Comparing ST ATCOM Direct and Indirect Control Algorithms: A Laboratory Investigation

In contrast to the Direct Current Control (DCC) method, which uses converter and load currents to control reactive and harmonic components, the Indirect Current Control (ICC) methodology employed by STATCOMs works differently. The ICC method adjusts the source current to remove the quadrature current component rather than directly measuring the load current and converter current. This method eliminates the need to directly measure the load or converter current by modifying the source current to cancel out the reactive component. The STATCOM can control the non-linear load's reactive and harmonic current needs by drawing the active current component from the source current. Both methods improve power system reliability by compensating loads adequately. Promising results have been obtained from experimental testing that compared DCC and ICC strategies utilizing the Imperix rapid prototyping platform. The study demonstrates the effectiveness of these control strategies in the laboratory environment.