Study on the application of simulated inductor technique to the design of C4D sensor

This work focuses on the study of the application of simulated inductor technique to the design of C4D sensor. A grounded simulated inductor, which is on the basis of the classic Riordan simulated inductor, is designed. With the grounded simulated inductor, two kinds of C4D sensors based on series resonance principle are developed. One is the new C4D sensor A, which implements the conductivity measurement by the current-to-voltage conversion. The other is the new C4D sensor B, which implements the conductivity measurement by the measurement of the differential voltage. Conductivity experiments were carried out in four pipes with inner diameters of 2.2 mm, 3.0 mm, 4.6 mm and 6.4 mm. The experimental results show that the designs of the grounded simulated inductor and the two kinds of new C4D sensors are successful. The experimental results also indicate that the sensitivity and the input-output characteristic of the C4D sensor A are better than that of the C4D sensor B. Besides, compared with a practical inductor, the grounded simulated inductor has a comparable performance and has the advantage of adjustable equivalent inductance. The research results obtained in this work can provide a useful reference for the further study of C4D sensor.