Halliburton Energy Services, Inc.

Zheng Chen

Batakrishna Mandal

Peng Li

Boguslaw Wiecek

An example cement and casing evaluation tool includes an amplifier and a filter coupled an output of the amplifier. A transducer may be coupled to the output of the filter. A ringing reduction system may be coupled to at least one of the amplifier, the filter, and the transducer, wherein the ringing reduction system selectively dissipates energy from at least one of the amplifier, the filter, and the transducer in response to a control signal.

Casing and cement evaluation tool with reduced transmitter ringing

An example method includes determining a frequency response of a tuned pulse to be transmitted from a transmission element. A matching frequency envelope corresponding to a frequency envelope of the frequency response may be determined. A time domain signal corresponding to the matching frequency envelope may be determined. A series of digital pulses corresponding to the time domain signal may be determined. An analog output at a switching amplifier corresponding to the series of digital pulses may be generated. A transmission element may be excited with the analog output.

Pulse generation for downhole logging

A pulse-transformer-based isolated gate driver circuit uses a small count of high-temperature-qualified components to drive a power semiconductor switch with asymmetrical voltage biases. A differential driver generates a pulse signal from a pulse-width-modulated signal, which is passed to a charge and lock circuit through a transformer. The charge and lock circuit includes an activation path and a deactivation path, which are selectively open to current flow based on positive or negative voltage pulses in the pulse signal, to selectively turn the main semiconductor switch on or off. The charge and lock circuit can lock voltage across the main semiconductor switch to keep the main semiconductor switch in an 'on' or and 'off' state.

Growing community of inventors

Katy, TX, United States of America

Zheng Chen