Rotary pulser with regenerative control

1 . A method for operating a pulser at a down hole location in a well bore in an earthen formation, the pulser being in fluidic communication with a drilling fluid, the method comprising:

operating a first motor of one or more motors of the pulser in order to rotate at least one rotatable element of the pulser, wherein rotation of the at least one rotatable element generates a pressure pulse in the drilling fluid;

supplying a first electrical energy to the first motor to rotate the at least one rotatable element as the first motor is operating;

taking a measurement to determine a position of the at least one rotatable element and sending the measurement to a control processor of the pulser, wherein determined position of the at least one rotatable element is used to determine opening and closing of at least one switch to a battery module or a capacitor bank of the pulser;

initiating a signal to stop the first motor in order to stop rotation of the at least one rotatable element of the pulser;

in response to receiving the signal, stopping the first motor to stop rotation of the at least one rotatable element;

receiving a second electrical energy from the first motor as the first motor is stopping the rotation of the at least one rotatable element; and

directing with the control processor of the pulser at least some of the second electrical energy to the capacitor bank of the pulser.

2 . The method of claim 1 , wherein the first motor is a direct current (DC) motor.

3 . The method of claim 2 , wherein the DC motor is at least one of: a brushless DC motor, an un-commutated DC motor, a permanent magnet DC motor, or a wound-stator DC motor.

4 . The method of claim 1 , further comprising:

producing, by the first motor, the second electrical energy during the stopping of the first motor.

5 . The method of claim 1 , wherein

determining, by the control processor, that the received second electrical energy is substantially the same as a motor energy threshold; and

switching, by the control processor, the second electrical energy to the capacitor bank upon the determining that the received second electrical energy is substantially the same as the motor energy threshold.

6 . The method of claim 5 , further comprising:

determining, by the control processor, an electrical energy level of the capacitor bank is at least one of: substantially the same as a capacitor energy threshold, above the capacitor energy threshold, or below the capacitor energy threshold; and

charging, by the control processor, the capacitor bank with the second electrical energy at least upon the determining that the electrical energy level of the capacitor bank is below the capacitor energy threshold.

7 . The method of claim 1 , wherein providing the first electrical energy to the first motor further comprises:

determining, by the control processor, an electrical energy level of the capacitor bank is at least one of: substantially the same as a capacitor energy threshold, above the capacitor energy threshold, or below the capacitor energy threshold; and

supplying, by the control processor, the first electrical energy to the first motor from the capacitor bank upon the determining that the electrical energy level of the capacitor bank is at least one of: substantially the same as the capacitor energy threshold, or above the capacitor energy threshold.

8 . The method of claim 1 , wherein providing the first electrical energy to the first motor further comprises:

determining, by the control processor, an electrical energy level of the capacitor bank is at least one of: substantially the same as a capacitor energy threshold, above the capacitor energy threshold, or below the capacitor energy threshold; and

supplying, by the control processor, the first electrical energy to the first motor from the battery module upon the determining that the electrical energy level of the capacitor bank is below the capacitor energy threshold.

9 . The method of claim 1 , wherein the pulser further comprises the control processor and a rotary pulser, wherein the supplying the first electrical energy to the first motor at least as the first motor is operating further comprises:

supplying the first electrical energy to the first motor at least as the first motor operates to generate one or more pressure pulses of the rotary pulser.

10 . The method of claim 9 , further comprising:

producing the one or more pressure pulses with the rotary pulser;

determining, by the control processor, one or more parameters of the one or more pressure pulses, wherein the one or more parameters including one or more of: an amplitude of the one or more pressure pulses, a duration of the one or more pressure pulses, a shape of the one or more pressure pulses, or a frequency of the one or more pressure pulses; and

interpreting, by the control processor, one or more characteristics of a drilling operation from the one or more parameters of the pressure pulses.

11 . A pulser configured to operate at a down hole location in a well bore, the pulser comprising:

a pulser assembly having a housing, at least one rotatable element in the housing, and at least one passage, wherein the at least one rotatable element is configured to rotate to inhibit fluid flowing through the at least one passage to generate a pressure pulse in the fluid;

one or more motors coupled to the at least one rotatable element and configured to cause the at least one rotatable element to rotate;

a capacitor bank electronically coupled to the one or more motors; and

a control processor electronically coupled to the one or more motors and the capacitor bank, the control processor configured to:

control operation of a first motor of the one or more motors to rotate the at least one rotatable element in order to generate a pressure pulse as fluid flows through the pulser assembly;

provide a first electrical energy to the first motor at least as the first motor operates;

receive a measurement of a determined position of the at least one rotatable element, wherein determined position of the at least one rotatable element is used to determine opening and closing of at least one switch to a battery module or a capacitor bank of the pulser;

receive a signal to stop the first motor;

stop the first motor so that the at least one rotatable element stops;

control receipt of a second electrical energy from the first motor at least as the first motor stops and the at least one rotatable element stops;

direct at least some of the second electrical energy to the capacitor bank.

12 . The pulser of claim 11 , wherein the first motor is a direct current (DC) motor.

13 . The pulser of claim 12 , wherein the second electrical energy is produced by the DC Motor as the DC Motor stops.

14 . The pulser of claim 12 , wherein the DC motor is at least one of: a brushless DC motor, an un-commutated DC motor, a permanent magnet DC motor, or a wound-stator DC motor.

15 . The pulser of claim 11 , wherein the control processor is further configured to:

determine that the received second electrical energy is at least one of: the same to a motor energy threshold, above the motor energy threshold, or below the motor energy threshold; and

switch the second electrical energy to the capacitor bank upon a determination that the received second electrical energy is at least one of: the same to the motor energy threshold, or above the motor energy threshold.

16 . The pulser of claim 15 , wherein the control processor is further configured to:

determine an electrical energy level of the capacitor bank is at least one of: the same to a capacitor energy threshold, above the capacitor energy threshold, or below the capacitor energy threshold; and

charge the capacitor bank with the second electrical energy at least upon a determination that the electrical energy level of the capacitor bank is below the capacitor energy threshold.

17 . The pulser of claim 11 , wherein the control processor is further configured to:

determine an electrical energy level of the capacitor bank is at least one of: the same to a capacitor energy threshold, above the capacitor energy threshold, or below the capacitor energy threshold; and

provide the first electrical energy to the first motor from the capacitor bank upon a determination that the electrical energy level of the capacitor bank is at least one of: the same to the capacitor energy threshold, or above the capacitor energy threshold.

18 . The pulser of claim 11 , further comprising a battery module, wherein the control processor is further configured to:

determine an electrical energy level of the capacitor bank is at least one of: the same to a capacitor energy threshold, above the capacitor energy threshold, or below the capacitor energy threshold; and

provide the first electrical energy to the first motor from the battery module upon a determination that the electrical energy level of the capacitor bank is below the capacitor energy threshold.

19 . The pulser of claim 11 , further comprising a rotary pulser, wherein the control processor is further configured to:

provide the first electrical energy to the first motor at least for operation of the first motor in one or more pulses of the rotary pulser.

20 . The pulser of claim 19 , wherein the rotary pulser configured to produce the one or more pulses in a drilling fluid, the control processor is configured to:

receive one or more pressure pulses produced by the rotary pulser;

determine one or more parameters of the one or more pressure pulses, the one or more parameters including one or more of: an amplitude of the one or more pressure pulses, a duration of the one or more pressure pulses, a shape of the one or more pressure pulses, or a frequency of the one or more pressure pulses; and

interpret one or more characteristics of a drilling operation from the one or more parameters of the pressure pulses.