Single-Phase Photovoltaic-Inverter Operation Characteristic in Distributed Generation System

Abstract

Single-phase grid tied inverter is one among types of inverters widely used in photovoltaic (PV) generation system due to the advantages they offer. This chapter describes model and simulation of such inverter in operation as distributed generation in electrical power system. Power characteristics including power quality, grid interaction behavior and load sharing that are important aspects in their operation as grid connected inverter will be simulated and analyzed. The role of current or voltage control and associated mechanism in photovoltaic inverter such as photovoltaic I-V characteristic, maximum power point tracker (MPPT), and other mechanism that involves in power flow and load sharing control are described. Further, some observation and measurement from a 5-kWp laboratory scale grid interconnected photovoltaic plant that employ single phase photovoltaic inverter will be presented. The load sharing behavior between photovoltaic plant and utility grid during supplying both linear and non linear load that connected on their point of common coupling. In addition, observation and measurement results of power quality parameter behavior during photovoltaic inverter operation along extremely density variation of photovoltaic produced energy that comes from the atmospheric condition will be presented.

Electrical Generation and Distribution Systems and Power Quality Disturbances

“…( (6) Analysing the (6), it can be seen that the LPSP, in stand alone systems supplied by a generically hybrid renewable power plants with a storage systems, depends mainly on two design aspects: sizing of the renewable generators and of the storage system and to the control strategies adopted for the energy management. A compromise between the power quality of the electrical supply and the costs of the system should be reached in the designing of renewable power plants in particular the use of a fuel generation unit to supply the load in case of a lack of energy from the renewable energy sources and the storage system can decrease the LPSP of the system up to zero.…”

“…The relationship (6) expresses the probability that the event will occur in time interval (0, t) or as they say in the theory of reliability is the probability of the OEL functioning without fault until t moment.…”

“…In the paper (Baron et al,1988), the authors presents a practical mathematical method of setting the α and β parameters with two parameters of Weibull law by the form of relationship ( 6), based on statistical data obtained from the analysis of operating arrangements of the OEL, as well as in the following assumptions: a. there are significant records concerning the concerning to the number of defects and the operating times between them; b. the average recovery times are negligible compared with the operating times. The value of the parameters 'α' and 'β' is derived from the relationship (6), which by logarithm application, results as:…”

“…Fluctuation of weather condition, variations of loads and grids, connecting PV-based inverters to the power system, requires power quality control to meet standards of electrical utilities. PV can reduce or improve power quality levels [6][7][8][9]. Different aspects should be taken into account.…”

“…In Modified ramp type current controller switching frequency is limited, also maintain switching frequency constant. This controller ramp signal is generated at particular frequency to maintain switching frequency constant [4], [5], [6].…”