Field-Oriented Driving/Braking Control for Electric Vehicles

Abstract

Most electric vehicles use regenerative brakes, since this kind of braking system design recycles electromotive force to increase electric power endurance during braking. This research proposes a sensor-free, integrated driving and braking control system that uses a space-vector-pulse-width module to synthesize stator current by purpose. It calculates the rotor position angle of the motor by detecting variation in the stator current and completes a closed-loop control. When the motor receives a brake command, the controller changes the inverter-switching sequence to generate reverse torque and a magnetic field to complete the driving or braking function using field-oriented control (FOC). This provides a smoother and more accurate motor control than sinusoidal commands with Hall feedback. Compared to the regenerative brake and rheostatic brake, the proposed braking system has a powerful braking torque and shorter reaction time. Comparisons of reaction times for a modified four-wheel electric vehicle equipped with a permanent magnet synchronous motor under neutral-sliding-status, FOC based braking, and short-circuit braking were conducted.

A comparative braking scheme in auto-electric drive systems with permanent magnet synchronous machine

“…The maximum regenerative power point torque (MRPP-Torque) equations for the SMPM and IPMSM are obtained by substituting in ( 5) and ( 12) into ( 14) and (15) which gives rise to (16) and (17).…”

“…In [14], a combined three torque control methods in regenerative braking design was elaborated. Some published research works have dwelt on the system braking design of electric motors based on shortcircuit braking which converts motor back-EMF directly to braking torque [15], [16]. Though this technology is applied to electric bicycles and motorcycles, its speed limitation and losses makes it very inefficient.…”

Field Oriented Control untuk Pengaturan Kecepatan Motor BLDC pada Sepeda Motor Listrik

“…Adanya offset fasa dari torsi dan input daya yang diberikan akan menyebabkan efisiensi menjadi buruk. Untuk dapat mengatasi masalah ini maka kontroller FOC diperlukan untuk mengatur pembangkitan torsi yang sebanding dengan sinus dengan mengatur logika kontrol pada sudut pergantian menjadi 90 o sehingga torsi yang dihasilkan dari motor BLDC menjadi maksimal [14][15][16][17]. Keunggulan kontroller FOC dapat mengurangi getaran yang dihasilkan oleh motor yang disebabkan oleh penggunaan PWM switching, selain itu dengan menggunakan kontroller FOC, konsumsi daya yang diserap oleh motor menjadi efisien [18].…”

Sensorless Control of PMSM Based on Backstepping-PSO-Type Controller and ESO-Type Observer Using Real-Time Hardware

“…The FOC-type control strategy of the PMSM includes all the advantages deriving from the simplicity of using PI controllers, but inherently, the control performance is limited due to the non-linear PMSM model, the need to perform the control in a wide range and with a high-dynamic of speed and load torque, but also due to the parametric uncertainties resulting, in particular, from the variation of the combined rotor-load moment of inertia [6,7].…”