Power saving lighting control system based on single chip microcomputer

China's lighting electricity accounts for about 12% of the total electricity generation, and mainly to inefficient lighting, so it becomes one of the main objects of the terminal power saving. Most of the electricity used for lighting belongs to the peak power, which shows that the lighting energy saving has the dual function of saving electricity and easing the peak power consumption. The principle of work is to promote the lighting energy saving, which is not to reduce the requirement of visual work and reduce the lighting quality.

At present, the development of China's electric power industry is very fast, but the shortage of power supply and the low efficiency of electricity consumption is still serious, and will continue to exist for a long time in the future. Energy saving technology is one of the main ways to improve the condition of power load. China's lighting electricity accounts for about 12% of the total electricity generation, and mainly to inefficient lighting, so it becomes one of the main objects of the terminal power saving. Most of the electricity used for lighting belongs to the peak power, which shows that the lighting energy saving has the dual function of saving electricity and easing the peak power consumption. The principle of work is to promote the lighting energy saving, which is not to reduce the requirement of visual work and reduce the lighting quality. The basic principle of energy-saving lighting should ensure the visual requirements without reducing the workplace, under the premise of ensuring the quality of lighting and illumination standard, and strive to reduce the energy loss in the lighting system, the most effective use of electricity.

The relationship between the service life of the lamp and the voltage is as follows:

According to the above 100W bulb rated life of 3000 hours, the actual service life is:

In type:

P - the actual power consumption of the lamp source

WPN - the power consumption of the lamp source rated voltage

WV - the actual operating voltage of the lamp source

VVN - lamp source rated voltage

VH - the actual service life of light source

HN - rated service life of light source from the above, power saving is a feasible method, not only saves energy, and the voltage stability, prolong the service life of the bulb, energy saving double sense.

According to the characteristics of fluorescent lamps, the need to start at the instantaneous high voltage to light, only after the start of a low voltage can be maintained. This is based on the characteristics of energy saving controller of fluorescent lamp, in the initial stage of the electric power network, the 220V voltage output, such as fluorescent lamps after stable operation to lower 200V, 190V or 180V low voltage output. The operating mode for the power saving controller: Saver began to work, first of all to full voltage operation in preheating time preset; preheating time after the output voltage of the electric start smoothing down, until the output voltage to the electricity level preset, and maintain the level of stable operation, when the electricity level setting value changes or saving the control signal is disconnected, the output voltage will change to a new level of power saving or restoring full voltage output hardware design includes power part, MCU and its peripheral circuit, current sampling circuit, voltage sampling circuit and driving circuit. The electrical system consists of 13 parts of the power transformer, the input AC 220V, output are 200V, 190V, 180V, plus 220V, a total of four. Relay J2, J3, J4 and J1 control. The purpose of controlling the output voltage can be achieved by controlling a specific relay. The relay J5 is connected to the current transformer. When the current is too large, the relay J5 is closed, so that the current flowing through the transformer is not too large. Single chip microcomputer and its peripheral circuit AT89C52, which contains 256 bytes of RAM, 32 I/O lines, the 3 bit timer / counter, and comes with the 8K EEPROM electric erase, in order to save the control program. Using ADC0809 as the ADC, the current and voltage conversion from analog to digital, the clock is ALE MCU by D flip-flop frequency control circuit to control the shrinkage, the mouth is composed of P2.7, WR, RD and non standard output by delay results, time delay is about 180s. MCU P0 port and ADC0809 output port connection, read the results of AD conversion. Sampling circuit and drive circuit system according to the voltage and current of the grid, make the corresponding control strategy, so sampling is essential. The current transformer is used as a current detecting element, which can reflect the current in the main circuit, and can separate the control circuit from the main circuit, improve the safety and reduce the interference.

The current in the transformer is rectified, converted into current and voltage, filtered and calibrated, and then output to the analog to digital converter ADC0809. Voltage sampling through the transformer to collect the grid voltage, the transformer also has the role of isolation, the collected voltage after rectification, filtering, calibration output to ADC0809. The output pulse of the single chip microcomputer can be directly connected to the relay control level after isolation and power amplification. In order to reduce the interference from the power grid, the trigger pulse generated by the I/O line must be isolated to the relay control circuit. Relay J1~J4, at the same time, there is only one relay closed, so there are eight states. SCM three (P1.0~P1. 2) by the decoder after the conversion of the eight control signals can be obtained, these signals are used to control the relay after the amplification of the action of the. When the relay is not required, the output of the 38 decoder can be turned off by P1.3. X5045 due to system parameters, so the selection of a X5045, it contains 512 8 bit EEPROM, serial communication with the MCU, can set parameters to save power, the on-chip SPI memory for storing the preset value and the operation level of power saving period setting value. In addition, the utility model also comprises a programmable watchdog timer and a low voltage detection circuit, which can protect the singlechip to run reliably. The software design uses the modular design idea, with the main program as the core set up a lot of function module subroutine, so that a large number of functions in the subroutine, simplifying the design structure. In the process of running, the function modules are called by main program.

The design principle of the power saving system is novel, the hardware is simple, and the power saving effect is very good. The experimental results show that the energy saving efficiency is 25%, the system not only has the function of saving electricity and prolonging the service life of the lamp, but also can make the fluorescent lamp run stably in the range of voltage fluctuation. Because the system is controlled by single chip microcomputer, it has high performance price ratio and flexibility, which can be changed and extended according to the actual situation.