用于电能质量预测分析的交流电弧炉时变参数模型

Time-varying Parameter Model of AC Electrical Arc Furnace for Power Quality Predictions and Analysis

基于能量守恒定律建立了一种以微分方程描述的交流电弧炉(EAF)时域模型,模型以电弧导纳作为状态变量,电弧电流和弧长作为输入,进一步根据弧长与电弧电压关系式推导出模型参数与弧长的关系,并给出时变参数的工程估算方法。以实际炼钢交流电弧炉为例,将带通白噪声信号叠加在弧长上模拟实际工况,分别对熔化期和精炼期电弧炉的动态特性以及电网的电压波动和谐波进行仿真研究,仿真结果与实测数据相吻合,证明了模型的有效性和实用性。

A novel time domain differential model is proposed for the AC EAF（Electrical Arc Furnace） based on the law of conservation of energy. The model is established with arc admittance as a state variable, and with arc current and arc length as the input. The relation between the parameters with arc length is derived from the formula of the arc length and voltage. The engineering estimation method of time-varying parameters are further realized. Moreover, the limited bandwidth random signal is added on the arc length, and actual working state was simulated. A real EAF is taken to simulate the dynamic characteristics as well as the grid voltage fluctuation and harmonic wave in melting and refining stages. The results coincide with the measured data so prove the validity and practicability of the model.