Traditional construction machinery uses diesel as the main energy source, which emits high emissions, pollutes the environment, has low energy utilization, and seriously wastes resources; in February 2019, the Ministry of Ecology and Environment issued a draft for comments that clearly stated: "Since December 1, 2020 Since the beginning, non-road mobile machinery that does not meet the requirements of the fourth stage of "GB20891-2014" cannot be produced, imported, or sold".
Loaders are widely used in construction sites, mines, ports, highways and other construction fields. Frequent start and stop (mainly loading and unloading and short-distance transportation) are required during the operation process. The energy consumption is high, the noise is large, and the pollution is serious. The market needs to meet the operational performance Under the premise of providing a more environmentally friendly, energy-saving and efficient power system. Busy at both ends, telescopic loaders, underground loaders
【Principle of Power System of Pure Electric Loader】
The loader power system has two series of products, pure electric and tandem hybrid. The pure electric and series hybrid system schemes have the same driving part, using electric motor + 2-speed AMT gearbox as the power output to drive the entire vehicle; the difference is that the pure electric power battery needs to be externally charged, and the hybrid power uses "engine + power generation". The machine’s extended range system" recharges the power battery. This article takes Green Control's pure electric wheel loader power system as an example for analysis.
1. Product parameters
2. Working principle
Common working modes of loaders: t0 forward without load-t1 shovel loading materials-t2 reverse transportation-t3 steering/forward/discharging materials-t4 backward without load-t5 forward without load. During the operation, the whole machine is in a state of frequent shifting, coupled with various unexpected conditions during shoveling, making the power output of the loader and load fluctuations very complicated.
In the driving and operation of pure electric loader, the energy comes from the on-board power battery, and the power is output through the electric motor.
【Advantages of pure electric loader system】
1. High efficiency and energy saving
The engine of a traditional loader has a low overall working efficiency, and the average efficiency of the hydraulic torque converter is less than 70%. The braking energy of the whole machine cannot be recovered, resulting in high fuel consumption and poor emissions. The high efficiency of the electric motor of the pure electric system exceeds 95%, the average efficiency of the gearbox can reach 97%, and the braking energy recovery is increased.
2. Strong power
The 5T ground loader equipped with a pure electric system has a large gradeability of 30%-58% and a high speed of more than 40km/h; the output can exceed 175KN and the large traction force exceeds 160KN, which is 10% higher than the traditional fuel engine .
3. Clean and environmentally friendly
Loaders equipped with pure electric systems have zero exhaust emissions, and the noise is as low as 70-80 decibels, which is 20-30 decibels lower than traditional loaders.
4. Higher returns
Pure electric loaders can save more than 130,000 yuan in fuel per year compared to traditional vehicles. The longer the average daily use time, the higher the operating profit. In addition, the pure electric system has a simple structure, low maintenance requirements, and less impact on production operations; this will greatly save maintenance time, material and labor costs (for example, the life of brake pads can be more than doubled).
Pure electric loaders, due to the limitations of the development of the new energy industry, are currently more suitable for working conditions or zero-emission demonstration areas where charging is convenient and a single continuous operation time is short. The advantages of the product are no emissions, energy saving and money saving, simple and compact structure, and low use cost; the disadvantage is that the purchase cost is high, and it needs to be charged frequently (sustainable work, depending on the battery capacity).
With the advancement of science and technology, the gradual improvement of battery and motor systems, applied to future pure electric loaders, will bring users a higher value of operational quality.