An ECMS-based powertrain control of a parallel hybrid electric forklift

Abstract

In this paper we focus on the supervisory control problem of a parallel hybrid electric vehicle (HEV): minimize fuel consumption while ensuring self-sustaining State-of-Charge (SoC). We reapply the state of the art methodology by comparing optimal results of Dynamic Programming (DP) against a realtime control candidate. After careful selection, we opted for an Equivalent Consumption Minimization Strategy (ECMS) based approach for the following reasons: (i) results are quite remarkable with less than 5% fuel usage increase when compared to DP; (ii) simple and intuitive tuning of control parameters; (iii) readily usable for code generation (prototyping).Topics that distinguish this article from others in the literature include: (i) the usage of trapezoidal rule of integration implementing DP and ECMS; consequently, the offline simulation results are intended to be more precise and representative when compared against the more common, often used rectangular rule; (ii) a particular post-processing procedure of the recorded driving cycle data based on physical interpretation; it allows consistent offline simulations with quite high sampling period (in the order of seconds); (iii) tuning of control parameters in such a way that control system is robust towards new, unknown, unpredictable but closely resembling driving cycles.In particular, we focus on the supervisory control of a forklift truck. The real-time control is able to compute: (i) the power split (i.e. a balanced usage between an internal combustion engine and a supercapacitor); (ii) the drivetrain control (i.e. automatic gear shifting and clutching). Numerous numerical implementation issues are discussed along our presentation.

An Optimal Fuzzy Logic-Based Energy Management Strategy for a Fuel Cell/Battery Hybrid Power Unmanned Aerial Vehicle

“…The simulation and HIL experimental results verify the proposed EMS strategies. Some online EMS algorithms, such as MPC [35][36][37] and equivalent-consumptionminimum (ECM) [41,42], have been used to manage the HEPS, but these methods are only based on the limited time horizon length, and the solutions give the sub-optimal result for EMS. Since the myopic optimal strategy such as MPC only involves the information on the current or limited time step state for UAV, it cannot provide a global optimal policy for EMS of UAVs.…”

“…The optimal solution will be tracked through collaboration and information sharing among individuals in the population such as flocks of birds or schools of fish. These features provide the possibility to adjust the thresholds of membership functions in fuzzy logic control in optimization form [41].…”

AssistMe: Policy iteration for the longitudinal control of a non-holonomic vehicle

“…industrial controllers or single-board computers). For this reason, SDP is particular appealing to the automotive sector [16].…”

“…However, our contribution differs with respect to the following points: (i) the application is different (a power wheelchair, not a passenger car); (ii) the optimization is carried out in terms of total time to complete the task (obstacle avoidance), not energy (e.g. minimize fuel consumption versus battery usage in hybrid electric vehicles [23,24,22,16]); (iii) the framework is different (control of semi-autonomous vehicles, not autonomous vehicles); (iv) the stochastic model is different (user intention, not the driving cycle); (v) environment awareness is ensured online via time-of-flight sensors able to detect obstacles, whereas other means are necessary to identify (classify) driving cycles.…”

Hybrid battery–supercapacitor system for full electric forklifts

“…A higher level of efficiency can be mainly reached by the optimisation of the forklift routing, the adoption of storage policies that allow us to minimise the number of movements for material handling; the adoption of forklift characterised by lower energy consumption [29, 30]. In this sense, different forklifts have been developed, in [31, 32], triple‐hybrid systems including a fuel cell, battery and super‐capacitor were investigated for a forklift system; system power management strategies were studied, i.e. the battery state of charge (SoC) control and the battery (DC bus) voltage control.…”