The NTC thermistor and NTC chip developed and produced by EXSENSE Electronic Technology Co., Ltd. have the characteristics of high precision, great reliability and rapid response, which are widely used in temperature detection, temperature control and temperature compensation.
Most of the fixed-speed air conditioning on the market, its indoor and outdoor fan motors usually use AC induction motors, and outdoor motors is usually the first gear speed control. Although there is a stable rotate speed under the rated power supply of 220V and 50Hz, with the change of voltage, its speed will also appear a wide range of fluctuations, resulting in high voltage in the power grid, the noise of outdoor motor is too large; And when the voltage of power grid is low, the rotate speed of outdoor motor is too low and the heat dissipation effect is poor. In the existing technology, there is often a drift of the sensor's resistance value, which reduces the accuracy of temperature measurement, thus affecting the effect of refrigeration and heating, and affecting the working efficiency of air conditioning. In order to avoid the above deficiencies, EXSENSE Electronics introduces a type of brushless motor air conditioning system temperature detection for circuit to improve the accuracy of air-conditioning coil temperature measurement, to ensure good effect of refrigeration and heating.
Brushless motor air conditioning system temperature detection for circuits, including NTC thermistor, divider resistance, and commutation capacitor. One end of the thermistor is connected to the power supply +5V, the other end of the thermistor is connected to the microcontroller; After the divider resistance and commutation capacitor are connected in parallel, one end of them is connected between thermistor and microcontroller, the other end of them is grounded.
Brushless motor air conditioning system temperature detection for circuits, adopts NTC thermistor as the sensing element for temperature measurement, which has the advantages of wide temperature measurement range and good temperature linearity, which can improve the temperature measurement accuracy of air conditioner and ensure that the air conditioner maintains good effect of refrigeration and heating. The signal output of the thermistor is transmitted to the microprocessor after it’s voltage dividing, voltage shaping, voltage stabilizing by capacitor and resistor, and the temperature signal is collected and processed by the microprocessor, then the air conditioning motor is controlled according to the temperature value, so as to improves the operation stability and reliability of the air conditioner.