The loader has a lot of recoverable braking energy due to its larger mass and frequent starts/stops. For a 5-ton pure electric drive loader, an emergency braking intention recognition strategy based on hydraulic braking pressure was proposed. The braking intention recognition strategy of an acceleration pedal and brake pedal was used to distinguish different braking intentions, and the hydraulic braking system pressure was used as a feedback parameter for emergency braking intention recognition to improve braking safety. Aiming at electro-hydraulic composite braking mode switching, a collaborative control strategy of walking regenerative braking and mechanical braking is proposed. Simulation analysis by AMESim and vehicle test results show that the proposed control strategy can realize driver braking intention recognition and electro-hydraulic braking force distribution under different working conditions and improve braking smoothness. According to the calculation of the energy recovery effect evaluation index, the energy recovery efficiency is up to 71.64%, the braking recovery rate is above 42.50%, and the maximum energy saving for the whole vehicle is 7.58% under one cycle condition. The proposed strategy has a good energy-saving effect.

As a widely-used construction machinery, the electric loader has the potential to recover braking energy due to its large mass and frequent starts and stops. Identifying braking intention accurately is the foundation of braking energy recovery. The typical braking condition of an electric loader is analyzed; the braking intention is divided into sliding brake, mild braking, moderate braking, and emergency braking. A large number of braking data were collected under different braking intentions, which are used as the basis for fuzzy control variable partitioning, fuzzy controller parameter setting and fuzzy control rule formulation. The control strategies of deceleration intention identification based on accelerator pedal, braking intention identification based on brake pedal and sliding brake intention identification are proposed in this paper, respectively. This paper takes the hydraulic brake pressure as a feedback parameter, even if there is hysteresis or failure based on the intention of pedal identification, the system can still provide sufficient braking strength to ensure the braking safety. The AMESim(R12)-Matlab/Simulink co-simulation model and prototype are built to verify the feasibility of the control strategy under different braking intention identification. The results show that the braking strength under stronger braking intention can satisfy the braking demand whether at a speed of 2 m/s or 12 m/s, which ensures the safety of emergency braking, and the electric loader can provide stable braking strength under different braking intention and different speed. This has good braking stability.

With the escalation of global warming and environmental pollution, electric products characterized by zero emissions, low vibration, and minimal pollution are increasingly favored by consumers. As a pivotal loading and transportation tool, the electrification of forklifts progressed earlier and is relatively mature. However, the prevalent low-voltage systems (72 V or 80 V) in current electric forklifts exhibit issues such as elevated heat loss, restricted motor instantaneous power due to voltage constraints, susceptibility to electrical erosion, and challenges in achieving rapid charging. To address these challenges, a powertrain solution employing high-voltage lithium batteries (320 V) as energy storage units for electric forklifts is proposed. The key parameters of the high-voltage lithium battery were meticulously calculated and selected. The powertrain architecture of the high-voltage lithium battery electric forklift was analyzed, and operational conditions were thoroughly examined. To verify the superior energy efficiency performance of the proposed high-voltage electric forklift in comparison to its low-voltage counterparts, a test prototype was constructed, and comprehensive tests, including average energy consumption and thermal equilibrium assessments, were conducted. The test results demonstrated that under average energy consumption conditions, the operational duration ranged from 8.89 to 13.34 h, surpassing the 7.5 h achieved by low-voltage electric forklifts. The thermal equilibrium temperatures of all electrical control units remained below 43 °C, significantly lower than the 80 °C shutdown protection threshold allowed for low-voltage forklifts. These findings indicate that the proposed high-voltage lithium battery electric forklift exhibits relatively low energy consumption, significantly enhances overall operational efficiency, and ensures stable operation, providing a viable solution and reference for the electrification of forklifts and other construction machinery.