Intelligent Ultra-low-power Ultrasonic Heat Meter Research And Development

There are various heat meter products in home market today. Most of them use impeller flow sensor as flow measurement unit, which need good water supply quality, the material and structure of impeller can be influenced by temperature to a great extent, and ultrasonic flow measurement accuracy is low for a domestic low flow velocity application. Considering these shortcomings, a low power consumption ultrasonic heat meter based on ultrasonic flow measurement function is designed. Looking at the tendency of international heat meter development, the demand for ultrasonic heat meter is increasing rapidly.At first, the background of study, meaning and the current study situation both at home and abroad etc. on ultrasonic heat meter are introduced. And the difficult problems urgently to be solved and main research contents have the survey introduces to the heat meter at present.Secondly, on the basis of probing into modern ultrasonic detection technique thoroughly, a new insert type ultrasonic transducer is designed, ultrasonic transducers are installed with fixed short pipe Z mode. Transducer is stimulated by lots of continuous low pressure pulses. Power is enormously reduced by the filter of magnetism link, and then there is tremendous contribution for the low-power of the whole system. As the same time, the former echo processing technology is broken through, Brand-new asymmetric RC constitution double T choosing the frequency filter network amplifier is designed as automatically increased the amplifier. In the situation of echo not distorted, the unwanted signal is filtered effectively and echo is amplified. After echo processing, echo operating point is confirmed by counts and search algorithm from the multi-pulses measuring technique. The judgment of echo is unmistakable, the accuracy of time difference measuring is increased greatly, and then precision of flow is increased. The unique sufficient charge electric discharge circuit is designed to measure the time difference of ultrasonic wave, which is a good solution for small diameter pipe and low flow velocity application. In the article, the error of ultrasonic flow measurement is made the analysis theoretically too.