The working principle of energy-saving lamps LED energy-saving lamps circuit diagram explanation
1. The working principle of energy-saving lamps
Energy saving, in this The era of high energy consumption is obviously a top priority, and many countries regard energy conservation and emission reduction as the primary task of industrial construction and urban transformation. So as an energy-saving lamp encouraged by the state, what are its structural components? How does it work? Let me explain it to you one by one!
The energy-saving lamp is actually a compact fluorescent lamp with its own ballast. When the energy-saving lamp is lit, the electronic ballast first heats the lamp filament, and the filament starts Electrons are emitted (because some electron powder is coated on the filament), and the electrons collide with the argon atoms filled in the lamp tube. After the collision, the argon atoms obtain energy and then hit the mercury atoms inside. The mercury atoms undergo transitions after absorbing energy to generate ionization. A plasma state is formed in the lamp tube.
The voltage at both ends of the lamp tube is directly turned on through the plasma state and emits ultraviolet rays of 253.7nm. The ultraviolet rays excite the phosphor to emit light. Since the temperature of the filament is about 1160K when the fluorescent lamp is working, it is higher than the working temperature of the incandescent lamp. 2200K-2700K is much lower, so its life is also greatly improved, reaching more than 5000 hours. Because it uses electronic ballasts with high efficiency, and there is no current heating effect like incandescent lamps, the energy conversion efficiency of phosphors is high, reaching More than 50 lumens per watt, so save electricity.
Second, LED energy-saving lamp circuit diagram
The LED energy-saving lamp circuit diagram introduced in this article uses a 220V power supply to supply power, and the 220V exchange power is stepped down by a C1 step-down capacitor. , after full-bridge rectification, after filtering through C2, the current limiting resistor R3 provides constant current power to 80 LEDs connected in series (the principle of energy-saving lamp circuit diagram)
Figure 1 led Circuit diagram of energy-saving lamp
Figure 1 is a practical circuit diagram of a SMD LED lighting fixture. The lamp is powered by a 220V power supply, and the 220V alternating current is stepped down by a C1 step-down capacitor and then rectified by a full-bridge and then filtered by C2. Afterwards, a constant current power supply is provided to the 10 SMD LEDs connected in series through the current limiting resistor R3. The rated current of the SMD LED is 20mA, but we need to consider the influence of many factors on the SMD LED when making energy-saving lamps, including the problem of light decay and heat generation. The temperature of the LED has a great influence on the light decay and life. If the heat dissipation is not good, it is easy to cause light decay, because the characteristic of LED is that the temperature will increase and the current will increase, so the problem of heat dissipation is the most important when doing high-power lighting, which will affect the stability of the LED. , Small power usually adopts self-heating method, so the current should not be too large during circuit design. In the figure, R1 is the shielding resistor, R2 is the discharge resistor of the capacitor C1, R3 is the current limiting resistor to warn that the voltage increases and the temperature increases the LED current increases, and C2 is the filter capacitor. In fact, the filter circuit can be used in the LED circuit. C2 is used to guard against the impact of the current on the LED when the light is turned on. At the moment when the light is turned on, there will be a large charging current due to the existence of C1. The current flowing through the LED will cause damage to the LED. With C2 With the intervention, the charging current of turning on the light is completely absorbed by C2, which acts as a protection against attack when turning on the light. This circuit is the most practical circuit for low-power lamp cups. It occupies a small volume and can be easily installed in a lamp cup with a small space. Now it is widely accepted by lamp cup products. Advantages: constant current source, low power consumption, small size, economical and practical. However, in the design, the step-down capacitor should use polyester capacitors or CBB capacitors with a withstand voltage of more than 400V, and the filter capacitors should use a withstand voltage of more than 250V. This circuit properly drives 7-12 20mA SMD LEDs.
