Design and Control of a Novel hybrid Active Power Filter based on Load Harmonic Currents Separation with the aim of DC-link voltage minimization in voltage source converter

This paper proposes a new hybrid active power filter, including voltage source converter (VSC) based active power filter and Thyristor Controllable LC Passive Filter (TCLC-HAPF) for eliminating harmonic load current components and compensating reactive power. This new structure which is based on the separation of high and low-frequency components of load current idea can reduce the drawbacks of both active and TCLC based filters. Low-frequency components of the load current applied to the active power filter and high orders are applied to the controllable thyristor passive filter (TCLC). The DC voltage minimization strategy which is based on DC voltage calculation in the fundamental and harmonic frequencies has been used for reducing the power losses and overall cost. The proposed structure is not only able to keep the network power factor more than 0.9 but also maintain the network current THD at %4.8 under the worst case of the load operation, which both satisfy the IEEE519-2014 standard. Also, the operation of the proposed hybrid filter at a minimum DC voltage reduces switching losses. This strategy has less computational burden compares to the traditional methods. The proposed idea reduces the THD of network current and satisfy the IEEE519-2014 standard and also enhance the power factor. To validate the operation of the proposed Hybrid Active Power Filter a part of the sample power network has been simulated and studied by using PSCAD / EMTDC software.