| 摘要 |
<p>The invention relates to an analogue electronic transducer used for measuring power in direct current circuits. According to the invention, the transducer consists of a circuit for generating the filling factor which is an astable flip-flop circuit based on an amplifier (A) with positive reaction through two resistors (Rand R) but also with negative reaction through two diodes (dand d), two equivalent controlled resistors (rand r) and a capacitor (C), the equivalent resistors (rand r) corresponding to some bipolar transistors from two oppositely-connected optocouplers, the output voltage of the differential amplifier (A) controlling, in synchronism, two electronic switches (Kand K) connected with two low-pass filters (FTJ-1 and FTJ-2) which have the role of smoothing the rectangular waves generated by the switches (Kand K) and an amplifier (A) which controls the current of the diodes (dand d).</p> |
