Vehicle braking strategies based on regenerative braking boundaries of electric machines

Abstract

Electric and hybrid-electric vehicles are capable of providing electrical braking to assist mechanical brakes during a braking event. Braking strategies can be formulated to dictate the manner in which the braking effort is shared between the electrical and mechanical brakes. Electrical braking capability is identified by regions in the braking quadrants of an electric machine's torque-speed plane, and these capability regions may be further subdivided into regenerative and non-regenerative braking regions. Regenerative electrical braking adds energy to the energy storage system, whereas non-regenerative electrical braking subtracts energy from the energy storage system. This paper uses the concept of regenerative braking boundaries to define braking strategies that avoid operation in non-regenerative braking regions so as to recover as much electrical energy as possible during braking events.

Modelization and experimental validation of CHB inverters for EVs and efficiency comparison with IGBT and SiC inverters on realistic driving cycles

“…During slowdown phases, a braking strategy needs to choose a distribution between regenerative and dissipative brake according to the ED limits. various solutions are available, as described by [39], [40].…”

Comparison of Different Braking Strategies to Improve the Energy Recovery of an Electric Vehicle Based on Cascaded H-Bridge Inverter with Batteries

“…Then, the coupling element (3) is inverted by (7). It is used to distribute the total reference traction/braking force between the wheel force F wh ref and mechanical brake force F bk ref references, especially during the braking phase.…”

“…Increasing the energy density of batteries and improving the overall efficiency of the traction system are therefore sought. In this context, this paper follows two parallel axes of improvement: the use of an innovative battery subsystem based on a Cascaded H-Bridge inverter with Integrated Battery cells (CHB-IB) [4]- [6], and the development of an energy management strategy capable of increasing energy recovery during braking phases [7]- [10].…”

Fast charging systems for supercapacitors – circuit solutions and comparative study

“…The capacity of the supercapacitor C SC presents the equation (1), where u SC -the voltage on the supercapacitor clamps, C SC0 -the capacity of the supercapacitor at voltage 0 V, ak -the quotient describing the relation between the supercapacitor's voltage and capacity.…”

“…The problem especially includes hospitals, governmental entities and any other place or institution where power failure can pose a threat to the human life. Another necessity of energy storage relates to power recovery systems, e. g. braking in electrical vehicles, elevators and others [1]. In all of these cases and many others, manufacturers use various methods to keep the electrical energy stability.…”