Simultaneous Identification and Control Using Active Signal Injection for Series Hybrid Electric Vehicles Based on Dynamic Programming

Abstract

Hybrid electric vehicles (HEVs) have an over-actuated system by including two power sources, a battery pack and an internal combustion engine. This feature of HEV is exploited in this paper to simultaneously achieve accurate identification of battery parameters/states. By actively injecting current signals, state of charge, state of health, and other battery parameters can be estimated in a specific sequence to improve the identification performance when compared to the case where all parameters and states are estimated concurrently using the baseline current signals. A dynamic programming strategy is developed to provide the benchmark results about how to balance the conflicting objectives corresponding to identification and system efficiency. The tradeoff between different objectives is presented to optimize the current profile so that the richness of signal can be ensured and the fuel economy can be optimized. In addition, simulation results show that the Root-Mean-Square error of the estimation can be decreased by up to 100% at a cost of less than 2% increase in fuel consumption.With the proposed simultaneous identification and control algorithm, the parameters/states of the battery can be monitored to ensure safe and efficient application of the battery for HEVs. NomenclatureLinearized OCV-SOC slope (V) Frontal area of the HEV (m 2 ) Constants of linearized OCV-SOC curve (V)

An Overview of Modelling and Energy Management Strategies for Hybrid Electric Vehicles

“…Power distribution is achieved through ADHDP by enumerating the design shift commands. In [156], Zhu et al provided benchmark results on how to balance conflicting objectives corresponding to identification and system efficiency through the DP strategy. This method monitored battery parameters and identified vehicle status to ensure battery safety and efficient operation of the HEV.…”

Economic Payback Time of Battery Pack Replacement for Hybrid and Plug-In Hybrid Electric Vehicles

“…For both ICE and EMs, maximum and minimum allowed torque values are retained as a function of the angular speed of the corresponding component in ( 9) to (11). In (9), the ICE can deliver positive torque only, while in (10) and in (11) the torques of the EMs can have negative values as well when generating electrical power. In (12), 𝐼𝐶𝐸 𝑜𝑛/𝑜𝑓𝑓 is a binary variable for the ICE state, and values of 0 and 1 relate to the ICE being off and on, respectively.…”

“…Moreover, vehicle batteries enable storing electrical energy harvested in regenerative braking for future use as propelling energy [7]. It is therefore crucial that the battery operates effectively throughout the entire HEV lifetime, even as the battery ages significantly [8] [9].…”