TWI456244B - A wind velocity to frequency conversion apparatus - Google Patents

Claims (8)

A wind frequency conversion device includes a first capacitor; a first switch for receiving a wind voltage measured by a wind speed sensing device, wherein the first switch is turned on to generate an output voltage to charge the first capacitor, when closed The first capacitor is discharged; a comparator compares the discharge voltage of the first capacitor with a reference voltage to generate a first voltage; and a logic control circuit generates a first voltage output by the comparator through a logic operation a frequency output signal is used as the output of the wind frequency conversion device, and generates a control signal to control the conduction of the first switch; a bandgap reference circuit controls the switch to be turned on by a trigger signal Generating a first current and a second voltage; an amplifying circuit receiving the first current and the second voltage outputted by the differential reference voltage circuit and generating a reference current; and a current mirror circuit receiving the output of the amplifying circuit a reference current, and generating a second current according to the reference current; a decoder for generating a set of digital output codes according to a set of input codes; and a school The circuit receives the digital output code of the decoder, and generates a correction current for correcting the second current according to the set of digital output codes, wherein the second current is generated when the trigger signal is high logic level (high) For charging and discharging the first capacitor; when the second current is insufficient, by controlling the input code of the decoder The magnitude of the correction current is adjusted, and the second current is corrected by the correction current, and the corrected second current is charged and discharged to the first capacitor. The wind frequency conversion device of claim 1, wherein the logic control circuit comprises two cascaded D-type flip-flops and a NAND gate, wherein the first one The D-type flip-flop receives the first voltage, and the second D-type flip-flop receives the output signal of the first D-type flip-flop and generates the frequency output signal, and the reverse gate receives the two D-type positive The output signal of the counter is generated, and the control signal is generated; when the outputs of the two D-type flip-flops are all at a high logic level, the control signal of the anti-gate output will turn off the first switch. The wind frequency conversion device of claim 1, wherein the current mirror circuit comprises a plurality of complementary metal oxide semiconductor (CMOS) transistors. The wind frequency conversion device according to claim 1, wherein the wind speed sensing device is a wind cup anemometer. The wind frequency conversion device according to claim 1, wherein the wind speed sensing device is a fan-page anemometer. The wind frequency conversion device according to claim 1, wherein the wind speed sensing device is a hot wire anemometer. The wind frequency conversion device according to claim 1, wherein the wind speed sensing device is an ultrasonic anemometer. The wind frequency conversion device of claim 1, wherein the wind speed sensing device is a Doppler anemometer.