Selective Compensation in Four-Wire Electric Systems Based on a New Equivalent Conductance Approach

• Published in: IEEE transactions on industrial electronics (1982) Vol. 56; no. 8; pp. 2862 - 2874
• Main Authors: Orts-Grau, S., Gimeno-Sales, F.J., Segui-Chilet, S., Abellan-Garcia, A., Alcaniz-Fillol, M., Masot-Peris, R.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.08.2009; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Buses (vehicles); Bypasses; Cancellation; Compensation; Conductance; Control systems; Direct current; Electrical installations; Electrical quality; Equivalence; harmonic compensation; Inverters; Medium voltage; Network topology; Power industry; Power measurement; Power system management; reactive compensation; Reactive power; Resonance; selective compensation; Shunts; Wire
• ISSN: 0278-0046; 1557-9948
• DOI: 10.1109/TIE.2009.2014368

This paper presents a new calculation method to obtain the reference currents for a selective shunt active power compensator (APC) with the capability of distinguishing between selective and global operating modes. This selective compensation operation is done through an identification of the current terms related to the physical phenomena that exist in electrical systems following a new equivalent conductance concept. Through this identification, this paper proposes the adequate set of reference currents that, used by a shunt APC (SAPC), achieve the selective cancellation of a desired nonefficient phenomenon. Furthermore, by combining the different current terms, it is possible to derive the sets of reference currents that allow the cancellation of a desired combination of nonefficient phenomena. By using these reference currents, a selective compensation feature is added to the SAPC control. An SAPC based on a three-phase three-leg inverter with a split dc bus has been implemented. The neutral wire of the electrical installation is connected to the midpoint of the dc bus, so the selective SAPC is able to work in four-wire electrical systems. The experimental results obtained demonstrate that the proposed selective compensation properly works in three-phase electrical systems with load-current unbalances, voltage asymmetries, and harmonic components. The electric quality is improved with the use of the proposed selective control based on this new equivalent conductance approach.