Applications of tuned passive harmonic filters in a busbar with non-linear loads

Conservative Power Theory (CPT): A New Approach to the Tuned Passive Filter Design

“…This is due to the insertion of the capacitor of the filter that acts as a capacitor bank for correction of power factor for fundamental frequency, below the tuning point and therefore, observing the equation (16), we can notice the decrease of the reactivity factor, dependent on the reactive power Q, which has been corrected by this compensation. Another point to emphasize is the large decrease in the residual power D and, consequently, the nonlinearity factor D  , this can be better explained by observing equations (10) and (12), which show that D is proportional to residual current, that is, this indicator strongly depends on the presence of non-linearity between the voltage and current waves. Thus, with the filtering of the 5th harmonic current through the filter, the residual current decreases.…”

“…It is known that the effective values of voltage and current directly influence the power of the supply source, this power is characterized by the product of the effective values of voltage and current. Defined as apparent power, it can be decomposed into expressions (12) and (13).…”

“…That is, at the fundamental frequency, 60 Hz, will always be below the tuning frequency of the filter, so the filters behave as reactive compensators, or as commonly called, capacitor bank for power factor correction. In addition, because they have a simple construction, in comparison with the other techniques, they have low costs of construction and maintenance [12]. Using the three composite passive elements in a series circuit, we have the following input impedance:…”

“…The frequency ω 0 is a characteristic of the RLC circuit because it depends only on the components L and C. This characteristic can be seen in Figure 1, in which the impedance module and the phase of the RLC circuit, respectively, are represented for a filter tuned, that is, a single-tuned resonant filter for only one frequency [12]. When observing Figure 1, it is noticed that the impedance at the resonance frequency is minimal, demonstrating that in series resonance the circuit will be purely resistive.…”

Comparative Analysis between IEEE 1459 and Conservative Power Theory Through the Development of Power Meters

“…This concept of orthogonality was demonstrated in Fryze's theory [6]. Thus, the inequality for the domestic product now proposed by Cauchy-Schwartz is defined as: (11) Another important property is the unbiased integral considering x (t) with its mean null value, represented in (12), its integral in time and unbiased will be represented in (13) and 14, respectively. 12) (13x (14) Where x  is an average value and the term described as unbiased the average value is disregarded.…”