A Time-Domain Harmonic Power-Flow Algorithm for Obtaining Nonsinusoidal Steady-State Solutions

Steady-state simulation plays a vital role in power system analysis and design. Over the past 25 plus years, various steady-state methods have been proposed. Most of these methods only deal with how to obtain steady-state waveforms of a system in an efficient manner. Only a few of them also take power-flow constraints into account. The majority of these “power-flow” methods are implemented in the frequency domain, which inevitably suffers from harmonic truncation errors. Moreover, the problem of model incompatibility will rise when they are used for the steady-state initialization of a time-domain electromagnetic transient (EMT) program. This paper presents a harmonic power-flow method, which is implemented entirely in the time domain. The proposed method essentially extends a time-domain steady-state method, called “shooting method” to include the power-flow constraints and to account for aggregate loads in the power-flow calculations.