Common Application Platform for Low Voltage Network Management

在本提案中，将进行实验室测试和热建模，以完善和验证低压（LV）配电变压器的动态热额定（DTR）算法，以应对未来由分散代，电动汽车，在制造过程中，将在变压器绕组中嵌入多个光纤传感器，制造专用11kV/0.433kV三相配电变压器。这个变压器将作为实验室的测试对象。变压器的热额定和寿命评估取决于变压器内部的热点温度。由于暴露在最大泄漏场和周围高油温中，通常假设热点位置靠近绕组的顶部位置，但以往的经验表明，情况并非一定如此，热点位置可能位于较低的导体位置。因此，将在每个绕组的顶部区域安装多个传感器以捕获热点温度。此外，还将监测变压器内的顶油和底油温度。行业用于确定变压器健康状况的额外状态监测措施，例如在线溶解气体分析监视器（已在实验室中提供）将在测试期间应用，以提供补充信息。升温试验将分两个阶段进行。首先，将在多个等级的恒定负荷下进行长时间热运行测试，例如额定负荷的70%、100%和120%。IEC热模型中用于计算最热点温度所需的热参数可以根据热运行测试结果进行细化。其次，将负荷分析和预测算法得到的一系列动态负荷曲线应用于热运行试验，验证热模型及其参数。所提出的配电变压器DTR算法能够应对低压电网中未来可预测和不可预测的负荷情况。

In this proposal, both laboratory testing and thermal modelling will be carried out to refine and validate the dynamic thermalrating (DTR) algorithm for low voltage (LV) distribution transformers in order to cope with future dynamic loading scenarioscaused by dispersed generations, electric vehicles, heat pumps and etc.A specially commissioned 11kV/0.433kV three phase distribution transformer will be manufactured with multiple opticalfibre sensors embedded in the transformer winding during the manufacturing process. This transformer will be used as thetesting object in the laboratory. Thermal rating and life assessment of a transformer are dependent on the hotspottemperature inside the transformer. While the hotspot location is usually assumed to be near to the top position of thewinding, due to the exposure to the maximum leakage field and the high surrounding oil temperature, previous experiencehas shown that this is not necessarily the case and it could be located at lower conductor positions. Therefore multiplesensors will be installed at the top region of each winding to capture the hotspot temperature. In addition, top oil and bottomoil temperatures inside the transformer will be monitored. Extra condition monitoring measures used by the industry todetermine the health condition of transformers, e.g. on-line Dissolved Gas Analysis Monitor (already available in thelaboratory) will be applied during the tests to provide complementary information.The temperature rise tests will be implemented in two stages. First, prolonged heat run tests will be conducted undermultiple levels of constant loadings, such as 70%, 100% and 120% of rated loadings. The thermal parameters required inthe IEC thermal model for calculating the hottest spot temperature, can be refined based on the heat run test results.Second, a series of dynamic load profiles obtained from the load analysis and forecast algorithm will be applied in the heatrun tests to verify the thermal model and its parameters. The developed DTR algorithm of distribution transformers wouldbe able to cope with future predictable and un-predictable loading scenarios in LV networks.