LED Power Supply

The technical specification of a new type and long lifespan LED power supply

Aiming at changing the reality that the life span of present outdoor type LED power supply is shorter than 10,000 hours, we have designed the brand-new semi-permanent life-time product. With no electrolytic capacitor and adopting current type system control, our products offer full guarantee to the life and reliability of outdoor type LED power supply.

The designed life-time is more than 50,000 hours and the operational temperature ranges meet the requirements of American military standards. Quality assurance is 5 years.

The 8,000 sets mass production experiment proves that the spread of the product’s external characteristic technical specification is within 3%; the failure probability of the product before and after being aged is <3‰, which reaches the original designed performance specification. Among the failure probability, 40% is caused by the quality of the devices while 60% is welding procedure problems and no design problems are found.

As there is no independent PFC circuit and electrolytic capacitor, the output character of the newly designed LED driving power has distinctive difference from the current products in the market. The output index is increased; the following are the indexes of voltage standing wave ratio and energy traveling-wave coefficient:

1. Output voltage standing wave ratio and energy traveling-wave coefficient:
The voltage standing wave ratio: 1.33
The energy traveling-wave coefficient: 0.75

Explanations: the explanation and illustration about the two output character indexes

1. Output voltage standing wave ratio is the ratio between the maximal output voltage and minimal output voltage in each period(power frequency 50HZ corresponding to 10mS)
2. Energy traveling-wave coefficient is the coefficient between the effective energy and the maximal energy in each output period. For example, the AC power frequency directly provides power to resistance only after it is rectified (AC constant voltage power supply), its energy traveling-wave coefficient is 0.707; while the AC power frequency directly provides power to LED only after it is rectified (AC constant voltage power supply), which the effective current value is equal to the rated value of LED, its energy traveling-wave coefficient is 0.30 under which naked eyes cannot observe stroboscopic phenomenon.

3) Note: As for the LED power supply with no electrolytic capacitor and PFC circuit structure, its energy traveling-wave coefficient is of the most importance. It determines the current character of LED luminescent as pulsating current while its energy traveling-wave coefficient should be controlled above 0.60. Because of LED characters, its life-time will be assured. From the above pictures we can see that the output characters of LED driving power is more ideal when it operates among small range of network voltage, such as inputting AC110V±20%.

The characters of LED power supply’s circuit structure designation: in addition to meet the public lighting requirements, the LED power supply has the features of simple circuit structure, high reliability, long life, adapting into high and low temperature, and low cost; as the power factor is not high under the condition of full network voltage operation, its current characteristic can illustrate the valley point, which has compensation action.