Research On The Energy Storage Unit And Its Management System Of Hybrid Excavator

For the special working condition of hybrid hydraulic excavator, some special requirements were proposed for its energy storage device and management system, In this paper, the energy storage device and its management system centralized on the hybrid hydraulic excavator was researched, the major progress is as follows:1. According to analysis of excavator working condition and comparison of various energy storage unit, I selected the impetus NIMH battery as a energy storage unit for 5t parallel hybrid hydraulic excavator, then chose the parameter of NIMH battery through the requirements of voltage, power, energy, and life.2. Through a comprehensively experimental platform which built by our team, I carried out some tests and analysis of NIMH battery packs on the basic character of battery, then on this basis, established of an improved RC equivalent circuit model of battery..3. For fluctuating current conditions of battery in HHE , this paper presents a new SOC estimation model through the combination of improved RC model and the energy conservation SOC estimation model, which observed through sigma-point kalman filtering precisely, the model can be combination of the two priority points, and adapt well to the excavator's multi-working-model and load characteristics. Besides, Researched the battery's SOH estimation methods preliminarily, and established its estimation methods and steps.4. Designed the hardware circuitry and embedded software system of the battery management system based on the DSP chip TMSLF2812, mainly including equalizing control circuit for battery packs, charging current control circuit, electrical control board and software system on DSP / BIOS.