Because voltage change in the power plant turning on/off case is higher than 5%, the amount of permissible voltage changes is limited (up to 4 times a day). As power generation depends on the level of cloudiness, the number of voltage fluctuations can increase. Because of that, the designed 1,5 MVA Solar power plant does not meet requirements for energy quality.
Based on energy quality requirements for voltage, in this particular case, it would be recommended to install a power plant that would generate voltage fluctuations at a connection point not greater than 3%. Such requirement would be met by 1,15 MVA power plants operating at PF=0 operation mode or 0,84 MVA power plants operating at PF = -0.9 mode. Since electrical network legislation requires for the power plant to be able to operate at PF ≠ 0 mode, it is only possible to connect the power plant with lower installed power.
Designed Solar power plant generated total harmonic voltages distortion at the connection point is significantly lower (0,2%) comparing to standard limits (8%), THD of harmonic currents is 0,855%.
All harmonics are within permissible limits.