Flickermeter on a Distribution STATCOM
This example shows a flickermeter model designed according to functional specifications of the international standard IEC 6100-4-15 [1].
Silvano Casoria (Hydro-Quebec)
Description
A flickermeter device is used to measure the instantaneous flicker sensation on terminal voltage of a STATCOM unit.
The flickermeter model is designed according to functional specifications of the international standard IEC 6100-4-15 [1]. The flickermeter is a standardized instrument for measuring the flicker obtained by simulation and by statistical analysis of the response of the lamp-eye-brain chain to the input voltage fluctuations. Reference [2] gives a detailed description of the standard block diagram. The statistical analysis (module 5 in standard block diagram) is not modeled in the block.
In order to minimize the initial transient response, the initial conditions are defined for the different transfer functions. A fixed initialization period (Tini = 0.3 s) is required between the instant the model is enabled (input ON = 1) and the computation of the results. The initial conditions calculation are evaluated in the mask initialization section of the block.
The model should be enabled (input ON > 0) after the analyzed signal (input U) is stable. The flickermeter internal outputs of the various modules are available in output m.
In practice output S (instantaneous flicker sensation) stabilizes within 2 seconds after the initialization period is started (Init signal in output m) and Output_4 (One minute dose of instant perception signal in output m) stabilizes after 2 minutes.
Module 1 contains a signal generator for checking the flickermeter setting in the field and a circuit for normalizing (in pu) the RMS value of the input voltage at network frequency (50 or 60 Hz). The generator adds a modulating voltage (fluctuating sinusoidal or triangular signal) to the fundamental (120 Vrms/60 Hz or 230 Vrms/50 Hz). Different relative amplitude (in %) and frequency of the fluctuation are defined in the standard. They should produce at Output_5 an instantaneous flicker sensation of 1.
References
[1] EC Standard 61000-4-15 Ed. 1.1 (2003) Electromagnetic compatibility (EMC)-Part4 Testing and measurement techniques-Section15 Flickermeter: Functional and design specifications [2] Bertola A.; Lazaroiu, G.C.; Roscia, M.; Zaninelli, D.;"A MATLAB®-Simulink® flickermeter model for power quality studies", IEEE® PES 11th International Conference on Harmonics and Quality of Power, September 2004, Lake Placid, USA.