Design and Realization of Programmable Power Signal Source Based on DDS Technique

Based on the characteristics of the petroleum logging signal, the direct digital synthesis technique was applied to produce the logging exciting signal, to realize accuracy control of output signal frequency and phase. The integrated power amplification technique was used to produce the signals of high power, and power tracing technique was also used to lower the dissipation of power devices, and to improve the circuit working efficiency. With USB bus technologies the signal can be real-time controlled, the signal parameters can be real-time monitored. The results show that the output frequency of signal source is 0.01Hz ~250 kHz, frequency resolution 0.004Hz, phase resolution 0.002rad, frequency stability ±5×10 -6 per hour, output voltage scale ±75V, output current ¿6A, output power 400W. And the signal source was successfully applied in the study of the cased hole resitivity logging technique and the three-component induction logging technique.