20m New Rig Electrical System Design

With different work requirements in different fields,the demand for the structural performance of small drilling rigs is constantly increasing,and innovation breakthroughs in the field of small drilling rigs are increasingly important.Small rigs are widely used and indispensable in geological exploration and blasting holes,but automated drilling rigs have not yet been fully popularized.Small rigs on the market today are all rear-end motor constructions.This structure increases the load on the drill-drive motor and usually requires a high-power motor to provide power,which increases the overall power consumption of the rig,and the high-power motor is usually bulky.Larger weight is not convenient to carry.At present,most diesel and gasoline generators are used to power small rigs,using a large amount of non-renewable resources,and bring a series of environmental pollution problems.This paper takes a small portable drilling rig system as its application background,based on the joint development project of Chengdu University of Technology and Chuanqing Geophysical company join Development Project.“20m new electric drilling rig development”.It mainly develops a new type of pre-drilling rig with drilling depth of up to 20 m.The design of the structure is the main innovation of this topic.The new type of small drilling rig used a recyclable battery for energy supply,which eliminates the traditional diesel and gasoline generator model,reduced the consumption of non-renewable energy,and also solves the pollution problem during the use of drilling rigs.The main research content of this paper can be divided into the following aspects:1.Downhole drilling mechanism electrical system designThis design adopts the structure of the front motor,the motor power is smaller,the volume is smaller and the weight is lighter.The motor directly drives the drill to work,which reduced the load of the motor and also reduced the weight of the front motor system.By calculating the power required by the motor and the motor torque during the downhole drilling process,a brushless DC motor is selected by suitable parameters.Using PWM speed control technology and IGBT driving circuit to achieve motor speed and steering functions.The over-current protection device is designed by monitor the motor current.When the current is too large,the over-current fault indicator lights up.At the same time,the system generates a feedback signal to the SCM to stop the motor and protect the motor.2.Drill pipe lifting electrical system designDifficulty of the drill rod lifting system lies in the design of the mechanical structure.The electrical system includes three parts: lifting motor,driving module and control signal.The lifting motor is based on the total mass of the drill rod,and calculates the required pulling force and the drill rod lifting process.The power,finally combined with the torque formula and other detailed parameters are selected.In combination with the power requirements of the motor,the corresponding drive module was selected.A control signal is generated through the operating lever to control the positive and negative rotation of the motor so as to control the movement of the drill rod.3.mud circulation electrical system designThe mud circulation system designed to focus on the control of the mud flow.By controlling the PWM duty cycle in different gears,the motor speed can be controlled to regulate the flow of the mud pump.There are a total of five gears in the mud circulation system.4.electrical control system designThe control system is based on the C8051F020 microcontroller,and the corresponding control signals are implemented according to the specific requirements of each subsystem.Through the operation of the keys and the lever,you can control the signals output.The control circuit is connected with the drive circuit.The control signal output from the single-chip microcomputer controls the turn-on and turn-off of the diagonal drive components of the motor,so that each module motor can be operated according to the demand,thereby realizing the normal operation of the small-sized drilling machine.5.power system designAccording to the requirements of small-scale drilling rigs,a small drilling rig power system is designed by mainly complete power system power estimation,battery type selection and battery group selection.And according to the requirements of the power supply for the drill motor,drill rod lifting motor,mud circulating motor and the main control system in the small drilling rig system,the power distribution is performed.At present,preliminary testing of each module has been completed,which is basically consistent with the expected results.Downhole drilling mechanism test section,press the forward key,the oscilloscope shows that the motor rotates with a 20% duty cycle voltage,and then press the accelerator key continuously,the oscilloscope shows that the duty cycle continues to increase until it is added to the 10 th gear.The ratio is 100% waveform to display as a straight line.Press the deceleration button and the duty cycle decreases.At any speed,press the Invert button to switch the waveform.Press the Acceleration/Deceleration button in the reversed state.The duty cycle can be changed as required.When the duty cycle is set to 60%,the oscilloscope shows 59.9%.Although there is a certain error,this result can meet the design requirements.In the mud circulation system test section,square waves with different duty cycles can be obtained when different gear buttons are pressed,and the corresponding gear indicator light is on.The division of the gears in the design is to divide the entire cycle into 2 levels by 25% and one stage.This method of division is only a preliminary division and can be divided into more detailed in practical applications.