Introduction to the basics of LED driver power supply

来源: | 作者:OTM-Viwen | 发布时间 :2024-08-01 | 40 次浏览: | Share:

Introduction to the basics of LED driver power supply

What is LED driver power supply?

LED drivers are used to power lamps. Under normal circumstances: the input of the LED driver power supply includes high-voltage industrial frequency AC (i.e., mains), low-voltage DC, high-voltage DC, low-voltage high-frequency AC (such as the output of an electronic transformer), etc. The output of the LED driver power supply is mostly a constant current source that can change the voltage as the forward voltage drop value of the LED changes. The core components of the LED power supply include switch controllers, inductors, switch components (MOSfet), feedback resistors, input filter components, output filter components, etc. According to the requirements of different occasions, there must also be input overvoltage protection circuits, input undervoltage protection circuits, LED open circuit protection, overcurrent protection, and other circuits.

Characteristics of LED driver power supply

High reliability

Especially the driving power supply of LED street lamps, which is installed at high altitudes, is inconvenient to maintain and the maintenance cost is also high. When there is no shelter outdoors, it is necessary to choose a high-temperature and waterproof LED driver.

The IP Rating of LED drivers are:

IP20 drivers need to be placed in a dry indoor location for use.

IP44 drivers are suitable for indoor humid environments or outdoor covered places, such as bathrooms, kitchens or semi-open balconies.

IP65 drivers are suitable for outdoor environments such as garden lighting, open spaces, etc., and can withstand normal rain and spray.

IP66 drivers are suitable for more severe outdoor environments, such as building exterior lighting, ships and docks, etc., which need to be protected from the impact of strong water flow.

IP67 drivers are suitable for environments that may be immersed in water for a short period, such as poolside, outdoor landscape lighting, etc.

IP68 drivers are suitable for long-term water immersion environments, such as underwater lamps, fountains, pond lighting, etc.

The corresponding protection level can be selected according to the usage environment of the lamp.

High efficiency

LED is an energy-saving product, and the efficiency of the driving power supply must be high. It is imperative to heat the junction of the power supply installed in the lamp. The higher the efficiency of the power supply, the less power it consumes, converting more input electrical energy into useful output electrical energy, reducing energy loss, and the lost capacity will be converted into the form of heat energy, so the higher the conversion efficiency, the higher the temperature. Low, the power supply lasts longer. Ottima LED Driver efficiency is from 85-95%, which Varies with wattage.

High PF

PF saves energy efficiency for the national grid and has nothing to do with usage. It reflects how much of the electrical energy provided by the grid is effectively used by the drive. High power factor means less reactive power (reactive power) consumption, which is friendly to the grid.

Normally is low PF0.6, and high PF0.9, PF does not affect quality, it affects energy consumption in this country, Some European countries will require PF>0.9, which can save the national power grid.

Power supply classification

There are 2 different LED drivers in the market, Constant current--The current of this power supply is fixed, and The output voltage is a range, Such as 500mA 20-30v.

Another type is constant voltage, The voltage of this power supply is fixed and is usually a multiple of 12, Such as 20w 12v, 30w 24v, or 60w 48v...Now constant pressure has become the mainstream of the market.

Surge protection

LED driver Surge Protection refers to protecting the LED driver and its connected LED lamps from the effects of instantaneous high voltage (surge). These high-voltage surges are often caused by lightning strikes, power system switching, or other electrical disturbances. Surge protection can reduce the risk of electrical failures and fires caused by surge voltages, improve the safety of electrical systems, and reduce the frequency of replacement and repair, thereby reducing maintenance costs.

Protective function

Over Voltage Protection, OVP

Prevents input voltage or output voltage from exceeding preset values, thereby protecting drivers and LED fixtures from high voltage damage and shortened service life

Over Current Protection, OCP

When the current exceeds the preset safety value, the driver will automatically limit or cut off the output current to prevent circuit overheating, damage or fire risks caused by excessive current.

Short Circuit Protection, SCP

When a short circuit at the output is detected, the driver will quickly cut off the power supply to protect the internal circuit and connected LED lamps from overcurrent and possible electrical fires caused by the short circuit.

Over Temperature Protection, OTP

When the internal temperature of the driver exceeds the safe range, the driver will reduce the output power or turn off the power supply until the temperature returns to normal. It can prevent component aging, damage or failure caused by excessive temperature.

Reverse Polarity Protection

Prevent circuit damage caused by reverse connection of the power cord.

Under Voltage Protection, UVP

When the input voltage is lower than the preset value, the driver will stop working to prevent abnormal behavior caused by voltage instability.

Output Over Voltage Protection

When the output voltage exceeds the set range, the driver will limit or cut off the output voltage to prevent excessive output voltage from damaging the LED lamps.

Soft Start

When the driver starts, the output current gradually increases to the normal level to reduce the current surge at the start-up moment. It can extend the service life of LED lamps and drivers and reduce the impact on the power grid.

Electromagnetic Compatibility, EMC

Reduce the electromagnetic interference generated by the driver during operation and avoid affecting the normal operation of other electronic equipment.