In many fields of science and engineering. partial differential equation (PDE) constrained optimal control problems are widely used. We mainly solve the optimization problem constrained by the time-periodic eddy current equation in this paper. We propose the three-block splitting (TBS) iterative method and proved that it is unconditionally convergent. https://parisnaturalfoodes.shop/product-category/org-no-salt-vegetable-bouillon-cubes/