Excitation circuit for electromagnetic log

The invention discloses an excitation circuit for an electromagnetic log, which comprises an MCU circuit, a PWM power amplification circuit, an LC filter circuit, a resonance circuit, an excitation acquisition circuit and an electromagnetic sensor, and is characterized in that the frequency of the excitation voltage of the sensor is controlled and the magnitude of the excitation voltage required by the sensor is adjusted by utilizing a programmable method; the amplitude of excitation voltage is reduced through a series resonance circuit, and the requirement of the system for a power supply is reduced. Different electromagnetic sensors matched with different resonant capacitors can be selected, the universal design of the excitation circuit is realized, the excitation circuit has overcurrent protection and overheating protection functions, constant current output of excitation current is realized through current closed-loop control, and the testability requirement of the system is improved through excitation v