Lighthouse lighting is used in ports and large storage sites. In the past, lighthouses were mostly powered by power supply control or single lighthouse. The technical performance and economic indicators of this method are very low, and it is inconvenient for lighting dispatch management and energy saving. The cluster remote control switch designed in this paper has high stability and anti-interference ability. The remote control is equipped with a light sensor interface, which can control the opening and closing of the illumination by the light intensity.
In addition, the remote control has a timing menu, which can be turned on and off according to the set time.
1 hardware composition 1.1 remote control hardware structure The main function of the remote control is to realize man-machine dialogue, the operation interface consists of matrix scan keyboard and LCD display. It is a hardware block diagram of the remote control of the hardware structure block diagram of the radio oscillator and the reset remote control. The main core of the remote control adopts Motorola's 8-bit single-chip MCHC705B16, which has 352b RAM, 15kbOTP, 255bE2PROM, 32 bidirectional I/O, and multi-function 16-bit timer. The E2PROM of the MCU ensures that the remote controller does not lose the parameters when the battery is insufficient and the battery is replaced. Its multi-bit I/O port and powerful driving capability greatly simplify the design of the hardware circuit. The peripheral hardware circuits mainly include: crystal scanning circuit, LCD display circuit coding and RF output circuit.
The keyboard of the remote control adopts the matrix scanning structure (4x4), which is input by the PA port of the single-chip microcomputer. The menu function parameters and the keying illumination can be set on and off through the keyboard.
The LCD display is directly driven by the PB port of the MCU. The LCD displays the operands and system menus. The LCD is 1 clock when the system is not processing signals.
Coding and RF output circuits such as.
The system uses hardware coding, the encoder uses the special chip HT-12E, and its A0~A7 address line is connected with the PA port of the single chip microcomputer. According to this connection method, the total number of codes can be 28=256, that is, the remote controller can control 256 terminals. The working principle is as follows: when the MCU outputs the start signal (active low) via PC.0, the transistor T1 is turned on, triggering the thyristor SCR, so the RF transmitter is powered, and A0~A7 form a string of specific signals according to the accepted signal. The coded pulse is serially output from the DOUT terminal, amplitude-keyed modulation is applied to the RF circuit via the resistor, and the transmitter emits intermittent equal-amplitude waves.
1.2 Execution of the terminal circuit The function of the terminal is to receive the RF signal from the remote controller. After decoding the actuator, the circuit principle is composed of the RF receiving circuit, the decoding circuit, the trigger and the actuator.
The RF receiving head uses a module matched with the RF transmitter. The decoder uses the HT-12F matched with the encoder, and its A0~A7 address lines are connected to the 8-bit encoding switch to form different address codes. When the address code of the decoder is used. When the code transmitted by the remote controller is consistent, the VT port of the decoder outputs a signal, which controls the output of the trigger CD4013, so that each time the flip-flop receives the signal, the level of the output port Q2 is flipped once, by controlling T2. The turn-on and turn-off controls the pull-in and turn-off of the relay.
2 software design remote control software is mainly to achieve menu function operation and interrupt processing, the main program flow chart.
I program initialization hHLCD display 丨 remote control software main program flow chart program initialization including definition of I / O port, address code storage unit, time display unit, interrupt setting unit and menu some silent fOST limit power factor simulation analysis Introduction Switching power supply power factor correction can be divided into passive correction and active correction. Among them, the active BOOST correction circuit is the most widely used. In this paper, the simulation circuit is used to prove that the power factor of BOOST correction circuit is less than 1, and its ultimate power factor is calculated.
1 definition of power factor and BOOST power factor correction principle c) / (UI / cos: 2 is the power factor; P is the active power; S is the apparent power; /, / is the fundamental component of the mains current and the effective value, must It is the angle between the mains voltage and the current base.
Ordinary off power input side circuit, for example, its current. It can be seen that when the mains current is a peak current, the lecturer is engaged in the teaching and research of automation and power electronics.
Therefore, its harmonic current far exceeds international standards such as IEC1000-3-2, and it is necessary to use a power factor correction circuit. BOOST active correction circuit, for example, uses UC3854 as the control chip. The control chip adopts a double loop control system of a voltage outer loop and a current inner loop, UA is a current sampling end, uB is a full wave voltage and an ac voltage rm sampling end, U. is a MOSFET pulse driving end, and UD is an output voltage sampling end. When the circuit is in steady state operation, the voltage UB is approximately full-wave voltage, the current of the inductor L is approximately full-wave current, the mains current is approximately sinusoidal current, and is approximately the same frequency as the mains voltage, thereby making the switching power supply power factor close to 1. 2 BOOST active correction circuit power factor less than 1 prove that the power factor of BOOST active correction circuit is less than 1. The proof of this conclusion uses the counter-evidence method. That is, assuming that the circuit has corrected the power factor to 1, i/B should be a full-wave voltage, and the current of inductor 1 should be a full-wave current, and is the same as the 118 waveform. To this end, a simulation circuit such as is constructed. The circuit uses a current source (peak value of 12A) instead of the M, D5, C, and R2 branches, and the initial setting of the current source and the identification parameters. The menu processing program includes display time setting without signal processing, setting of timing switch function, setting of light control function, selection of address code, and the like.
The program has 3 interrupts for keying, timing and light control. The key control uses SWI software interrupt, which enjoys the highest priority. The light control uses external interrupt. The signal is input from the interrupt port IRQ of the single chip, and its priority is the lowest. Interrupt program flow chart such as.
PiVl protection site Mis takes the address code 1 sends the hair I remote control interrupt program flow Conclusion The lighting cluster remote control switch designed in this paper adopts single-chip control technology, the hardware structure is simple, the execution terminal can be expanded according to the use requirements, and the flexibility is strong. The addressing technology makes the system stable and anti-interference ability, and can be widely used in yard lighting.
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