How to test the LED driver power supply?
Compared with traditional energy-saving lamps, LED lamps have higher light efficiency and are more environmentally friendly. LED drive power supply is the AC power supply or other DC power supply into LED lamps available constant voltage or constant current specific power supply, LED drive power supply is one of the core components of LED lighting, its performance and reliability directly determines the use of LED lighting effect and life. In order to be better used in LED lighting, in the development or production stage of LED drive power, it is necessary to adopt appropriate test scheme to test the indicators of LED drive power.
Introduction to LED driver power supply test
LED drive power manufacturers in order to further improve the performance indicators of LED drive power, and to ensure the good quality of the factory products, usually need to go through a strict testing process, which includes input test, output test, protection test, safety test, environmental test and EMC test and a wide variety of test items.
1, energy efficiency,
High efficiency LED is an energy saving product, and the efficiency of the driving power supply is high. Power efficiency is more important for lamps with internal power supply. Because the luminous efficiency of LED decreases with the increase of LED temperature, the heat dissipation of LED is very important. The efficiency of the driving power supply is high, its power loss is small, and the heat is small in the lamps and lanterns, which reduces the temperature rise of the lamps and lanterns.
2, power factor
Power factor is the load requirements of the grid. With the continuous improvement of the demand for power supply quality, the power quality and harmonics caused by electrical equipment are paid more and more attention. "LED module with AC electronic control device energy conservation certification technical specification" for the LED control device energy efficiency limit value has been stipulated, the line power factor is the lowest 0.7.
3. Output ripple
Ripple is the AC voltage applied to the DC output voltage and is also an important measurement parameter in LED power supply testing. The larger the ripple current is, the performance of LED will be affected, and even the service life of LED will be seriously reduced.
4. Input surge current
LED drive power supply should have the ability to suppress the inrush current to protect the LED from being damaged. The input surge current is generally at the cold start, when the AC voltage is at the peak (90° or 270°), the surge current maximum. Important components of LED power supply, such as input fuses, rectifiers, etc., are generally rated higher than the input surge current value.
5. Abnormal test of input power supply
The main purpose of the input power supply anomaly simulation of the LED driver is to assess whether the LED driver can meet the requirements of the voltage immunity test section of the EMC test, which can be referred to IEC 61000-4-11: Voltage Skips, Short Interruption and Voltage Variation immunity tests.
In order to accurately evaluate the performance indicators of LED drive power and verify whether each test item meets the technical requirements, it is necessary to select the appropriate LED drive power test scheme.
LED drive power test scheme
The LED drive power test items include a series of parameters such as AC input range, power efficiency, power factor, ripple and noise, start and hold time, rise time, overload protection, overvoltage protection, electromagnetic compatibility and so on. LED drive power is a switching converter, so energy efficiency test needs to be able to accurately measure the power and power factor of the distortion waveform; In addition, the measuring instrument is required to have sufficient bandwidth to avoid the measurement error caused by filtering out the high-frequency current components.