RU4188U1 - DEVICE FOR REGULATING THE ROTATION FREQUENCY AND THE MOMENT OF THE ELECTRIC DRIVE - Google Patents

Abstract

1. A device for controlling the number of revolutions and the moment of the electric drive, comprising a bit load adjuster, a current sensor and a speed sensor, characterized in that it is equipped with a microprocessor kit that performs the functions of regulating the axial load on the bit, the speed and current of the electric drive, its inputs are connected to a bit load adjuster, a current sensor and a speed sensor, and a converter supplying the bit feed regulator motor is connected to its output, and the microprocessor set is made with the possibility of the implementation of the algorithm for the program for regulating the axial load on the bit in the bit feed regulator, the algorithm for determining the static current of the engine and the algorithm for calculating the control action in the subroutine for regulating the axial load on the bit. 2. The device according to claim 1, characterized in that it is equipped with a weight sensor connected to the input of the microprocessor kit.

Description

DEVICE FOR REGULATING THE NUMBER OF SPEEDS AND MOMENT OF THE ELECTRIC DRIVE

Useful mod, spruce refers to electrical engineering, namely to devices for regulating engines.

A device for controlling the number of revolutions and the moment of an electric drive is known, comprising a bit load adjuster, a current sensor, a speed sensor and a weight sensor 1.

The disadvantage of the device is, secondly, its low reliability due to the presence of a weight sensor at the fixed end of the hoist rope of the bit feed regulator, the need to remove the weight sensor when replacing the rope and frequent bypasses and the subsequent calibration of measuring devices create operational inconvenience, and secondly, the ambiguity readings of the weight sensor on the fixed end of the hoist rope and the same effort on the hook for lifting and feeding modes (for example, when switching from feeding to lifting, the weight sensor shows less weight, and when moving from lift to feed, it is greater), which arises due to the presence of friction forces in the system, is equivalent to a positive feedback signal, which can lead in some cases to unstable operation of the bit feed regulator and self-oscillations at low drilling speeds; thirdly, the low accuracy of the measurements of the weight sensor due to the presence of friction in the system, which causes a decrease in the accuracy of maintaining a given load on the bit.

A device for controlling the speed and torque of an electric drive is known, comprising a bit load adjuster, a current sensor and a speed sensor. The device also contains a current controller, a speed controller, a weight controller and a static current sensor 2. The bit load controller is connected to the input of the weight controller, the second input of which is connected to the output of the weight sensor, and the first input of the speed controller, the second input of which is connected to the output of the weight controller connected to a speed sensor; the current controller is connected by one of the inputs to the output of the speed controller, and its second input is connected to the output of the current sensor. A converter is connected to the output of the current regulator, feeding the motor of the bit feed regulator.

MKI Kji.HQIPl / OO

a significant difference in the time constants of the electromagnetic and mechanical links of the electric drive, since an increase in the coefficient in the forcing part of the weight regulator, which regulates according to the proportional-integral law, which could improve the indicator in question, leads to a significant deterioration in electromagnetic transients; secondly, the low speed of the electric drive in response to the disturbing effect due to the significant difference in the time constants of the electromagnetic and mechanical links of the electric drive, since an increase in the coefficient in the boosting part of the weight regulator, which could improve the indicator under consideration, leads to a significant deterioration in electromagnetic transients; thirdly, additional wear of drill pipe string elements due to the oscillatory nature of the processes during disturbances along the load channel when the weight regulator setting is applied; fourthly, significant overloads of the bit, leading to a decrease in its wear resistance, and significant underloads, which reduce the productivity of drilling operations arising from the inevitable delay with which the electric drive responds to the application of load, since in a system with distributed parameters, the electric drive of the bit feed regulator is tackle system - drill pipe string (electromechanical system) a device for controlling the speed and torque of an electric drive not only with delay perceives information Much about the change in load, but also affects the working tool through the finite time of the signal through the pipes.

Due to these shortcomings, the bit during operation experiences significant mechanical overloads and quickly wears out. The need for frequent change of the bit and the implementation of appropriate hoisting operations reduces the productivity of drilling operations. Working in hard layers, with an additional increase in the hardness of the rock and, consequently, a dynamic increase in the load on the bit, the rock cutting tool not only experiences overloads, but also crushes the drillable rock, which negatively affects drilling efficiency.

The technical result, which the utility model aims to achieve, is to improve the quality of regulation of the electric drive due to the formation of dynamic characteristics of the electric drive that provide optimal conditions for working out the rock cutting tool due to a decrease in the dynamic error of regulation and an increase in the speed of the system, as well as an increase in the productivity of drilling operations.

The specified result is achieved in that the device for controlling the number of revolutions and the moment of the electric drive, comprising a bit load adjuster, a current sensor and a speed sensor, is equipped with a microprocessor kit that performs the functions of regulating the axial load on the bit, the number of revolutions and current of the electric motor; the inputs of this set are connected to a bit load controller, a current sensor and a speed sensor, to the output of which a converter feeding the motor is connected, while the microprocessor set is configured to implement an algorithm for controlling the axial load on the bit in the bit feed regulator, an algorithm for determining the static motor current and algorithm for calculating the control action in the subroutine for regulating the axial load on the bit. For additional control of the axial load on the bit, this device can be equipped with a weight sensor connected to the input of the microprocessor kit.

The utility model is illustrated by drawings, in which: in Fig. 1 is a functional diagram of a device for controlling the number of revolutions and the moment of electric drive of the bit feed regulator, in Fig. 2 is an algorithm for the program for regulating the axial load on a bit in the bit feed regulator, in Fig. 3 is a flow chart of the subroutine Definition static current of the engine, in figure 4 is an algorithm for calculating the control action in the subroutine for regulating the axial load on the bit.

A device for controlling the number of revolutions and the moment of electric drive of the bit feed controller comprises a bit load adjuster 1, a current sensor 2, a speed sensor 3 and a microprocessor set 4 (Fig. 1). Input 1 of the microprocessor set 4 is connected to the setpoint 1 of the load on the bit, input 2 is connected to a current sensor 2, and input 3 is a speed sensor 3. To the output of the microprocessor set 4, a converter 5 is connected, a power supply motor 6 of the electric drive.

The microprocessor kit performs the functions of regulating the axial load on the bit, speed and engine torque. As a microprocessor kit, a microprocessor kit can be used, for example, MK-51 3. A device for controlling the speed and torque of an electric drive can be used to regulate the feed bit with a motor of both direct and alternating current.

A device for controlling the number of revolutions and the moment of electric drive of the bit feed regulator works as follows. When changing the load on the bit (not shown in the figure) due to changes in the hardness of the drilled rock, the feed rate (engine speed 6) and the current of the engine 6 also change. Information about the change in the last two parameters is transmitted to the microprocessor set 4 through, respectively, the speed sensor 3 and current sensor 2. Information about the current value of the load on the bit is calculated programmatically by a signal from the current sensor 2. So, with an increase in the load on the bit, the signal from the current sensor 2 will decrease on average. Using this calculated value, the microprocessor set 4 determines the fact of an increase in the load and, according to the algorithm laid down in it (see Fig. 2), generates and issues to the converter 5, which feeds the engine 6, such a control action that brings the load on the bit in accordance with that set on the control unit 1 load per bit value. In this case, the signal from the current sensor 2 increases, and the signal from the speed sensor 3 decreases. The control process is completed in the case when the value of the focus on the bit calculated by the microprocessor set 4 through the signal from the current sensor 2 coincides with the accuracy required by the control conditions with the signal from the bit load adjuster I. When the load on the bit is reduced due to any disturbance, the change in the signals from the current sensor 2 and the speed sensor 3 is opposite to that described previously.

Below, the operation of the device for controlling the number of revolutions and the moment of electric drive of the bit feed regulator is described in more detail. The program for regulating the axial load on the bit, embedded in the microprocessor set 4, includes a subroutine Determination of the static current of the engine, a subroutine for regulating the axial load on the bit, a subroutine for controlling the engine speed and a subroutine for regulating the motor current. When the device is turned on, the axial load control program for the bit initializes the variables used by it. Pa setpoint 1 load on the bit is set (technologically optimal) value of the load on the bit. The drill pipe string (not shown in the figure) disengages and moves toward the bottom. At the same time, in the subroutine (see Fig. C) the determination of the static current is calculated and the microprocessor set 4 remembers the total weight of the column until it contacts the face. This value is used when calculating the load on the bit. The axial load on the bit is the difference between the total weight of the column in contact with the bottom and the force on the hook. Therefore, to determine the current value of the axial load, the current weight value calculated by the nodprofamma is subtracted. Determination of the static current from the fixed value of the total weight of the drill pipe string until it faces the bottom (see figure 2).

When the bit touches the face (not shown in the figure), as well as when the hardness of the drilled rock increases, the weight on the hook will begin to decrease, and the load on the bit will increase, which is determined by the above path (see figure 2). In this case, the number of revolutions of the engine 6 during feeding is reduced until the load on the bit reaches a value close to the specified one and a drilling mode is established at which the bit feed rate is equal to the drilling speed. This is achieved by the fact that the axial load error, calculated as the sum of the current value of the load on the bit with the digitized and inverted reference signal, is positive when the load increases. In accordance with this error, the subroutine for controlling the axial load on the bit (see Fig. 2), according to the algorithm described below (Fig. 4), generates a control action.

This corrective action, minus the feedback signal from the number of revolutions of the engine 6, measured by the speed sensor 3 and converted to digital form, determines the error signal according to the feed rate (i.e., during descent) of the drill pipe string. If the load on the bit exceeds the set value, this signal will be positive, and equilibrium will be achieved when the changing signal at the output of the speed sensor 3 coincides with the value of the speed signal specified by the axial load on the bit subroutine. The calculated error is worked out by the engine speed control subroutine (RRPD) shown in FIG. 2. The control action generated by this subroutine can be calculated using proportional (P), proportional-integral (PI) or proportionally-integral-differential (PID) control algorithms 4.

When the current (or torque) of the electric motor 6 changes, the signal at the output of the current sensor 2 changes, moreover, if this signal is only positive when the system is in steady state, then it can change its sign in the dynamics (when using the inverter 5). Measured by the current sensor 2 and digitized the current value of the current (or torque) of the motor 6, being subtracted from the control action generated by the subroutine for controlling the speed of the electric motor (see figure 2), will give the error

current, which when the load on the bit exceeds the specified value will be positive, and in the steady state of the electromechanical system is zero. In accordance with this error, the subroutine for regulating the current (or torque) of the motor 6 (PRTD), shown in FIG. 2, calculates the control action in the microprocessor set 4 using P, PI, or PID control laws, which, after issuing it to the input port, the output of the microprocessor set 4, is fed to the input of the converter 5 (if the pulse-phase control system of the converter is not digital, then this signal must be converted to analog form).

Since when the load on the bit exceeds the set value, the control action supplied from the output of the microprocessor set 4 to the input of the converter 5 has a positive sign, it leads to an increase in the torque of the engine 6 and, accordingly, to slowdown of the lower string (lowering the speed of lowering the drill pipe string) . If there is a sharp increase in the hardness of the rock being drilled, then the torque of the engine 6 may even exceed the load moment, which is determined to a large extent by the weight of the column, which will lead to a brief rise in the bit, preventing an excessive increase in the load on the bit.

When the bit gets from hard rock to softer at the first moment of time, the bit load slightly decreases, and under the influence of the controlled action from the microprocessor set 4, the bit feed rate will increase to such a value that the drilling mode is established with a higher speed at a bit load close to to the specified one, which will be provided by changing the error signs worked out by the axial load control subroutine for the bit, the engine speed control subroutine and the subroutines second motor current control (see FIG. 2).

As already noted, the weight of the drill pipe string is determined by the static current determination routine (see FIG. 3), which operates according to the following algorithm. The fact is used that the weight of the column corresponds quite accurately to the tension of the running branch of the hoist rope (not shown in the figure) proportional to the static current (torque) of the electric motor 6. The current value of the current of the motor 6, measured by the current sensor 2, is converted to digital form. Since this signal can still contain interference, before differentiation, it is processed in microprocessor set 4 according to one of the digital algorithms

filtering 5 or smoothed 6. For this purpose, it is also possible to install an RC filter at the output of the current sensor 2 (not shown in Fig.). The differentiated and filtered signal is multiplied by a coefficient proportional to the moment of inertia of the engine. The calculated value of the dynamic current is subtracted from the current value of the current and thus determines the static current of the motor 6, corresponding to the current weight of the column on the hook.

I control its effect in the subroutine for regulating the axial load on the bit is calculated by the following algorithm (see figure 4). The values of the signal for setting the speed of the Ozs, the amplitude of the control action USHM, the counter Yds of the discrete time intervals and the counter I of the points at which correction is introduced during the transient processes, while the number of control points is N, are initialized when the microprocessor set 4 is turned on as follows: U ;, c -O, and: shm 0.1 1, Yds Tim / AT, where

Tim is the time of linear rise of the speed reference signal by the magnitude of the amplitude of the control action calculated by this subprogram;

DT - discreteness in time with which the microprocessor kit works.

If the counter Mdc of the discrete time intervals and the counter 1 of the correction points correspond to the initialized values and there is an error in the load on the bit that exceeds the permissible error in the subroutine, the value of this error at time moment k is stored by microprocessor set 4 as 5aach. If the error does not exceed the specified value, the value of the reference signal for speed does not change. Multiplying the biach by the current value of the coefficient from array B (depending on the correction point) determines the magnitude of the error on the load on the 5.1 bit that would occur at the given moment with the predicted and desirable transition process. The array of coefficients B (1) is determined during preliminary simulation of the electromechanical system (the procedure for determining the coefficients is given after the operation of the device for controlling the electric drive). Next is the deviation of the real error 5 from the predicted 5ri (which takes place due to the action on the electromechanical system of the bit feed regulator - the hoist system of the drill pipe perturbations and possible inaccuracy in determining the coefficients) and using a predefined coefficient M (the algorithm for determining the coefficient see below) is calculated the value of the amplitude of the corrective control action USHM M required to compensate for disturbances in the amplitude (5 - bi). After that value

the cyclical counter I of correction points increases and is limited if a specified number of correction points N, which determine the duration of the transition process, are reached, equals 1.

But the value of the speed reference signal (until the load reference is set on the load setter 1 to the bit equal to zero), which this subroutine generates, increases by the ISM only during Tim, increasing by, „at each discrete operating time interval of the microprocessor set 4. In this case, the task for the speed u, s is limited in amplitude to the value of bmax determined by the maximum voltage of the transducer 5 and technological restrictions on the bit feed speed.

Each time after a change in the Oc, the value of the Udc counter of the discrete time intervals increases by 1. The amplitude of the control action 1 is corrected ;; w will not be performed until the Udc reaches the Tim / AT value, which means the expiration of the Tim time interval. If at the same time all correction points () are passed, then it wonders whether the error in the load on the bit has become less than permissible. If the mismatch still takes place, then this error is considered the result of a new disturbance and the regulatory process continues in this way until the condition 5 5 dop is reached. Axial load regulation is almost astatic. Acceptable error in the simulation was accepted at the level of 10E-5.

As already noted earlier, the coefficients B (1) and M used in the subroutine for controlling the axial load on the bit to calculate the control action on the load on the bit can be determined during design by preliminary modeling of the electromechanical system.

It is assumed that the bit is in contact with the rock of arbitrarily given hardness. We set a certain value of speed, which remains unchanged in the process of determining the coefficients. Choosing the appropriate weight task, artificially balance the electromechanical system.

An electromechanical system optimized with respect to speed by one of the known methods 4 is supplied with a disturbing signal of arbitrary amplitude via a load channel. The largest transient error in the load on the bit is removed. The error by which the regulation is supposed to be built is fixed in I s after the application of the impulse. The coefficient Av is calculated, which is equal to the ratio of the final mismatch to the magnitude of this error.

Similarly, the signal U is applied to the electromechanical system, from setting the speed in the form of a unit control unit linearly increasing during Tim (i.e., increasing by 1) and a mismatch is recorded at the end of the process. The coefficient Au is calculated, which is equal to the ratio of 1 to the value of the final mismatch.

If an error is detected at time k, then the control action required to compensate for the applied perturbation can be calculated from its value using the total proportionality coefficient over the discrete interval with which the device for controlling is operated. Since the rate of change of speed is out of hand for technological reasons, I control it; its effect increases linearly during the time interval T „m.

 while the transition curve for the load on the bit is smooth (there is no oscillation), the T ™ value is fixed and used in the regulation. Otherwise, we increase the rise time of the controlled action of Тнм pa 0.5 s (initially Tim is set equal to 0.5 s) and again we evaluate the resulting curve.

Thus, in response to the disturbing effect, the device for controlling the number of revolutions and the moment of the electric drive acts on the engine 6, and, therefore, ultimately on the bit calculated control action. As a result of applying to the electromechanical system the controlling and repulsive effects of the opposite direction, the electromechanical system must come to equilibrium. But due to a certain delay of the control pulse, a deviation nevertheless takes place, and the deviation at each moment of time k-i-i is proportional to the magnitude of the error at time k. The error at each time moment k-i-i (where, .., N) is compared with and the corresponding proportionality coefficient B (i) is calculated. This transient is adopted as a reference and it builds on the regulation of the load on the bit according to the algorithm shown in figure 4. Coefficients B (i). (..., N) allow us to predict the development of the transient process with arbitrary disturbance in the electromechanical system according to the initially detected mismatch (error in the load on the bit).

When modeling, the coefficients B (1) and M are determined with each increase in the length of the drill pipe, for example, by 1000 m (within the depth of the drilled well).

Simulation of transients in the bit feed regulator system - the tapsva system - drill pipe string with such a device for controlling the speed and torque of the electric drive (the P-law of speed control and the PI-law of motor current control were used) show that the control system almost completely controls the transition process in the mechanical part. Moreover, the quality of electromagnetic transients is quite acceptable, because the amplitude of the current does not exceed one third of the permissible value, and the integral current is even less than in the known device, which means that the regulation occurs at a lower current consumption. Although the engine speed in the proposed device varies at a much faster pace than in the known device, the acceleration does not exceed the technologically specified limits. At the same time, the dynamic error but the load on the bit decreases several times, and the process almost ends in 4 s instead of 130 in the original system. Moreover, the load due to changes in hardness changed from 1 to 4 ton-force. The case of a sudden change in load up to 20 tf was simulated in the same way, while the relative dynamic indicators of the two systems remain almost the same, and the current amplitude does not exceed half the allowable, although such a change in hardness both in amplitude and in rate is not typical for this system. The most severe case was simulated. With a smoother change in hardness, the effectiveness of the proposed device increases significantly.

Similarly to the dynamic load on the bit, the dynamic loads in all nodes of the drill pipe string are reduced, which increases not only the life of the bit itself, but also the drill pipe, because the load on the couplings connecting them is reduced. All of this, as noted above, increases drilling productivity.

A device for controlling the number of revolutions and the moment of electric drive of the bit feed regulator may comprise a weight sensor (not shown in FIG. 1) connected to the input of the microprocessor set 4 (see FIG. 1). However, since the weight of the column more closely matches the tension of the running branch of the hoist rope than the tension of the fixed branch where the weight sensor is installed, the latter is used for additional visual monitoring of the progress of the change in the load on the bit.

1.Motsohein B.I. Electrotechnical complexes and systems of drilling rigs, M .: Nedra, p. 166.

2. USSR Certificate of Authorship No. 1452944, BI No. 3, 1989

3.Eyuborykin A.V., Liyovetsky G.P., etc. Single-chip mncro-computers, -1994, p. 107,

4.Azarov B.Ya., Ilyashenko L.A., Ilyashenko N., L. etc. The use of microprocessors in an automated electric drive. - M .: Mosk. energ institute 1989.-94 p., P. 66.

5.Pervozvansky A.A. The course of the theory of automatic control: Textbook. benefits M .: Science. Ch. ed. physical mat, lit. 1986 - 616 p., P. 130.

6. Basharin A.V., Postnikov Yu.V. Examples of calculating an automated electric drive on a computer: Textbook. manual for universities - 3rd ed. - L .: Energoatomizdat. Leningrad, det., 1990. - 512 p., Ill., S, 250,

12 Literature:

Claims (2)

1. A device for controlling the number of revolutions and the moment of the electric drive, comprising a bit load adjuster, a current sensor and a speed sensor, characterized in that it is equipped with a microprocessor kit that performs the functions of regulating the axial load on the bit, the speed and current of the electric drive, its inputs are connected to a bit load adjuster, a current sensor and a speed sensor, and a converter supplying the bit feed regulator motor is connected to its output, and the microprocessor set is made with the possibility of the implementation of the algorithm of the program for regulating the axial load on the bit in the bit feed regulator, the algorithm for determining the static current of the engine and the algorithm for calculating the control action in the subroutine for regulating the axial load on the bit.  2. The device according to claim 1, characterized in that it is equipped with a weight sensor connected to the input of the microprocessor kit.