# Disturbances Generated by Lighting Systems with LED Lamps and the Reduction in Their Impacts
## 3 Tests of Selected LED Lamps
Tests were conducted using a professional energy quality analyser--FLUKE 434/PWR. Current and voltage waveforms were studied using the Fluke View software. The results of the performed measurements of electrical parameters for both lamps (Table 3) were compliant with the values declared by manufacturers. The active power of LED lamp 1 was 8.3 W, and for LED lamp 2, it was 25.2 W. The values of the current crest factor \(CF_{I}\), amounting to 3.09 and 1.97 mean significant distortions of the current waveform, especially in the case of LED lamp 1. Figures 3 and 4 show oscillograms of the current and the supply voltage waveform obtained for the tested lamps. \begin{table}
\begin{tabular}{l c c} \hline \hline  & LED Lamp 1 & LED Lamp 2 \\ \hline Nominal Power \(P_{N}\) & 8 W & 25 W \\ Nominal Voltage \(U_{N}\) & 220 –240 V & 230 V \\ Frequency of Supply & 50/60 Hz & 50 Hz \\ Voltage \(f_{N}\) & & 50 Hz \\ Type of LED & COG & SMD5050 \\ Number of LEDs & 8 & 36 \\ Luminous Flux \(\Phi\) & 1055 lm & 3350 lm \\ Color Temperature \(T_{C}\) & 3000 K (warm) & 4000 K (neutral) \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Rated parameters of tested light sources. Figure 1: Oscillogram of the waveform of the voltage powering the tested LED lamps. Figure 3: Oscillogram of the waveform of voltage and current flowing through LED lamp 1. \begin{table}
\begin{tabular}{l c c} \hline \hline  & **LED Lamp 1** & **LED Lamp 2** \\ \hline RMS Current \(I_{rms}\) & 40 mA & 119 mA \\ Amplitude of Current \(I_{m}\) & 124 mA & 237 mA \\ Current Crest Factor \(CF_{I}\) & 3.09 & 1.97 \\ Active Power \(P\) & 8.3 W & 25.2 W \\ Reactive Power \(Q\) & 3.8 var & 9.7 var \\ Apparent Power \(S\) & 9.1 VA & 27.1 VA \\ Power Factor \(cos\)\(\varphi\) & 0.91 & 0.93 \\ Power Factor \(PF\) & 0.63 & 0.88 \\ Total Harmonic Distortion Ratio \(THD_{1}\) & 121.2\% & 54.1\% \\
3 rd Current Harmonic Level \(h3\) & 88.5\% & 46.4\% \\
5 th Current Harmonic Level \(h5\) & 60.4\% & 11.0\% \\
7 th Current Harmonic Level \(h7\) & 38.7\% & 15.2\% \\
9 th Current Harmonic Level \(h9\) & 36.3\% & 6.1\% \\
11 th Current Harmonic Level \(h11\) & 30.5\% & 9.7\% \\
13 th Current Harmonic Level \(h13\) & 23.4\% & 8.6\% \\
15 th Current Harmonic Level \(h15\) & 16.8\% & 6.1\% \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Results of measurements of electrical parameters for the tested LED lamps. Figure 2: Spectral characteristic of higher harmonics of voltage supplying the tested LED lamps. Measurements of the current higher harmonics for the tested LED lamps confirmed the suppositions resulting from the observation of the oscillograms. LED lamp 1 generates high initial levels of uneven current higher harmonics _h3_, _h5_, and _h7_, which have the strongest impact on the current waveform distortions, these were at the following values: 88.5%, 60.4%, and 38.7%, respectively. The level of the third harmonic exceeds the permissible limit determined in [50]; therefore, the use of the lamp on the European market should not be allowed. In the case of the second tested lamp, the results of the measurement of the current higher harmonics are clearly lower and are within the limits of normatively permissible values (_h3_ = 46.4%, _h5_ = 11%, and _h7_ = 15.2%). These are, however, still very high values of current harmonics, which may have a negative effect on supply voltage distortions or the safety of the electrical system and other loads. The total harmonic distortions in current \(THD_{I}\) for the tested lamps amounted to 121.2% (LED lamp 1) and 54.1% (LED lamp 2). Consequently, the second light source clearly affects deterioration in the power quality parameters to a lesser extent. The presence of higher harmonics is also proven by the lower value of the power factor _PF_ (which takes into account higher harmonics) in relation to the power factor _cos_\(\varphi\) (only for basic components).