, and assign it accurately to a single side or even a single wheel. The difference is that the power source of GVC system is the internal combustion engine, while the power source of iTAC system is the synchronous motor. Besides, the purpose of GVC is to improve the handling performance of the vehicle in the curve, while iTAC is more focused on the safety of the vehicle control. Of course, iTAC can also improve the handling performance of the vehicle.

In a word, the iTAC system, based on the extremely fast response speed of the motor, can adjust the output torque of each motor in real time, minimize the changes in the vehicle's power, and improve the safety, comfort and handling of the vehicle.

Generally speaking, to maintain vehicle stability requires to monitor the vehicle's operating status in real time. The past methods usually rely on wheel speed sensors, which monitor changes in wheel speed. If the speed of one side of the wheel rises sharply, it is likely to have skidded, and the braking system begins to intervene. However, the wheel speed sensor divides each round of the wheel end into only 32 or 48 collection positions, and the accuracy of information collection is low, which can't meet the requirements of electric vehicles.

iTAC technology can significantly improve the speed and precision of data collection. Through the use of the motor rotation sensor, each rotation of the wheel can be divided into 4096 collection points. In terms of response speed, the recognition accuracy of iTAC is improved more than 300 times, and can predict wheel speed changes more than 50ms in advance. In case of abnormal grip at the wheel end before slipping, the system can recognize the abnormal grip in advance and adjust it, allowing the vehicle to regain stability.

On the control strategy, traditional control strategies can only control the vehicle by reducing the torque through braking when facing slip. However, iTAC, based on its advanced prediction, provides multiple methods such as transferring torque, properly reducing torque, and outputting negative torque for the characteristics of quick motor response speed and more precise speed adjustment.

BYD has previously carried out a series of tests on the iTAC system. According to the official low adhesion surface test results, in the 0-60km/h snow straight line acceleration, iTAC allows the vehicle to avoid starting slippage, and the acceleration time is 0.7 seconds faster than that of vehicles without iTAC functions. When starting on ice-asphalt docking surface, iTAC technology significantly suppresses wheel slippage, leading to the vehicle quickly drive off the ice. In the snow step-response test, iTAC keeps the vehicle in a stable driving state with the vehicle sliding in a stable linear form. In the circular snow test, iTAC technology allows the vehicle to maintain a drift state, without too much steering correction, and at the same time increases the speed by 5-10km/h.

This difference under the low adhesion road surface is also equally applicable to wet and slippery surfaces. It is clear that the iTAC system can enhance the stability of the vehicle by precisely adjusting the torque output, thus achieving the aim of improving safety and control.