ANALYSIS AND DESIGN OF A COMBINED SYSTEM OF SHUNT PASSIVE AND ACTIVE-FILTERS

Passive and active filters have traditionally been used to reduce harmonics in power systems. Only recently combined systems of shunt passive and active filters have been proposed in order to overcome the technical problems of passive filters and to reduce the costs of active ones. The paper tries to overcome some drawbacks of a combined filtering system (modified high-pass filter) which appeared in literature. In particular, improvements in the system structure and in the steady-state design methodology are proposed to obtain a filtering system with both satisfactory compensation characteristics and low costs. Finally, numerical applications are discussed considering a test case.