Development of the smart annealing unit and analysis of low-frequency conducted disturbances by connection to low voltage public network

Abstract

Within the research activities, the realization team did the complete development of the annealing unit with the aid of modern technology and components, such as the programmable logic controller, industrial PC, and microcontrollers, to secure an intelligent way of switching the power semiconductor switches (SSR relays) with regard to minimizing the low frequency conducted disturbances. The annealing unit has the implemented algorithm for two ways of output power control, i.e. phase control and full wave control. The algorithm of the full wave control is designed in a way so as to arrange the balanced power in the load. By using this way of control, the harmonic emission is almost entirely eliminated, but the influence of the flicker effect will surface.

The article offers a complex view at the annealing unit from the control method perspective, ensuring the correct annealing cycle and subsequent influence of the annealing unit to supply network. It deals deeply with EMC analysis for both ways of designed annealing unit control. The analysis comes out from the experimental measurements on the functional annealing unit prototype.