CPLD (Complex Programmable Logic Device)-based while-drilling mud pulser electromagnetic valve driving method

Abstract

The invention relates to the technical field of petroleum drilling, in particular to a while-drilling mud pulser solenoid valve driving method based on a CPLD (complex programmable logic device), which comprises the following steps: respectively determining PWM (pulse-width modulation) control parameters of a quick starting stage, a current adjusting stage and a pull-in keeping stage of a solenoid valve according to the depth of a well where a target solenoid valve is located; the CPLD driving module controls and outputs an initial starting voltage signal, controls and outputs a current driving waveform according to the PWM control parameter in the quick starting stage, controls and outputs the current driving waveform according to the PWM control parameter in the current adjusting stage, controls and outputs the current driving waveform according to the PWM control parameter in the pull-in maintaining stage, and lasts for a preset time; and electromagnetic valve driving of the while-drilling mud pulser is completed. The problems that when wireless measurement while drilling signals are transmitted in the prior art, due to the fact that the well depth is too large, the quality of electric signals for controlling an electromagnetic valve is affected, the electromagnetic valve cannot be effectively driven to be opened or closed, and mud positive pulse pressure waves are delayed and inaccurate are solved.

Description

Technical Field

[0001] The invention relates to the technical field of oil drilling, and in particular to a driving method of a while-drilling mud pulser solenoid valve based on CPLD. Background Art

[0002] Mud positive pulse pressure wave transmission is a widely used wireless measurement while drilling signal transmission method. However, its propagation speed is affected by factors such as mud properties, drill string size, and environmental parameters. The degree of signal attenuation is related to parameters such as drill string size, pulse frequency, mud parameters, and well depth. As the drilling depth increases, the transmission quality of the mud pressure signal is also affected by the performance of the pulser drive circuit. Among them, the solenoid valve is the actuator of the system, and its driving efficiency affects the pressure wave transmission. Therefore, a more efficient mud pulser solenoid valve drive system is needed. The existing solenoid valve control is controlled by PLD. The drive algorithm cannot be modified after solidification. When the depth of the construction well increases, the downhole pressure also increases. At this time, the energy of the driving solenoid valve is insufficient, causing the pulser mushroom head to move into place, affecting the transmission quality of the mud pressure wave, resulting in an increase in the bit error rate of the wireless while drilling ground decoding system, which is not conducive to the on-site construction of the wireless while drilling system. Summary of the invention

[0003] The present invention proposes a driving method for a while-drilling mud pulser solenoid valve based on CPLD, so as to solve the problem that in the past, when wireless while-drilling measurement signal transmission is performed, the quality of the electrical signal controlling the solenoid valve is affected due to the deep well depth, and the solenoid valve cannot be effectively driven to open or close, resulting in delay and inaccuracy of the mud positive pulse pressure wave.

[0004] According to one aspect of the present invention, a method for driving a solenoid valve of a mud pulser while drilling based on CPLD is provided, comprising: a CPLD driving module; The CPLD driving module is connected to the target solenoid valve via the power amplifier module and the MOSFET switch module; Obtain the well depth where the target solenoid valve is located; According to the well depth, respectively determining the PWM control parameters of the solenoid valve in the rapid start-up phase, the PWM control parameters in the current adjustment phase, and the PWM control parameters in the pull-in holding phase; The CPLD driving module controls the output of the initial starting voltage signal which is transmitted to the MOSFET switch module after passing through the power amplifier module to control the opening of the solenoid valve. After the first predetermined time, the CPLD driving module controls the output current driving waveform according to the PWM control parameters of the quick start stage. After the second predetermined time, the output current driving waveform is controlled according to the PWM control parameters of the current adjustment stage. After the third predetermined time, the output current driving waveform is controlled according to the PWM control parameters of the pull-in and hold stage, thereby completing the driving of the while-drilling mud pulser solenoid valve.

[0005] Preferably, the CPLD driving module comprises: an MCU, an anti-jitter logic circuit, a timer logic circuit, a PWM frequency setting logic circuit, a PWM duty cycle setting logic circuit and a PWM output logic circuit; The MCU is connected to the power amplifier module through the de-jitter logic circuit, and the control signal output by the MCU is transmitted to the power amplifier module after being de-jittered by the de-jitter logic circuit.

[0006] Preferably, the initial starting voltage signal is: The CPLD driving module controls the output bus voltage, which is transmitted to the MOSFET switch module after passing through the power amplifier module to control the opening of the solenoid valve.

[0007] Preferably, the method for determining the PWM control parameters of the solenoid valve in the rapid start-up phase according to the well depth includes: If the well depth is less than 4000m, the frequency in the PWM control parameters of the quick start phase is 18-25KHz, and the duty cycle is 75%; If the well depth is greater than 4000m, the frequency in the PWM control parameters of the quick start phase is 25-35KHz, and the duty cycle is 75-80%.

[0008] Preferably, the method for determining and adjusting the PWM control parameters in the current stage according to the well depth includes: If the well depth is below 4000m, the PWM control parameters of the current stage are adjusted as follows: frequency is 2.3-4.2KHz, duty cycle is 25%; If the well depth is greater than 4000m, the PWM control parameters of the current stage are adjusted to: frequency of 4-6KHz, duty cycle of 25-32%.

[0009] Preferably, the method for determining the PWM control parameters in the pull-in holding stage according to the well depth includes: If the well depth is below 4000m, the PWM control parameters in the pull-in holding stage are: frequency 6-12KHz, duty cycle 50%; If the well depth is greater than 4000m, the PWM control parameters in the pull-in and hold phase are: frequency is 12-18KHz, and duty cycle is 50-70%.

[0010] Preferably, the average voltage Ue in the PWM control parameters in the rapid startup phase, the PWM control parameters in the current adjustment phase, and the PWM control parameters in the pull-in and hold phase is: Ue=Udc*D; Where Udc is the bus voltage and D is the duty cycle; The average current I in the PWM control parameters of the fast start phase, the PWM control parameters of the current adjustment phase, and the PWM control parameters of the pull-in and hold phase is: I = Ue / R; In the formula, Ue is the average voltage and R is the equivalent resistance of the solenoid valve.

[0011] Preferably, the value range of the first predetermined time is: 30~50ms; The value range of the second predetermined time is: 150-220ms; The value range of the third predetermined time is: 7 to 10 ms.

[0012] The present invention has at least the following beneficial effects: The present invention proposes a driving method for a while-drilling mud pulser solenoid valve based on CPLD. The excellent parallel computing capability of CPLD is utilized in combination with the three-stage PWM control parameters of the driving solenoid valve to enhance the driving signal strength of the mud pressure wave and reduce the transmission delay of the mud pressure wave, thereby achieving efficient driving of the mud pulser solenoid valve and improving the data decoding rate of the wireless while-drilling ground decoding system. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The accompanying drawings herein are incorporated into and constitute a part of the specification. These drawings illustrate embodiments consistent with the present invention and, together with the specification, are used to explain the technical solutions of the present invention.

[0014] Figure 1 A device connection block diagram of a method for driving a solenoid valve of a mud pulser while drilling based on CPLD according to an embodiment of the present invention is shown; Figure 2 A control principle diagram of a solenoid valve driving method for a mud pulser while drilling based on CPLD according to an embodiment of the present invention is shown. Implementation

[0015] Various exemplary embodiments, features and aspects of the present invention will be described in detail below with reference to the accompanying drawings. The same reference numerals in the accompanying drawings represent elements with the same or similar functions. Although various aspects of the embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless otherwise specified.

[0016] The word “exemplary” is used exclusively herein to mean “serving as an example, example, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments.

[0017] The term "and / or" herein is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the term "at least one" herein represents any combination of at least two of any one or more of a plurality of. For example, including at least one of A, B, and C can represent including any one or more elements selected from the set consisting of A, B, and C.

[0018] In addition, in order to better illustrate the present invention, numerous specific details are provided in the following specific embodiments. It should be understood by those skilled in the art that the present invention can be implemented without certain specific details. In some examples, methods, means, components and circuits well known to those skilled in the art are not described in detail in order to highlight the subject matter of the present invention.

[0019] Figure 1 A device connection block diagram of a method for driving a solenoid valve of a mud pulser while drilling based on CPLD according to an embodiment of the present invention is shown; Figure 2 FIG. 2 is a control schematic diagram of a CPLD-based electromagnetic valve driving method for a mud pulser while drilling according to an embodiment of the present invention. Figure 1-2 As shown, a method for driving a solenoid valve of a mud pulser while drilling based on CPLD includes: a CPLD driving module; the CPLD driving module is connected to a target solenoid valve through a power amplifier module and a MOSFET switch module; step S01: obtaining the well depth of the target solenoid valve; step S02: determining the PWM control parameters of the rapid start-up phase, the PWM control parameters of the current adjustment phase, and the PWM control parameters of the pull-in and hold phase of the solenoid valve according to the well depth; step S03: the CPLD driving module controls the output of an initial starting voltage signal, which is transmitted to the MOSFET switch module after passing through the power amplifier module to control the opening of the solenoid valve; after a first predetermined time, the CPLD driving module controls the output current drive waveform according to the PWM control parameters of the rapid start-up phase; after a second predetermined time, the CPLD driving module controls the output current drive waveform according to the PWM control parameters of the current adjustment phase; after a third predetermined time, the CPLD driving module controls the output current drive waveform according to the PWM control parameters of the pull-in and hold phase, thereby completing the driving of the solenoid valve of the mud pulser while drilling.

[0020] In an embodiment of the present invention, the mud pulser solenoid valve driving system includes a CPLD (complex programmable logic device) driving module, a power amplifier module and a MOSFET (metal oxide semiconductor field effect transistor) switch module, wherein the CPLD driving module, the power amplifier module and the MOSFET switch module are respectively connected to a switching power supply module, so as to supply power to the entire control driving solenoid valve circuit. The switching power supply module provides a 5VDC power supply voltage for the CPLD driving module and a 14VDC rated working voltage for the power amplifier module.

[0021] Compared with PLD (Programmable Logic Device), CPLD has better parallel computing capability and low-latency propagation characteristics of IO ports, which can reduce the delay of signal transmission and realize complex logic functions. The digital drive signal output by CPLD control needs to be converted into a power drive signal to control the solenoid valve through the power amplifier module. This signal can realize the rapid switching of the solenoid valve and the charging and discharging control of the energy storage capacitor through the MOSFET switch module.

[0022] The CPLD-based solenoid valve driving method for a mud pulser while drilling provided by an embodiment of the present invention specifically comprises the following steps: Step S01: Obtain the well depth where the target solenoid valve is located.

[0023] In the embodiment of the present invention, the design of the frequency and duty cycle of the PWM (pulse width modulation) waveform is related to the well depth of the pulser construction. In order to improve the adaptability of on-site construction and realize the smooth driving and control of the solenoid valve, it is necessary to adjust the frequency and duty cycle of the PWM according to the well depth of the solenoid valve to be driven.

[0024] In the present invention, the CPLD driving module includes: an MCU, a de-jitter logic circuit, a timer logic circuit, a PWM frequency setting logic circuit, a PWM duty cycle setting logic circuit and a PWM output logic circuit; the MCU is connected to the power amplifier module through the de-jitter logic circuit, and the control signal output by the MCU is transmitted to the power amplifier module after being de-jittered by the de-jitter logic circuit.

[0025] In the embodiment of the present invention, as the bottom depth of the directional well and horizontal well construction increases and the ambient temperature gradually rises, the inductance and capacitance mismatch of the switch power supply module of the drilling while drilling system will introduce electrical noise, resulting in an increased probability of system false triggering. In order to avoid false triggering of the pulser solenoid valve drive, a multi-level debouncing processing of the debouncing logic circuit can be used. At the same time, the increase in the load of the wireless drilling instrument can also increase the electrical noise of the circuit system. When the instrument construction temperature is less than 125°C and the system power consumption is less than 100 watts, the debouncing logic circuit needs to be designed as a three-level debouncing for processing, which can eliminate most false triggers; when the instrument construction temperature is greater than 125°C and the system power consumption is between 100 and 300 watts, the debouncing logic circuit needs to be designed as a five-level debouncing to meet the on-site construction requirements. In theory, the more levels of debouncing logic circuit design, the better the debouncing effect, but the hardware resource consumption of CPLD and the changes in the use environment of the drilling instrument should be considered to design a reasonable multi-level debouncing logic circuit.

[0026] The timer logic circuit is used to set the duration and interval time of the control signal when outputting under PWM control; the PWM frequency setting logic circuit is used to set the frequency of the PWM output signal; and the PWM duty cycle setting logic circuit is used to set the duty cycle of the PWM output signal.

[0027] Step S02: According to the well depth, respectively determine the PWM control parameters of the solenoid valve in the rapid start-up phase, the PWM control parameters in the current adjustment phase, and the PWM control parameters in the pull-in and hold phase.

[0028] Step S03: The CPLD driver module controls the output of the initial startup voltage signal, which is transmitted to the MOSFET switch module after passing through the power amplifier module to control the opening of the solenoid valve. After the first predetermined time, the CPLD driver module controls the output current drive waveform according to the PWM control parameters of the quick startup stage. After the second predetermined time, the output current drive waveform is controlled according to the PWM control parameters of the current adjustment stage. After the third predetermined time, the output current drive waveform is controlled according to the PWM control parameters of the pull-in and hold stage, thereby completing the driving of the while-drilling mud pulser solenoid valve.

[0029] In the present invention, the value range of the first predetermined time is: 30~50ms; the value range of the second predetermined time is: 150~220ms; the value range of the third predetermined time is: 7~10ms.

[0030] In the present invention, the initial startup voltage signal is: the CPLD driving module controls the output bus voltage, which is transmitted to the MOSFET switch module after passing through the power amplifier module to control the solenoid valve to open.

[0031] In the embodiment of the present invention, the initial start is the solenoid valve opening stage, which requires the pulser solenoid valve mushroom head to move upward for a certain distance, at which time the power consumption required for driving the solenoid valve is the largest. The value of the first predetermined time is: 34ms.

[0032] The MCU sets the timing duration of the initial starting voltage signal to 34ms through the timer logic circuit; the MCU controls the output maximum drive current through the power amplifier module, that is, controls the output bus voltage 36V electrical signal to be transmitted to the MOSFET switch module to drive the solenoid valve to open; the DC voltage drive control of the solenoid valve starting section is realized in the initial startup phase; after the first predetermined time, that is, 34ms, the MCU controls the output current drive waveform according to the PWM control parameters of the quick startup phase.

[0033] In the present invention, the method for determining the PWM control parameters of the rapid start-up phase of the solenoid valve according to the well depth includes: if the well depth is less than 4000m, the frequency of the PWM control parameters in the rapid start-up phase is 18-25KHz, and the duty cycle is 75%; if the well depth is greater than 4000m, the frequency of the PWM control parameters in the rapid start-up phase is 25-35KHz, and the duty cycle is 75-80%.

[0034] In the embodiment of the present invention, after completing the initial startup, the MCU controls the output current driving square wave waveform according to the PWM control parameters in the fast startup phase; wherein the value of the second predetermined time is: 166ms.

[0035] If the depth of the well where the solenoid valve is located is less than 4000m, the MCU sets the output frequency to 21KHz through the PWM frequency setting logic circuit, and sets the output duty cycle to 75% through the PWM duty cycle setting logic circuit. After the setting is completed, the MCU controls the output frequency of 21KHz and the duty cycle of 75% through the PWM output logic circuit, which is converted into a power drive signal by the power amplifier module and then transmitted to the MOS switch module; the high-frequency PWM drive control of the solenoid valve drive is realized in the fast start-up stage. The drive current in this process is relatively large, which can ensure that the solenoid valve quickly completes the pull-in action; after the second predetermined time, that is, 166ms, the MCU controls the output current drive waveform according to the PWM control parameters of the current adjustment stage.

[0036] The design of the frequency and duty cycle of the PWM waveform in the fast start-up stage is related to the well depth of the pulser construction. In order to improve the adaptability of on-site construction, if the solenoid valve is located at a well depth of 4000-6000m, the frequency is adjusted to 28KHz and the duty cycle is adjusted to 80%, thereby ensuring that the pulser solenoid valve can be quickly and effectively attracted, and the pulser upload pressure wave is stable and reliable.

[0037] In the present invention, the method for determining the PWM control parameters of the current stage according to the well depth includes: if the well depth is less than 4000m, the PWM control parameters of the current stage are adjusted to: frequency of 2.3-4.2KHz, duty cycle of 25%; if the well depth is greater than 4000m, the PWM control parameters of the current stage are adjusted to: frequency of 4-6KHz, duty cycle of 25-32%.

[0038] In the embodiment of the present invention, after completing the quick startup, the MCU controls the output current driving square wave waveform according to the PWM control parameters of the current adjustment stage; wherein the value of the third predetermined time is: 7ms.

[0039] If the depth of the well where the solenoid valve is located is less than 4000m, the MCU sets the output frequency to 3.8KHz through the PWM frequency setting logic circuit, and sets the output duty cycle to 25% through the PWM duty cycle setting logic circuit. After the setting is completed, the MCU controls the output frequency of 3.8KHz and the duty cycle of 25% through the PWM output logic circuit, which is converted into a power drive signal by the power amplifier module and then transmitted to the MOSFET switch module; the low-frequency PWM control of the solenoid valve drive is realized in the current adjustment stage, which can quickly reduce the current driving the solenoid valve and start to use a small current to drive the solenoid valve; after the third predetermined time, that is, 7ms, the MCU controls the output current drive waveform according to the PWM control parameters of the pull-in holding stage.

[0040] When the inductive load of the solenoid valve passes high-frequency alternating current, an induced electromotive force V(t) = L*di / dt is generated, where L is the inductance and di / dt is the unit current change rate. The inductive load causes the current change to have a lag. In order to quickly reduce the solenoid valve drive current, the current adjustment stage undergoes a 7-10ms PWM wave control, and the frequency and duty cycle are reduced at the same time, the frequency is reduced to 2.3-4.2KHz, and the duty cycle is reduced to 25%. The PWM drive waveform with this design parameter can quickly reduce the solenoid valve drive current and maintain the solenoid valve in a stable closed state, which is suitable for well depths within 4000m. If the well depth is between 4000 and 6000m, the frequency is adjusted to 5KHz and the duty cycle is adjusted to 28% to avoid failure of the solenoid valve drive.

[0041] In the present invention, the method for determining the PWM control parameters of the pull-in and holding stage according to the well depth includes: if the well depth is less than 4000m, the PWM control parameters of the pull-in and holding stage are: frequency of 6 to 12KHz, and duty cycle of 50%; if the well depth is greater than 4000m, the PWM control parameters of the pull-in and holding stage are: frequency of 12 to 18KHz, and duty cycle of 50 to 70%.

[0042] In the embodiment of the present invention, after the current is adjusted, the MCU controls the output current to drive the square wave waveform according to the PWM control parameters in the pull-in holding stage.

[0043] If the depth of the solenoid valve is less than 4000m, the MCU sets the output frequency to 6.8KHz through the PWM frequency setting logic circuit, and sets the output duty cycle to 50% through the PWM duty cycle setting logic circuit. After the setting is completed, the MCU controls the output frequency to 6.8KHz and the duty cycle to 50% through the PWM output logic circuit, and transmits the control signal to the MOS switch module after being converted into a power drive signal by the power amplifier module. In the process of solenoid valve closing and holding, in order to minimize the power consumption of the wireless drilling system, the minimum holding current in the drive circuit needs to be designed; the holding current in the closing and holding stage is directly related to the construction well depth, and the output drive current should be able to keep the solenoid valve reliably closed, which is suitable for the construction requirements of pulser solenoid valves with a well depth of less than 4000m; if the well depth is between 4000 and 6000m, the frequency needs to be adjusted to 15KHz and the duty cycle needs to be adjusted to 60%, so that the pulse pressure wave transmission during actual construction on site is stable and reliable, and the ground mud pressure wave system decoding rate reaches 100%.

[0044] In the present invention, the average voltage Ue in the PWM control parameters of the rapid start-up phase, the PWM control parameters of the current adjustment phase, and the PWM control parameters of the pull-in and hold phase is: Ue=Udc*D (1); Where Udc is the bus voltage and D is the duty cycle; The average current I in the PWM control parameters of the fast start phase, the PWM control parameters of the current adjustment phase, and the PWM control parameters of the pull-in and hold phase is: I = Ue / R (2); In the formula, Ue is the average voltage and R is the equivalent resistance of the solenoid valve.

[0045] In the embodiment of the present invention, if the bus voltage is 36 V, the duty cycle in the PWM control parameters of each stage is substituted into formula (1) to calculate the average voltage Ue=27 V in the PWM control parameters of the fast start stage, the average voltage Ue=9 V in the PWM control parameters of the current adjustment stage, and the average voltage Ue=18 V in the PWM control parameters of the pull-in holding stage.

[0046] Substituting the average voltage Ue and the equivalent resistance R of the solenoid valve into formula (2) can calculate the average current in each stage. The MCU monitors the voltage and current when driving the solenoid valve in each stage through the obtained average voltage and average current to prevent the solenoid valve from being unable to reliably close due to the voltage and current not reaching or exceeding the average value.

[0047] like Figure 2 As shown, the CPLD driver module is designed with Altera's MAXⅡ series EPM240 chip, which is characterized by low power consumption and low propagation delay. The driver is turned on by the MCU signal, the system clock provides the time reference for the entire system, and the reset signal monitors the restart of the circuit; the purpose of debouncing (debouncing logic circuit) is to eliminate the driver's false triggering. If the signal is still high after debouncing, the solenoid valve DC voltage drive is turned on. The timer logic circuit includes three timers, namely timer1, timer2, and timer3, which are used to set the first predetermined time, the second predetermined time, and the third predetermined time respectively. Timer1, timer2, and timer start counting. When timer1 overflows, the DC voltage drive is turned off and the high-frequency PWM drive is started; when timer2 overflows, the high-frequency PWM drive is turned off and the low-frequency PWM drive is started; when timer3 overflows, the low-frequency PWM drive is turned off and the medium-frequency PWM drive is turned on, and it continues until the MCU signal becomes low level, ending the solenoid valve drive.

[0048] The present invention takes the CPLD driving module as the core, and the switching power supply module is responsible for providing continuous power to the circuit system. The digital driving signal output by the CPLD control needs to pass through the power amplifier module and be converted into a power driving signal. This signal controls the switch of the solenoid valve through the MOSFET switch module.

[0049] When the MCU issues a command to open the solenoid valve, the drive system opens the bus power supply circuit. At the same time, the energy storage capacitor of the power supply circuit accelerates the current rise rate of the solenoid valve. The solenoid valve armature begins to move under the electromagnetic drive. To speed up the pull-in speed, the initial starting voltage uses the bus voltage of 36V and lasts for 34ms. In order to reduce the system power consumption, the solenoid valve drive is switched to PWM control mode to make the solenoid valve armature fully pull-in. In order to further reduce power consumption, the frequency and duty cycle of the PWM square wave are adjusted to maintain the pull-in state of the solenoid valve with a lower current. This driving method can not only ensure the rapid and accurate opening and closing of the solenoid valve, but also greatly reduce the power consumption of the drive system.

[0050] The principle of the solenoid valve driving method of the drilling mud pulser based on CPLD is to realize the high-speed and accurate switching of the solenoid valve, and at the same time have good reliability, low power consumption and strong adaptability. The PWM pulse width modulation method is adopted, the bus voltage and the withstand voltage capacitor structure are directly taken, and the pulse width debugging structure is combined with the current feedback, which can accurately adjust the solenoid valve current, with low power consumption and high stability.

[0051] When the present invention is conducting a drilling operation on the horizontal well site of the Su 53 block in the Sulige area, the mud pulser solenoid valve driving method is experimentally applied to the rotary steerable drilling system. When the well is drilled to a depth of 4020 m, the mud pressure signal is significantly enhanced compared with the adjacent wells, thereby improving the decoding rate of the mud pressure signal of the wireless while drilling ground decoding system.

[0052] It can be understood that the above-mentioned various method embodiments mentioned in the present invention can be combined with each other to form a combined embodiment without violating the principle logic. Due to space limitations, the present invention will not go into details.

[0053] The execution subject of the CPLD-based while drilling mud pulser solenoid valve driving method may be a CPLD-based while drilling mud pulser solenoid valve driving device, for example, the CPLD-based while drilling mud pulser solenoid valve driving method may be executed by a terminal device or a server or other processing device, wherein the terminal device may be a user equipment (UE), a mobile device, a user terminal, a terminal, a cellular phone, a cordless phone, a personal digital assistant (PDA), a handheld device, a computing device, a vehicle-mounted device, a wearable device, etc. In some possible implementations, the CPLD-based while drilling mud pulser solenoid valve driving method may be implemented by a processor calling a computer-readable instruction stored in a memory.

[0054] Those skilled in the art will appreciate that, in the above method of specific implementation, the order in which the steps are written does not imply a strict execution order and does not constitute any limitation on the implementation process. The specific execution order of the steps should be determined by their functions and possible internal logic.

[0055] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or technical improvements in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A method for driving a solenoid valve of a drilling mud pulser based on CPLD, characterized in that: include: CPLD driver module; The CPLD driving module is connected to the target solenoid valve via the power amplifier module and the MOSFET switch module; Obtain the well depth where the target solenoid valve is located; According to the well depth, respectively determining the PWM control parameters of the solenoid valve in the rapid start-up phase, the PWM control parameters in the current adjustment phase, and the PWM control parameters in the pull-in holding phase; The CPLD driving module controls the output of the initial starting voltage signal which is transmitted to the MOSFET switch module after passing through the power amplifier module to control the opening of the solenoid valve. After the first predetermined time, the CPLD driving module controls the output current driving waveform according to the PWM control parameters of the quick start stage. After the second predetermined time, the output current driving waveform is controlled according to the PWM control parameters of the current adjustment stage. After the third predetermined time, the output current driving waveform is controlled according to the PWM control parameters of the pull-in and hold stage, thereby completing the driving of the while-drilling mud pulser solenoid valve.

2. The CPLD-based while-drilling mud pulser solenoid valve driving method according to claim 1, characterized in that: The CPLD driving module includes: an MCU, a de-jittering logic circuit, a timer logic circuit, a PWM frequency setting logic circuit, a PWM duty cycle setting logic circuit, and a PWM output logic circuit; The MCU is connected to the power amplifier module through the de-jitter logic circuit, and the control signal output by the MCU is transmitted to the power amplifier module after being de-jittered by the de-jitter logic circuit.

3. The CPLD-based while-drilling mud pulser solenoid valve driving method according to claim 1, characterized in that: The initial starting voltage signal is: The CPLD driving module controls the output bus voltage, which is transmitted to the MOSFET switch module after passing through the power amplifier module to control the opening of the solenoid valve.

4. The CPLD-based while-drilling mud pulser solenoid valve driving method according to claim 1, characterized in that: The method for determining the PWM control parameters of the solenoid valve in the rapid start-up phase according to the well depth includes: If the well depth is less than 4000m, the frequency in the PWM control parameters of the quick start phase is 18-25KHz, and the duty cycle is 75%; If the well depth is greater than 4000m, the frequency in the PWM control parameters of the quick start phase is 25-35KHz, and the duty cycle is 75-80%.

5. The CPLD-based while-drilling mud pulser solenoid valve driving method according to claim 1, characterized in that: The method for determining and adjusting the PWM control parameters in the current stage according to the well depth includes: If the well depth is below 4000m, the PWM control parameters of the current stage are adjusted as follows: frequency is 2.3-4.2KHz, duty cycle is 25%; If the well depth is greater than 4000m, the PWM control parameters of the current stage are adjusted to: frequency of 4-6KHz and duty cycle of 25-32%.

6. The CPLD-based while-drilling mud pulser solenoid valve driving method according to claim 1, characterized in that: The method for determining the PWM control parameters in the pull-in holding stage according to the well depth includes: If the well depth is below 4000m, the PWM control parameters in the pull-in holding stage are: frequency 6-12KHz, duty cycle 50%; If the well depth is greater than 4000m, the PWM control parameters in the pull-in and hold phase are: frequency is 12-18KHz, and duty cycle is 50-70%.

7. The CPLD-based method for driving a solenoid valve of a mud pulser while drilling according to any one of claims 4 to 6, characterized in that: The average voltage Ue in the PWM control parameters of the fast start phase, the PWM control parameters of the current adjustment phase, and the PWM control parameters of the pull-in and hold phase is: Ue=Udc*D; Where Udc is the bus voltage and D is the duty cycle; The average current I in the PWM control parameters of the fast start phase, the PWM control parameters of the current adjustment phase, and the PWM control parameters of the pull-in and hold phase is: I = Ue / R; In the formula, Ue is the average voltage and R is the equivalent resistance of the solenoid valve.

8. The CPLD-based method for driving a solenoid valve of a mud pulser while drilling according to any one of claims 1 to 6, characterized in that: The value range of the first predetermined time is: 30~50ms; The value range of the second predetermined time is: 150-220ms; The value range of the third predetermined time is: 7-10ms.

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