Improvement of Power Quality and Reliability with multifunctional PV-inverters in distributed energy systems

Abstract

The share of distributed generation (DG) within the distribution network increases strongly. A lot of these DG units are driven by Renewable Energy Sources (RES). Up to now, these units only inject active power depending from the availability of their primary source. In future on the one hand DG units have to contribute to grid stability, but on the other hand DG units can provide additional functionalities in order to offer a surplus value for the customer. Therefore especially inverter-coupled systems are well suited. Additional functionality could be improvement of Power Quality and Reliability (PQR), but also peak shaving, provision of control energy or reactive power compensation is conceivable. This paper presents several approaches of such multifunctional inverter systems developed by ISET e.V., SMA and TU Sofia with the focus on PQR.

Analysis of Active Harmonic Compensation Algorithms for Grid-Connected Photovoltaic Inverters / Aktyvusis Harmonikų Kompensavimas Saulės Elektrinių Tinklo Inverteriais – Algoritmų Analizė

“…Pagrindinis PE tikslas yra tiekti aktyviąją energiją į elektros tinklą priklausomai nuo pirminio energijos šaltinio galimybių. Tačiau PE gali ne tik suteikti galimybę naudotis nuolatinėmis elektros energijos atsargomis, bet ir padėti gerinti elektros tinklo energijos kokybę -sumažinti tinkle atsirandantį mirgėjimą, įtampos svyravimus, harmoninį iškraipymą ir spręsti kitas elektros energijos kokybės problemas (Geibel et al 2009). Šiuo metu PE, kurios į elektros tinklus įjungtos per galios keitiklius (pvz.…”

A Review on Power Quality in Grid Connected Renewable Energy System

“…Experimental outcome of a singlephase laboratory setup (2 kVA inverter) is illustrated in [7] to explain phase-synchronized grid voltage with the help of kalman filters. Recently Multifunctional PV Inverters for micro grid applications are coming up to introduce the reliability as an additional objective [8].…”

“…Papers [22][23][24][25] highlight the power electronic solutions for GCSPV applications. PV module is connected to the inverter which is directly fed to the grid, so without using batteries it will supply the energy during day-time, reducing the cost of the system and maintenance.…”

Power Quality in Grid connected Renewable Energy Systems: Role of Custom Power Devices

“…A multifunctional PV Inverter for a grid connected system (Fig 3) has been developed recently and presented in [15]. This system demonstrates the reliability improvement through UPS functionality, harmonic compensation, reactive power compensation capability together with the connection capability during the voltage sag condition.…”