Real-time optimization of an active filter´s performance

Recent advances in power electronics have meant that many loads now draw a distorted current from the power supply. For the same real power consumed, the apparent power for the distorted load is greater than the equivalent sinusoidal load. A real-time active filter optimization algorithm has been implemented in a TMS320C30 DSP, with the aim of maximizing the monetary saving from active filtering by reducing the apparent power consumed at the point of supply. As the basis for this optimization a savings function which takes into account active filter efficiency, the cost of energy, and the supply and load current distortion before and after filtering, has been derived. A simplex optimization technique, which is able to find the optimum operating point even under varying load conditions, is used to maximize these energy savings