Examples of international flicker requirements in high voltage networks and real world measurements

Abstract

Comparing flicker planning levels and flicker requirements given by utility companies world wide, it can be found that there are great differences in these planning levels and thus in requirements to companies which have installed flicker generating equipment such as arc furnaces, welders etc. Taking into account that the flicker immunity of equipment, connected to LV systems and the flicker sensitivity of inhabitants of residential customers are more or less equal in a globalized world, there is no real reason that in certain areas, resp. in certain standards the planning levels are extremely low. In this case such planning levels can give remarkable competitive disadvantages for the industry, if companies have to reduce e.g. the furnace power or have to install expensive additional compensation equipment, e.g. statcom systems.The aim of this paper is, to compare international resp. national planning levels for flicker in high voltage networks and the flicker requirements which must be fulfilled by customers running flicker generating equipment like arc furnaces. It can be shown that in many cases the real flicker values in high voltage networks, which are supplying towns with industrial areas, are much higher than the planning levels without creating complaints by private consumers. This shall be proved using results of "real world" flicker measurements.The real world examples prove that flicker values in high voltage systems can be much higher than the usual planning levels without causing complaints by residential customers which are supplied via medium voltage and low voltage from these systems. This fact is already taken into account by some utilities but unfortunately it has not yet found access to the national and international standards or recommendations. On this field there is still much work to do.

Flicker propagation and emission coordination study in a simulated low voltage network

“…However, in reality, the P lt values are always lower than the P st values. The P lt values are calculated on a 2 hours basis, by summing up the 12 numbers of consecutive 10 minutes P st values, as shown in Equation (4).…”

Measurement of Voltage Flicker: Application to Grid-connected Wind Turbines

“…There have been very few studies contrasting field measurements of flicker and the level of annoyance perceived by people. The work (Arlt et al, 2007) compares the international planning levels for flicker in high-voltage networks and the flicker requirements that must be fulfilled by customers running flicker-generating equipment. They show that in many cases, the real flicker values in high-voltage networks, which are supplying towns with industrial areas, are much higher than the planning levels without causing complaints by residential customers who are supplied via medium voltage and low voltage from these systems.…”

Benchmarking of Power Quality Performance in Transmission Systems - CIGRE WG C4.27 perspective

“…Comparative measurements between P st_max values and ΔV10 (4 th ) give a ratio of 3 for those applications [15].…”