A new three-phase optimal-harmonic-power-flow (TOHPF) method is propos
ed. It is designed to minimise the three-phase power losses and the to
tal three-phase harmonic voltage distortion while satisfying the three
-phase-power-flow equations, three-phase harmonic-power-flow equations
, three-phase security constraints, and the three-phase harmonic stand
ard etc. A two-level algorithm is used to solve the problem: the maste
r level determines the settings of three-phase compensators and taps;
the slave level includes subproblems which involve cases of fundamenta
l and harmonic frequencies separately. The test results for two power
systems show the applicability of the proposed method.