What is the Displacement Coefficient?
Most light source packaging includes the term "displacement coefficient," but few people truly understand its meaning. Below, we'll use basic physics to explain in detail which core characteristics of LED light sources the displacement coefficient reflects—just ask "WATT'son," they'll certainly know everything about this.
Reactive Current and Reactive Power
For LED light sources, reactive current or reactive power is a key issue, a phenomenon caused by inductive characteristics. Reactive current causes energy to flow back and forth between the power supply and the user, commonly known as the "ping-pong effect," which has no practical value to the user.
Reactive current is not only redundant but also generates unnecessary heat, which we need to avoid as much as possible. By optimizing the internal circuitry of the power supply, reactive current consumption can be reduced to near zero.
Effective Power and Apparent Power
Active power is the actual power consumed by the device, excluding reactive power; it is the "essence" of energy consumption. Apparent power, on the other hand, encompasses both active and reactive power, representing the apparent consumption of the circuit, and is the "manifestation" of energy consumption.
This leads to a common situation where "appearance outweighs reality," meaning the apparent power value is higher than the actual usable active power.
The core definition of the displacement coefficient: The displacement coefficient is the ratio of active power to apparent power, always ranging from 0 to 1, ideally reaching 1.
The closer this value is to 1, the higher the performance and energy efficiency of the LED light source. Therefore, the displacement coefficient directly reflects the quality of the internal circuitry of the luminaire and should not be ignored—high-quality circuit design means lower energy consumption and a longer lifespan.
Would you like me to compile a table of key knowledge points about the displacement coefficient, clearly listing key terms, definitions, and practical judgment criteria?