What does TDD stand for according to IEEE 1159?

Total Demand Distortion, abbreviated as TDD, refers to a specific metric for assessing the quality of electrical systems, particularly in relation to the harmonic content of power signals. This measurement takes into account the total demand of non-linear loads that contribute to harmonics in the system. By evaluating the Total Demand Distortion, engineers can determine the extent to which harmonics affect the overall performance of the electrical system, helping identify potential issues like overheating or equipment malfunction. Understanding TDD is vital for compliance with industry standards and ensuring reliable and efficient operation of electrical installations.