Comparison of push-pull and half-bridge resonant inverters for cold cathode fluorescent lamps

Assessment of Conducted Emission for Multiple Compact Fluorescent Lamps in Various Grid Topology

“…Since the operation of lamps operates at nonconstant switching frequency. Hence, this characteristic affects the impedance hence the voltage stability of the network that it is connected to because the impedance is the function of frequency, 2 which is determined by the real value resistance, R and capacitive, in its parallel-resonant circuit [32,33]. These resonant converters in these CFL lamps connected in same network can cause the impedance of the grid to continuously fluctuate.…”

“…In contrast to most power converters where their switching frequency is fixed which is driven by high precision crystal oscillator with negligible frequency tolerances. However, the output for the gas discharge type CFL lamp operates at unfixed resonant switching frequency [32,33], the observed operating switching frequency range is between 37 kHz to 47 kHz for this lamp, a line impedance stabilization network (LISN) is used for isolating the test setup from the interference outside of the setup and provide constant impedance during the measurement. The differential mode (DM) signals were measured using a Gauss™ TDEMI receiver that is connected to an insitu EMI monitoring device (MD) developed by [29,34].…”

Characteristic of Conducted EMI in Compact Fluorescent Lamps Application Assessment based on CISPR-11

“…In this case, a measurement with narrow IFBW can produce different results altogether. For instance in the case of the electronic ballast CFL lamp which is driven by low power-factor (PF) parallel-resonant circuit, the circuit operates with a fluctuating switching frequency in a wide bandwidth resulted from accuracy of its` RLC components [12] [13]. The switching frequency sweeps randomly across wide bandwidth in a skewed distribution pattern.…”