LED harmonics are primarily caused by the characteristics of the driver power supply and load nonlinearity, potentially leading to increased grid losses and equipment interference. These issues can be mitigated by optimizing the power supply and installing filters.
I. Causes
1. Switching Power Supply Characteristics: When the switching power supply of LED lights operates, the current is input in pulses rather than flowing continuously, resulting in a non-sinusoidal current waveform and generating harmonics.
2. Nonlinear Loads: The relationship between LED voltage and current is nonlinear; LEDs only conduct when the voltage reaches a threshold, causing distortion in the current waveform and further generating harmonics.
II. Main Hazards
1. Grid Impact: Harmonics cause distortion in the grid voltage waveform, increasing transmission line losses and reducing the overall efficiency of power generation and transmission equipment.
2. Equipment Interference: Nearby electronic devices may experience screen anomalies (such as snow), communication noise, and even malfunctions in protection devices, threatening the stability of the power system.
III. Suppression Measures
1. High-Quality Driver Power Supply: Employing a meticulously designed power supply and optimizing current waveform control reduces the sources of harmonic generation.
2. Harmonic mitigation equipment: Install active/passive filters to filter and compensate for harmonic currents, making the grid input current approach a standard sine wave.
