Reduce EV range anxiety and improve safety using integrated FOC motor control and advanced sensors
The cost, safety, and range anxiety issues facing EVs The issues that designers of xEVs must address are many, including vehicle cost, safety and reliability—particularly so in light of the increasing levels of vehicle autonomy, driving range per charge (range anxiety), and battery pack lifetime. To support safety and reliability, advanced sensors are needed that meet the requirements of advanced driver assistance systems (ADAS) functions as defined in ISO 26262. For cost and range, designers have turned to higher voltage power rails of up to 800 volts for greater efficiency and reduced cable weight, while also taking advantage of improvements in battery pack design. For example, better battery thermal management has contributed to greater driving range and longer battery life, while improved cooling for EV and HEV traction inverters helps to increase power and energy densities and reduce weight. While higher levels of semiconductor device integration are enabling greater functionality with less weight and space, the BLDC motors required for the requisite cooling fans must be
Designers of electric vehicle (EV) and hybrid electric vehicle (HEV) (often referred to as xEV) systems are under constant pressure to deliver more miles per charge to reduce range anxiety and lower vehicle carbon footprints. At the same time, they need to add more motors, sensors, associated electronics, processors, and software to meet higher levels of vehicle autonomy, user features, and safety, while also driving down costs. Motors for doors, windows, battery cooling fans, radiator fans and pumps, and other features are a particularly thorny issue as not
by the need to also meet ISO 26262 functional safety requirements and AEC-Q100 quality standards. To meet these challenges, designers can turn to a variety of automotive qualified devices that provide higher levels of hardware and software that simplify the design and integration of various functions, while also reducing parts counts and overall footprint. This article discusses the issues facing designers of EVs and HEVs. It then introduces and shows how to use a highly integrated FOC brushless direct current (BLDC) motor controller and an associated evaluation board to kickstart an efficient EV/HEV motor design. It also presents various sensors to monitor current, 3D position, speed, and direction, all from a single source, Allegro MicroSystems .
By Jeff Shepard Contributed By DigiKey's North American Editors
only do they add weight, they also require advanced control
algorithms such as field-oriented control (FOC) to minimize noise and power consumption, while ensuring a smooth response. The overall system design task is complicated
we get technical
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