Method for control of a hydrocarbon production well

Abstract

It is provided a computer-implemented method for control of a hydrocarbon production well equipped with an artificial activation system, the artificial activation system comprising either a gas lift system or an electrical submersible pump (ESP). The method comprises providing one or more target values each of a respective production parameter and each corresponding to a respective setpoint parameter, and for each set point parameter, providing a respective regulator module and repeatedly applying a real-time variation to the real-time value of the respective setpoint parameter. The method forms an improved solution for control of a hydrocarbon production well equipped with an activation system.

Description

[0001] METHOD FOR CONTROL OF A HYDROCARBON PRODUCTION

[0002] WELL

[0003] Technical field

[0004] The present disclosure relates to the field of control of hydrocarbon production wells equipped with artificial activation systems, and more specifically to a computer-implemented method for control of a hydrocarbon production well equipped with an artificial activation system, the artificial activation system comprising either a gas lift system or an electrical submersible pump (ESP). It is also provided a computer program, a data storage medium, a system, and equipment, for control of such hydrocarbon production wells according to the method.

[0005] Technical background

[0006] Hydrocarbons are often found in underground reservoirs, their production being made possible by the drilling of wells to the reservoirs. Production systems are often equipped with activation systems in order to increase the flow of fluids within a production well. The artificial activation system may comprise an ESP to boost production, or a gas lift system to improve production by injecting gas into the bottom of the well. There is an interest in monitoring parameters of such a system so as to detect damage to the activation system or the well itself. These parameters may be treated by an algorithm that aims to respect various production and security constraints and operations recommendations. If the algorithm determines that one or more parameters are not conform with a predefined production target value, the algorithm can instruct a corrective action to an operating parameter of the hydrocarbon production well and / or an operating parameter of the activation system, to allow for continued stable operation of the production well. For example, for the ESP case, a method may comprise taking values provided by sensors on the motor of the pump relating to pump frequency, and may use an algorithm to analyze the values. If the frequency of the pump is considered to be too low for say, the bottom hole pressure (BHP) of the production well to achieve its target value, a corrective action may be executed to increase the pump frequency, thereby increasing the BHP. However, such methods generally involve a lot of operator interventions and specific know-how and technical expertise. Moreover, determining parameter values themselves is a complicated task for the operator, comprising for example the proportional- integral-derivative (PID) control approach. Within this context, there is still a need for an improved method that optimizes production regulation while at the same time simplifying the tasks of the operator.

[0007] It is therefore an object of this disclosure to provide a computer- implemented method for control of a hydrocarbon production well equipped with an artificial activation system, the artificial activation system comprising either a gas lift system or an electrical submersible pump (ESP), the method comprising: providing one or more target values each of a respective production parameter and each corresponding to a respective setpoint parameter, each setpoint parameter being an operating parameter of the hydrocarbon production well, at least one target value corresponding to a respective setpoint parameter which is an operating parameter of the artificial activation system; and for each setpoint parameter: o providing a respective regulator module, the regulator module being a monotonic function that outputs, for an input error value respective to the setpoint parameter, a variation of value for the respective setpoint parameter, the function outputting a zero variation when the input error value is zero, the function being strictly monotonic for a first range of input error values, the input error values of the first range being negative, the function further being strictly monotonic for a second range of input error values, the input error values of the second range being positive; and o repeatedly:

[0008] ■ determining a real-time target error value for the target value corresponding to the setpoint parameter;

[0009] ■ determining a real-time input error value respective to the setpoint parameter based on the real-time target error value;

[0010] ■ inputting the real-time input error value into the respective regulator module, thereby outputting a real-time variation of value for the respective setpoint parameter; and ■ applying the real-time variation to the real-time value of the respective setpoint parameter.

[0011] The method may comprise one or more of the following features:

[0012] - the function outputs a zero variation for a third range of input error values, the third range including the input error value which is zero;

[0013] - the function is constant before the first range and after the second range;

[0014] - the function includes: o a maximum ramp-down zone corresponding to the function being constant before the first range, the input error values being lower than a first negative threshold (-DZ) and the output variation being constant in said maximum ramp-down zone; o a first damping zone corresponding to the first range of input error values, the input error values being higher than the first negative threshold (-DZ) but lower than a second negative threshold (-TZ) and the output variation being strictly monotonic in said first damping zone; o a tolerance zone corresponding to the third range of input error values, the input error values being higher than the second negative threshold (-TZ) but lower than a first positive threshold (TZ) and the output variation having a zero variation; o a second damping zone corresponding to the second range of input error values, the input error values being higher than the first positive threshold (TZ) but lower than a second positive threshold (DZ) and the output variation being strictly monotonic in said second damping zone; o a maximum ramp-up speed zone corresponding to the function being constant after the second range, the input error values being higher than the second positive threshold (DZ) and the output variation being constant in said maximum ramp-up zone;

[0015] - for at least one setpoint parameter, the determining of the real-time input error value respective to the at least one setpoint parameter comprises at each repetition: o determining one or more real-time limit error values each for a respective limit value of a production or operating parameter corresponding to the at least one setpoint parameter; o selecting a lowest error value amongst the real-time target error value and the one or more real-time limit error values; o using the lowest error value as the real-time input error value; and / or o for at least one other setpoint parameter, the determining of the real-time input error value respective to the at least one other setpoint parameter comprises at each repetition: o using the real-time target error value as the real-time input error value;

[0016] - each real-time target error value is a weighted difference between the target value of the corresponding production parameter and the effective real-time value of the corresponding production parameter, and / or each real-time limit error value is a weighted difference between the respective limit value and the effective real-time value of the respective production or operating parameter;

[0017] - the respective setpoint parameter is a remote control valve (RCV) setpoint parameter;

[0018] - the method further comprises repeatedly implementing a respective increase pause function, the function being a safety measure that pauses applying the real-time variation to the real-time value when a parameter value associated with the setpoint parameter reaches a respective critical measurement variation limit;

[0019] - the respective critical measurement variation limit is a bottom hole pressure decrease rate;

[0020] - for the case of the artificial activation system comprising a gas lift system, the respective critical measurement variation limit is either a bottom hole pressure decrease rate or a wellhead pressure decrease rate;

[0021] - pausing applying the real-time variation to the real-time value comprises pausing opening the RCV;

[0022] - for the case of the artificial activation system comprising a gas lift system, the respective setpoint parameter is a injection gas rate setpoint parameter;

[0023] - pausing applying the real-time variation to the real-time value comprises pausing a gas injection; - for the case of the artificial activation system comprising an ESP, the respective setpoint parameter is a pressure control valve (PCV) setpoint parameter;

[0024] - pausing applying the real-time variation to the real-time value comprises pausing opening the PCV;

[0025] - the method further comprises, for the case of the artificial activation system comprising a gas lift system, repeatedly implementing a respective decrease pause function after the increase function, the function being a safety measure that pauses applying the real-time variation to the real-time value according to another respective critical measurement variation limit;

[0026] - pausing applying the real-time variation to the real-time value comprises pausing closing the RCV;

[0027] - for case of the artificial activation system comprising an ESP, the respective setpoint parameter is a frequency setpoint parameter of the ESP;

[0028] - for the case of the artificial activation system comprising an ESP, pausing applying the real-time variation to the real-time value comprises pausing increasing the ESP frequency;

[0029] - the method further comprises implementing a stepper module which, after the outputting of a predetermined number of real-time variations, allows the applying of the real-time variation to the realtime value;

[0030] - for the case of the artificial activation system comprising an ESP, the one or more production target values are selected from motor frequency, well head temperature (MF), bottom hole pressure (BHP), well head pressure (WHP), liquid flow rate (Qliq), and / or casing head pressure (CHP);

[0031] - for the case of the artificial activation system comprising a gas lift system, the one or more target values are selected from RCV degree of opening, RCV differential pressure (dP_RCV), liquid flow rate, well head pressure, bottom hole pressure and / or injection gas lift rate (IGR);

[0032] - for the case of the artificial activation system comprising an ESP, the one or more limit values include bottom hole pressure, well head pressure and / or motor current (MC); - for the case of the artificial activation system comprising a gas lift system, the one or more limit values include bottom hole pressure and / or well head pressure;

[0033] - at least one target value is user-selected among at least two possibilities corresponding to the same respective setpoint parameter, for example, three of the target values, or five of the target values;

[0034] - the respective regulator module comprises at least one constraint to assist in the outputting of the respective value of the respective setpoint parameter, for example a range of an output, a maximum ramp up speed of the output, and / or maximum ramp down speed of the output;

[0035] - a value of the at least one constraint is a user-adjusted value; and / or

[0036] - another value of the at least one constraint is a predetermined value. It is also provided a computer program comprising instructions which, when executed by a processor, cause the processor to perform the method.

[0037] It is also provided a data storage medium having recorded thereon the computer program.

[0038] It is also provided a system for control of a hydrocarbon production well equipped with an artificial activation system, the artificial activation system comprising either a gas lift system or an ESP, the system comprising: o a memory having recorded thereon the computer program; and o a processor for executing the program.

[0039] It is also provided equipment for a hydrocarbon production well, the equipment including an artificial activation system, the artificial activation system comprising either a gas lift system or an ESP, the equipment further including the system.

[0040] Brief description of the drawings

[0041] Non-limiting examples will now be described in reference to the accompanying drawings, where:

[0042] FIG. 1 shows an example of a hydrocarbon production well equipped with an ESP;

[0043] FIG. 2 shows an example of a hydrocarbon production well equipped with a gas lift system; FIG.’s 3-5 show an example of the method where the artificial activation system is an ESP;

[0044] FIG.’s 6-7 show an example of the method where the artificial activation system is a gas lift system;

[0045] FIG. 8 shows an example of the regulator module according to an example of the method;

[0046] FIG. 9 shows an example of implementing the stepper module according to an example of the method;

[0047] FIG. 10 shows an example of a control panel and an example of the regulator module according to an example of the method, when the activation system in an ESP activation system;

[0048] FIG. 11 shows an example of an initial production value approaching a target value according to the example of FIG. 10 (“with damping”), and an example of an initial production value approaching a target value according to the prior art (“no damping”). The examples are displayed on a graph of setpoint parameter as a function of time;

[0049] FIG. 12A and FIG. 12B show examples of application of the stepper module according to the “with damping” example of FIG. 11 ;

[0050] FIG. 13 shows an example of a user interface for applying the method.

[0051] Detailed description

[0052] It is provided a computer-implemented method for control of a hydrocarbon production well equipped with an artificial activation system, the artificial activation system comprising either a gas lift system or an electrical submersible pump (ESP). It is further provided a system for control of a hydrocarbon production well equipped with an artificial activation system, the artificial activation system comprising either a gas lift or an ESP, according to the method.

[0053] The method comprises providing one or more target values each of a respective production parameter and each corresponding to a respective setpoint parameter. Each setpoint parameter is an operating parameter of the hydrocarbon production well. At least one target value corresponds to a respective setpoint parameter which is an operating parameter of the artificial activation system.

[0054] The method also comprises performing the following steps (i.e. production regulation steps) for each setpoint parameter.

[0055] The steps comprise providing (e.g. computing or retrieving from memory) a respective regulator module. The regulator module is a monotonic function that outputs, for an input error value respective to the setpoint parameter, a variation of value for the respective setpoint parameter (i.e. a value for increasing or decreasing the value of the setpoint parameter). The function outputs a zero variation (i.e. a null variation or non-variation) when the input error value is zero. The function is strictly monotonic for a first range of input error values. The first range of input error values are negative. The function is also strictly monotonic for a second range of input error values. The second range of input error values are positive.

[0056] The steps also comprise a series of actions which are repeated (i.e. iterated over time).

[0057] The series of actions comprises determining a real-time target error value for the target value that corresponds to the setpoint parameter. The series of actions also comprises determining, based on the real-time target error value, a real-time input error value respective to the setpoint parameter. In other words, the method determines a value to be inputted to the respective regulator module so as to approach the target value, possibly while meeting some security or operating constraints (e.g. the method involving one or more limit error values to represent such constraints, in some examples discussed later).

[0058] The series of actions further comprises inputting the real-time input error value into the respective regulator module. The method thereby outputs a realtime variation of value for the respective setpoint parameter. The series of actions further comprises applying the real-time variation to the real-time value of the respective setpoint parameter. The method may thereby modify the value of the respective setpoint parameter, at repetitions / iterations when the outputted real-time variation is not a zero variation (wherein the method may comprise such repetitions / iterations).

[0059] The method may initially start with an input error value that is different to a target value, i.e. a target input error value, the target value being the value to be achieved, i.e. an end point. By target error, it is meant a value that is different to the target value and optionally to a range of values approximate to the target value. The input error value used to control the setpoint parameter may then be based on the target error value. In other words, the target error value can govern applying the variation to the setpoint parameter. The method determines a real-time target error value for the target value corresponding to the setpoint parameter, in other words an actual or current target error value. The method determines a real-time input error value respective to the setpoint parameter based on the real-time target error value. In other words, the real- time input error value may too be a real-time target error value. Alternatively, the real-time input error value may not be a real-time target input error value but another error value related to the real-time target error value. Such a realtime input error value may be a real-time limit error value for a respective limit value. The limit error value, further described later, can be a security measure, after for example a first iteration or more than one iterations or repetitions of the method. The real-time limit error value can be related to the real-time target error value in that the real-time limit error value is of a limit value designed to regulate the achieving of the target in the event of for example an overshooting of a parameter of the system (for example, the target may be a bottom hole pressure and the limit value may also be a bottom hole pressure - during the repetitions the target may be overshot and consequently the limit approached, or for another example the target may be a bottom hole pressure and the limit may be motor current - during the repetitions in approaching the target, the motor current limit may consequently be approached).

[0060] For example, the method may begin by using the real-time target error value as the real-time input error value. After a number of repetitions, a production parameter, such as an operation parameter or other production parameter, may approach a limit value. If the parameter value is close to its limit value (e.g. closer to its limit than other production parameters amongst a group of parameters are to each of their respective limits, and closer to its limit than the real-time target error is to the target), the system may regulate the value by taking the limit value as the real-time input error value and applying the outputted real-time variation to the real-time value of the respective setpoint parameter. Consequently, the setpoint parameter can arrive back to a value sufficiently below the limit. The following repetitions or iterations may then go back to using the real-time target error value as the real-time input error value so as to eventually achieve the target.

[0061] Such a method and system form an improved solution for control of a hydrocarbon production well equipped with an activation system.

[0062] By providing, for each setpoint parameter, a respective regulator module, the method enables approaching the setpoint value (and hence, the target value) at a rate that reduces potential damage that may occur to the well components, such as components of the activation system. In other words, the closer the error value gets in approaching zero, the smaller increments or reductions (i.e. the variation for the value of the respective setpoint parameter) made to approach the setpoint value become. This in turn assists in preventing an operating component of the hydrocarbon well, such as an operating component of the activation system, from too drastically adjusting a value of an operating parameter of the hydrocarbon production well (such as an operating parameter of the artificial activation system) to reach a setpoint, or from too brusquely stopping acceleration towards the setpoint once it has been reached, thus causing damage to the component and perhaps consequently, the well itself.

[0063] Moreover, providing, for each setpoint parameter, a respective regulator module allows for effectively controlling a number of setpoint parameters simultaneously and hence further improving protection of well components and the well itself. Each respective setpoint parameter may relate to a controllable parameter of the production well, such as one of the hydrocarbon production well operating components of the system. An example may include a parameter of the well itself or the activation system, such as the pump or a valve, such as the remote control valve (RCV) setpoint.

[0064] By providing the respective regulator module, it is understood that the regulator module may be configured prior to its repeated implementation, i.e. the function of the regulator module is preconfigured. Alternatively or additionally, the operator may provide values for any of the parameters of the regulator module.

[0065] The method enables ensuring production regulation. The method comprises providing one or more production target values, each of a respective production parameter. By target value, it is meant a value to be achieved or aimed towards. Providing the one or more target values facilitates work of the operator (who may select the one or more production target values from a selection of production target values), as only providing one or more target values is sufficient in allowing the method to provide a respective module and repeatedly apply the real-time variation to a real-time value of the respective setpoint parameter. In other words, the method can function with a reduced operator input. Further, the target values themselves may be simple for the operators to define and therefore also ease the work of the operator. In addition, applying a real-time value allows controlling and stabilizing the well in real-time. This enables protecting damage to any surface installations, well equipment, and to stabilize the flow of the hydrocarbons and hence a smooth ramp up of well production. This in turn allows for maximizing and maintaining the production of the target defined by the operator.

[0066] At least one (e.g. each) of the one or more production target values may be a value associated with the production of hydrocarbons from the well. The method may comprise selecting, for example, for the case of the artificial gas system comprising an ESP, at least one (e.g. each) of the one or more production target values from motor frequency (MF), well head temperature (WHT), bottom hole pressure (BHP), well head pressure (WHP), liquid flow rate (Qliq), and / or casing head pressure (CHP). Alternatively, the method may comprise selecting, for example, for the case of the artificial activation system comprising a gas lift system, at least one (e.g. each) of the one or more production target values, from RCV degree of opening, RCV differential pressure (Dp_RCV), liquid flow rate, well head pressure, bottom hole pressure and / or injection gas lift rate (IGR).

[0067] Regardless of the activation system, at least one target value may be user-selected (or operator-selected) among at least two possibilities corresponding to the same respective setpoint parameter, for example, three of the target values, or five of the target values. When the activation system comprises an ESP, at least one target value may be user-selected among at least two possibilities corresponding to the same respective setpoint parameter, for example, three of the target values. When the activation system comprises a gas lift, at least one target value may be user-selected among at least two possibilities corresponding to the same respective setpoint parameter, for example, five of the target values. The operator may select the measurement used as target and / or set the value of the target. If the selected target is, for example, WHT_Target or BHP_Target, and the associated measurement is not available (invalidity or in maintenance inhibition) the regulation may switch to the MF_Target. If WHP or CHP is not available (invalidity or in maintenance inhibition) the method may implement a deactivated sequence (O-DESACTIVATED).

[0068] Each target value corresponds to a respective setpoint parameter. Each setpoint parameter is an operating parameter of the hydrocarbon production well, i.e. a parameter of the production well directly or indirectly related to the target value whose setpoint assists in achieving the target value. A target or production parameter (i.e. the parameter to which the target value belongs, being for example a parameter associated with the production of hydrocarbons from the well) may be the same parameter as the respective setpoint parameter. Alternatively, the target parameter may be a different parameter to the respective setpoint parameter. At least one (e.g. each) setpoint parameter is an operating parameter of the artificial activation system. At least one (e.g. each) of the respective setpoint parameters, for the case of the artificial activation system comprising either an ESP or a gas lift system, may for example be a remote control valve (RCV) setpoint parameter. The RCV setpoint parameter may be a degree of opening of the valve, for example as a percentage. At least one (e.g. each) of the respective setpoint parameters may for example, for the case of the artificial gas system comprising an ESP, be selected from a pressure control valve (PCV) setpoint parameter, or a frequency setpoint parameter of the ESP. A VSD (variable speed drive) may manage the motor frequency. The frequency set point may range, for example, from 0 to 100 Hz, or for example, 0 to 80 Hz. The PCV may open or close binary according to a pressure setpoint. Alternatively, at least one (e.g. each) of the respective setpoint parameters may for example, for the case of the artificial activation system comprising a gas lift system, be selected from an injection gas rate setpoint parameter.

[0069] The method comprises providing, for each setpoint parameter, a respective regulator module. The system comprises a memory having recorded thereon a computer program according to the method. The memory may also store a database. The memory may be any hardware adapted for such storage, possibly comprising several physical distinct parts (e.g. one for the program, and possibly one for the database). The computer program may comprise instructions executable by a computer, the instructions comprising means for causing the above system to perform the method. The program may be recordable on any data storage medium, including the memory of the system. The program may for example be implemented in digital electronic circuitry, or in computer hardware, firmware, software, or in combinations of them. The program may be implemented as an apparatus, for example a product tangibly embodied in a machine-readable storage device for execution by a programmable processor. The program of the system may comprise the regulator module, and the processor may execute its functioning. The processor may be a programmable processor executing a program of instructions to perform the method steps or the functions of the method by operating on input data and generating output. The processor may thus be programmable and coupled to receive data and instructions from, and to transmit data and instructions to, a data storage system, at least one input device, and at least one output device. The regulator module outputs, for an input error value respective to the target value, a variation for the value of the respective setpoint parameter. This variation enables adjusting the value of the respective setpoint parameter. This in turn enables impacting (i.e. adjusting) the value of the target production parameter so that it can approach said target value. For example, the production parameter to which the target value belongs may be BHP (i.e. the target value is a BHP target value), and the respective setpoint parameter may be ESP motor frequency. The BHP target value may be equal to a gauge pressure of 14.5 MPa but the value of the BHP may only be equal to a gauge pressure 14.46 MPa. The method may adjust the value of the motor frequency (the respective setpoint parameter) from, for example, 47 Hz to 44 Hz according to the outputted variation of 0.5 Hz / min. Consequently, the BHP can increase to reach its target value of an gauge pressure of 14.5 MPa.

[0070] Once the variation of value results in an achieving of a target (or not exceeding a limit), for example if, over a predetermined period of time no variation is required, the method may achieve an optimized production phase and may stop applying the variation until the effective values relating to each target start to stray away from their respective target, and / or until the effective values relating to each limit start to go over their respective limit. Additionally or alternatively, the method may start to apply (or continue to apply) the method to different targets and limits of the production system. Conversely, in the event of a production fault, the method may comprise a step of executing a reduced rate that performs a corrective action when at least one of a first level of anomalies called “reduced rate faults” is detected. The faults may include low motor current (MC_L1 ), high motor current (MC_H1 ), motor current instability (XXI_H), high motor winding temperature (MWT_H), high pump discharge pressure (PDP_H1 ), high pump discharge temperature (PDT_H1 ), low choke differential pressure (dP_RCV_L1 ), high choke differential pressure (dP_RCV_H1 ), high motor vibration (VTX_H1 or VTY_Y_H1 or VTZ_H1 ), high motor leakage current (MCLk_H1 ), high cable fault resistance (CFR_H1 ), and / or high pump differential pressure (dP_ESP_H1 ).

[0071] Applying the real-time variation to the real-time value of the respective setpoint parameter may comprise the processor executing program instructions to the various components of the well. For example, the program may instruct an adjustment (being an increase or a decrease) of the motor frequency, or of the opening of the RCV or PCV, or of the injection gas lift rate (IGR) setpoint parameter for the pressure control system (PCS) pressure valve control (FCV) regulation. The instructing may comprise communicating the instructions to the each respective component, or to a device controlling the operating of a respective component, for example an actuator. The executing of the instructions may comprise wirelessly communicating the instructions. Alternatively executing of the instructions may comprise communicating the instructions via a wired network. It is also provided equipment for a hydrocarbon production well, the equipment including an artificial activation system, the artificial activation system comprising either a gas lift system or an ESP, the equipment further including the system for implementing the method. The equipment may also comprise any actuators and / or valves of the hydrocarbon production well (e.g. RCV, PCV), production liquid or production gas flow lines, sensors to provide measurement information and / or any data acquisition material to facilitate the providing of measurement information.

[0072] The regulator module is a monotonic function. The function may be symmetrical on either side of the y-axis in that the function on one side of the y-axis may be an inverted glide reflection of the function on the other side of the y-axis. Alternatively, the function may be asymmetrical on either side of the y-axis in that the function on one side of the y-axis may not be an inverted glide reflection of the function on the other side of the y-axis. The function may be a linear function. The function may be an entirely non-decreasing function. The function may be an increasing function. For example, if the input error value is a negative value corresponding to a target or limit value (i.e. effective value) which is too high, the function can output a negative variation value (ramp down). If the input error value is a positive error value corresponding to a target or limit value which is too low, the function can output a positive variation value (ramp up). Alternatively, the function may be an entirely non-increasing function. The function may be a decreasing function. For example, if the input error value is a negative value corresponding to a target or limit value which is too low, the function can output a positive variation value (ramp up). If the input error value is a positive error value corresponding to a target or limit value which is too high, the function can output a negative variation value (ramp down). The negative input error value corresponding to an effective value which is too high may be considered as a positive input error value corresponding to an effective value which is too high. For example, if the effective value is a limit value, which is over the limit, may be considered to have a negative error value (limit minus effective value), or a positive error value (effective value minus limit). For another example, if the effective value is a target value, which is over the target, may be considered to have a negative error value (target minus effective value), or a positive error value (effective value minus target). Likewise, the positive input error value corresponding to an effective value which is too low can be considered as a negative input error value corresponding to an effective value which is too low. In other words, whether the function is increasing or decreasing may depend on the definition of the input error value. The function outputs a zero variation when the input error value is zero. In other words, if the input error value is zero, the target value is already achieved. The function is strictly monotonic for a first range of input error values (i.e. continuous set of input values of non-zero length).

[0073] The function may be strictly increasing for the first range of input error values. The input error values are negative for the first range. The function may be a linear strictly increasing monotonic function for the first range of input error values. The function further is strictly monotonic for a second range of input error values. The function may be strictly increasing for the second range of input error values. The function may be a linear strictly increasing monotonic function for the second range of input error values. The input error values are positive for the second range.

[0074] Alternatively, the function may be strictly decreasing for the first range of input error values. The function may be a linear strictly decreasing monotonic function for the first range of input error values. The function may be strictly decreasing for the second range of input error values. The function may be a linear strictly decreasing monotonic function for the second range of input error values.

[0075] The input error value is respective to the target value and based on the target error value. The input error value may be the difference between the target value and an effective or measurement value, the effective / measurement value and the target value being of the same production parameter. Sensors may provide measurement information for implementing the method, for example, in the case of ESP, pump motor frequency, pump motor current, pump motor voltage. Sensors may be one or more of the system operating components.

[0076] The method comprises repeatedly determining a real-time target error value for the target value corresponding to the setpoint parameter. The realtime target error value may be a discrepancy from the target value. The realtime target error value may be based off a real-time measurement of the target value.

[0077] The method comprises repeatedly determining a real-time input error value respective to the to the setpoint parameter based on the real-time target error value. In other words, upon providing the respective regulator module, the method can then implement the regulator module so as to, with each repetition, adjust the setpoint parameter value so as to approach a target value (or reduce back to a limit value). Upon determining the variation for the value of the respective setpoint parameter, the method may then determine the difference between the target / limit value and a real-time measurement value, or a value related to a real-time measurement value. The real-time input error value corresponds to the input error value. That is to say, the real-time error value corresponds to the same target or limit value as the input error value. The real-time measurement value may be of the same production parameter as the target or limit value.

[0078] The method comprises repeatedly inputting the error value into the respective regulator module, thereby outputting a real-time variation of value for the respective setpoint parameter. The method comprises repeatedly applying the real-time variation to a real-time value of the respective setpoint parameter. This in turn enables the value of the setpoint parameter to approach a value that consequently influences the value of the target production parameter to approach its target value or the value of the limit production parameter to move back within its limit value. In other words, for each repetition of determining the real-time error value, inputting the respective error value into the regulator module, and applying the outputted real-time variation to the real-time value of the setpoint parameter, the value of the production parameter can get closer to the target value. When the value of the production value is equal to the target value, i.e. when the real-time error value is equal to zero, the method may stop applying the real-time variation to the real-time value of the setpoint parameter. In this case, the method may continue to monitor the target production parameter, i.e. the method may repeatedly determine the real-time error value and repeatedly input the respective error value into the regulator module for outputting the real-time variation. Additional aspects of the method and system are now briefly discussed.

[0079] The function may output a zero variation for a third range of input error values, the third range including the input error value which is zero, i.e. a range for which the input error values can be considered sufficiently close to zero for the corresponding outputted variation to also be equal to zero. The third range may have a negative lower boundary and a positive upper boundary. Alternatively, the absolute value of the lower boundary may be different to the absolute value of the upper boundary. The third range may include the value equal to the negative lower boundary and the value equal to the positive upper boundary, in other words, the third range negative lower boundary may be greater than or equal to zero and the positive upper boundary may be less than or equal to zero. Alternatively, third range may not include the value equal to the negative lower boundary and may not include the value equal to the positive upper boundary, in other words, the third range negative lower boundary may be greater than zero and the positive upper boundary may be less zero. The absolute value of the lower boundary may be equal to the absolute value of the upper boundary. This range enables avoiding implementation of additional repetitions of repeatedly determining a real-time error value, inputting the respective error value, and applying the outputted real-time variation to the real-time value of the setpoint parameter.

[0080] The function may be constant before the first range (defining for example a fourth range) and after the second range (defining for example a fifth range). This may facilitate efficiently outputting a variation for larger input error values, for example, error values considered large enough to output a maximum variation. The outputted variation may however be small enough so that, when applied to the real-time value of the respective setpoint parameter, the subsequent real-time input error value will not be equal to zero. This can in turn reduce risk of an abrupt deceleration or abrupt stopping change in the real-time value of the respective setpoint parameter. Before the first range, the input error values may be lower than a first threshold value. Before the second range, the input error values may be greater than a second threshold value. A maximum ramp-down zone may correspond to the function being constant before the first range. In other words, “zone” can be considered to be equal to a “range” or “series” of values having a particular characteristic, the characteristic in this case being that the zone comprises certain input error values for which the regulator module applies a maximum ramp-down output variation. The same understanding can be applied to further described use of “zone”. That the zone may “correspond to” the function being constant before the first range, it can be understood that the input error values of the zone are the same as those of the first range, and that the output variation values of the zone are the same as those of the first range. The same understanding can be applied to further described use of “correspond to”. The input error values may be lower than a first negative threshold (-DZ) and the output variation may be constant in said maximum ramp-down zone.

[0081] A first damping zone may correspond to the first range of input error values. The input error values of the first damping zone may be higher than the first negative threshold (-DZ) but lower than a second negative threshold (-TZ) and the output variation may be strictly monotonic in said first damping zone. The output variations of the damping zone enable a deceleration towards the target zone, and in turn protect well equipment and the well. A tolerance zone may correspond to the third range of input error values. The input error values of the tolerance zone may be higher than the second negative threshold (-TZ) but lower than a first positive threshold (TZ) and the output variation may have a zero variation. The input error values of the tolerance zone (i.e. the third range) may be evenly distributed on either side of a zero input error value. Alternatively, the total number of positive input error values of the tolerance zone may be greater than the total number of negative input error values.

[0082] A second damping zone may correspond to the second range of input error values. The input error values may be higher than the first positive threshold (TZ) but lower than a second positive threshold (DZ) and the output variation may be strictly monotonic in said second damping zone.

[0083] In other words, each of the first and second damping zones may lie on either side of the tolerance zone. The first range of input error values may be equal to the second range of input error values. The damping may within either of the first or second damping zones reduce the acceleration towards the target value by a predetermined period of time, for example, every two seconds instead of every second. The regulator module may output a variation for the input error value equal to the second negative threshold (-TZ) that is of a greater absolute value than the variation for the input error value equal to the first positive threshold (TZ). Alternatively, the module may output a variation for the input error value equal to the second negative threshold (-TZ) that is of a smaller absolute value than the variation for the input error value equal to the first positive threshold (TZ). The regulator module may output (provide a response of the method) a variation range that is different for the ramp up than it is for the ramp down. The regulator module may output a larger range of variation values for the first range than for the second range. Alternatively, the regulator module may output a larger range of variation values for the second range than for the first range.

[0084] A maximum ramp-up speed zone may correspond to the function being constant after the second range. The input error values may be higher than the second positive threshold (DZ) and the output variation may be constant in said maximum ramp-up zone.

[0085] The respective regulator module may comprise at least one constraint to assist in the outputting of the respective value of the respective setpoint parameter, for example a range of an output, a maximum ramp up speed of the output, and / or maximum ramp down speed of the output. A value of the at least one constraint may be a user-adjusted value. In this way, the user can adapt the module as per the desired function. Another value of the at least one constraint may be a predetermined value. The constraint may depend on or relate to, for example, known or predetermined tolerances of the production system.

[0086] The method may comprise providing one or more limit values. The limit value may be a maximum or minimum value or threshold value relating to the setpoint parameter which is to be avoided. The operator may provide the limit value, or the limit value may already be known to the system.

[0087] For at least one setpoint parameter (i.e. each setpoint parameter being an operating parameter being an operating parameter of the hydrocarbon production well, for example an operating parameter of the artificial activation system), the determining of the real-time input error value respective to the at least one setpoint parameter may comprise determining a real-time target error value for the target value corresponding to the at least one setpoint parameter. The operator may select the target value corresponding to the at least one setpoint parameter, and by that also a target parameter of the target value (i.e. the variable of which the target value belongs to, for example, the target parameter is motor frequency and the target value is 60 Hz) amongst a group of target values corresponding to the at least one setpoint parameter. Alternatively, there may be only one target value (and thereby a target parameter) corresponding to the at least one setpoint parameter, in which case the operator need not make a selection. The operator may provide the target value. Alternatively, the value may be a predetermined value of the system.

[0088] For at least one setpoint parameter, the determining of the real-time input error value respective to the at least one setpoint parameter may comprise a number of steps at each repetition. The method may comprise a step of determining one or more real-time limit error values each for a respective limit value of a production or operating parameter corresponding to the at least one setpoint parameter. In other words, like for each respective target value, each respective limit value (and the hence limit parameter of the limit value, i.e. the variable of which the target value belongs to, for example, the limit parameter is motor current and the limit value is a threshold value for the rated current), may be of a respective production parameter (for example, bottom hole pressure, wellhead temperature), each corresponding to a respective setpoint parameter, each setpoint parameter being an operating parameter (for example, a parameter relating to an equipment of the well, for example motor current) of the hydrocarbon production well. At least one limit value may correspond to a respective setpoint parameter which is an operating parameter of the artificial activation system.

[0089] For the case of the artificial activation system comprising an ESP, the one or more limit values may include bottom hole pressure, well head pressure and / or motor current (MC). For the case of the artificial activation system comprising a gas lift system, the one or more limit values may include bottom hole pressure and / or well head pressure. The method may comprise considering multiple limit values, i.e. determining multiple real-time limit error values each for a respective limit value. The operator may provide at least one of the at least one limit values. Alternatively, at least one of the at least one limit values may be a predetermined value of the system. The limit parameter (i.e. the parameter to which the limit value belongs) may be the same parameter as the respective setpoint parameter. Alternatively, the limit parameter may be a different parameter to the respective setpoint parameter.

[0090] The target value and a limit value of the at least one limit values may be values of the same parameter, for example bottom hole pressure, the target value being that of a bottom hole pressure target and the limit value being of a bottom hole pressure limit. Alternatively, target value and a limit value of the at least one limit values may be values of different parameters.

[0091] The number of steps for the determining of the real-time input error value respective to the at least one setpoint parameter, for the at least one setpoint parameter may comprise a step of selecting a lowest error value amongst the real-time target error value and the one or more real-time limit error values. The practice may be referred to as applying a pass low filter. A lowest error value being the real-time target error value would mean that the real-time target error value is closer to the target value than the one or more real-time limit error values are to their respective limit value. Conversely, a lowest error value being a real-time limit error value would mean that the realtime limit error value is closer to its respective limit value than the real-time target error value is to the target value, and closer to its respective limit value than any of the other real-time limit error values are to their respective limit value (if there are any other limit values).

[0092] The number of steps for the determining of the real-time input error value respective to the at least one setpoint parameter, for the at least one setpoint parameter may comprise a step of using the lowest error value as the real-time input error value. Selecting the lowest error value can facilitate the work of the regulator module as it enables focusing on the error value which should result in the minimal number of outputted variations, thus allowing for a more efficient approaching of the target value. Additionally or alternatively, the method may comprise for at least one other setpoint parameter, the determining of the real-time input error value respective to the at least one setpoint parameter. In other words, the method may determine in parallel the real-time input error value respective to at least one other setpoint parameter, and also the real-time input error value respective to at least one other setpoint parameter. The setpoint parameters may therefore be different setpoint parameters. This facilitates managing multiple parameters of the hydrocarbon production well simultaneously. This may comprise determining a real-time target error value for the target value corresponding to the at least one other setpoint parameter. The target parameter of the target value being the only parameter, the operator need not make a selection. The operator may provide the target value. Alternatively, the value may be a predetermined value of the system. The number of steps for the determining of the real-time input error value respective to the at least one setpoint parameter, for the at least one setpoint parameter may then comprise a step of using the real-time target error value as the real-time input error value.

[0093] According to an example, for the case of the ESP, the operator may make a selection of a target value (i.e. the operator may select the target parameter and may input a value, or the value may be predetermined by the system) amongst a group of target values corresponding to the at least one setpoint parameter. The setpoint parameter may be a frequency setpoint parameter. The selection may be amongst three target options, for example motor frequency target (MF_Target), wellhead temperature target (WHT_Target) and bottom hole pressure target (BHP_Target). The system may determine a real-time target error value for the selected target value. The method may also comprise determining a real-time limit error value for each respective limit value of a group of limit values, for example of three limit values (each limit value corresponding to being of a production or operating parameter corresponding to the at least one setpoint parameter). The limit parameters of the limit values may be bottom hole pressure, motor current, and wellhead pressure. The operator may select the limit values, or the values may be predetermined, the values being BHP_Limit, MC_Limit, and WHP_Limit. The system may determine a real-time limit error value for each limit value. The method may then select the lowest error values amongst each of the four error values. The method may then use the lowest error value as the real-time input error value. Additionally or alternatively, for at least one other setpoint parameter, the method may simultaneously determine the real-time input error value respective to the at least one other setpoint parameter. The other setpoint parameter may be an RCV setpoint parameter. The method may determine a real-time target error value for the target value corresponding to the at least one other setpoint parameter, the target value in this case being a wellhead pressure target (WHP_Target). The operator may select the target value, or the value may be predetermined. The method may then use the real-time target error value as the real-time input error value.

[0094] Additionally or alternatively, for at least one yet another setpoint parameter, the method may simultaneously determine the real-time input error value respective to the at least one other setpoint parameter. The other setpoint parameter may be an PCV setpoint parameter. The method may determine a real-time target error value for the target value corresponding to the at least one other setpoint parameter, the target value in this case being a casing head pressure target (CHP_Target). The operator may select the target value, or the value may be predetermined. The method may then use the realtime target error value as the real-time input error value. Consequently, the method may control either the motor frequency or RCV or PCV, or optionally multiple (e.g. all) parameters simultaneously, comprehensive control of the well and also a method that can adapt to specific requirements of the well.

[0095] If, for example the operator selects BHP as the target value for the frequency setpoint parameter, and the method is applied to each of the frequency setpoint parameter, RCV setpoint parameter and PCV setpoint parameter, if each respective parameter reaches its target (or tolerance zone) so that no variation is required, the method may implement an optimized production step. The optimized production may be ongoing when no action (i.e. applying the real-time variation to the real-time value of the respective setpoint parameter) has been implemented for a predetermined duration (Opti_D delay). During the optimized production, the production may continue without varying the setpoint parameter. If the operator selects a new production target, the regulation may start again (i.e. the method may start again with the newly provided target value of the at least one provided target values). Additionally or alternatively, the regulation may start again if there are any changes to the already achieved target value.

[0096] If the system detects one fault, the method may implement a reduced rate step. The method may comprise reducing the production rate, and may therefore pause adjusting the setpoint to reach a target value until the fault has been overcome. In addition to the pausing, for example, the corrective action may comprise, decreasing the pump frequency to a minimum frequency (MF_Mini) with a motor frequency ramp down (MF_RD). Additionally or alternatively, the corrective action may comprise maintaining WHP regulation (in other words, the method may not pause applying the variation of value to the RCV setpoint parameter for achieving the WHP target). Additionally or alternatively, the corrective action may comprise maintaining CHP regulation (in other words, the method may not pause applying the variation of value to the PCV setpoint parameter for achieving the CHP target).

[0097] According to another example, for the case of the gas lift, the operator may make a selection of a target value (i.e. the operator may select the target parameter and may input a value, or the value may be predetermined by the system) amongst a group of target values corresponding to the at least one setpoint parameter. The setpoint parameter may be an RCV setpoint parameter. The selection may be amongst four target options, for example RCV target (RCV_Target), differential-pressure-on-the-RCV (dP_RCV_target), wellhead temperature target (WHT_Target), bottom hole pressure target (BHP_Target) and liquid flow rate (Qliq). The system may determine a real-time target error value for the selected target value.

[0098] The method may also comprise determining a real-time limit error value for each respective limit value of a group of limit values, for example of two limit values (each limit value corresponding to being of a production or operating parameter corresponding to the at least one setpoint parameter). The limit parameters of the limit values may be wellhead temperature and bottom hole pressure. The operator may select the limit values, or the values may be predetermined, the values being BHP_Limit and WHT_Limit. The system may determine a real-time limit error value for each limit value. The method may then select the lowest error values amongst each of the three error values. The method may then use the lowest error value as the real-time input error value. Additionally or alternatively, for at least one other setpoint parameter, the method may simultaneously determine the real-time input error value respective to the at least one other setpoint parameter. The other setpoint parameter may be an injection gas lift rate (IGR) setpoint parameter for the pressure control system (PCS) pressure valve control (FCV) regulation.

[0099] The method may determine a real-time target error value for the target value corresponding to the at least one other setpoint parameter, the target value in this case being a injection gas lift rate target (IGR_Target). The operator may select the target value, or the value may be predetermined. The method may then use the real-time target error value as the real-time input error value. If the method is applied to each of the frequency setpoint parameter, RCV setpoint parameter and IGR setpoint parameter so that if each respective parameter reaches its target (or tolerance zone) no variation is required, the method may implement an optimized production step. The optimized production may be ongoing when no action (i.e. applying the realtime variation to the real-time value of the respective setpoint parameter) has been implemented for a predetermined duration (Opti_D delay). During the optimized production, the production may continue without varying the setpoint parameter. The regulation may start again if there are any changes to the already achieved target value. Like for the case of the ESP, if the system detects one fault, the method may implement a reduced rate step. The method may comprise reducing the production rate, and may therefore pause adjusting the RCV setpoint and / or IGR setpoint to reach a target value until the fault has been overcome. Additionally or alternatively, the corrective action may comprise maintaining adjusting the RCV setpoint and / or IGR setpoint.

[0100] An error block function may determine the real-time error value or other real-time error value. The control program of the system may comprise the functioning, and the processor may execute it. The function may take the difference between the target value and a real-time measurement value of a corresponding operating parameter of the hydrocarbon production well and / or corresponding operating parameter of the artificial activation system. The function may weight the difference by taking into account the effective range extension of the measurement during regulation (i.e. the repeated determining, inputting and applying of the regulator module). This range may be by a maximum value that can be approximate with the target (or limit) value, and by a minimum value that may be a memorized measurement taken before the start of the regulation logic (i.e. before the repeated determining, inputting and applying of the regulator module) when, for example, when the activation system comprises an ESP, the well is decompressed and a relative actuator is shut off. The function may weight the difference to express a percentage. In other words, each real-time target error value may be a weighted difference between the target value of the corresponding production parameter and the effective real-time value of the corresponding production parameter (i.e. the actual or current real-time value of the corresponding production parameter). Additionally or alternatively, each real-time limit error value may be a weighted difference between the respective limit value and the effective real-time value of the respective production or operating parameter. According an example for the case where the activation system comprises an ESP, the error may be calculated according to the following equation where the setpoint parameter is a frequency setpoint parameter (or “frequency regulator”):

[0101] Error in percent = 100 * (Target-Measure) / (Target-Static) for the frequency regulator, wherein “target” or “input 1” is a target value, “measure” or “input 2” is a measure value, and “static” or “setting” is a measure value memorized when the pump is off (after, for example tubing casing decompression).

[0102] According to another example for the ESP, the error may be calculated according to the following equation where the setpoint parameter is an RCV or PCV setpoint parameter (or “RCV regulator / PCV regulator”):

[0103] Error in percent = 100 * (Target-Measure) / (Target) for the RCV and PCV regulators.

[0104] According to an example for the case where the activation system comprises a gas lift:

[0105] Error in percent = 100 * (Target-Measure) / (Target-Static), wherein “target” or “input 1” is a target value, “measure” or “input 2” is a measure value, and “static” or “setting” is a measure value memorized after stabilization or associated parameter.

[0106] The method may comprise repeatedly implementing a respective increase pause function. The control program of the system may comprise the function, and the processor may execute its functioning. The method may apply the pause function during the applying of the real-time variation to the real-time value of the setpoint by the regulator module. The regulator output may go through the pause function, the function blocking the increase of the actuator setpoint according to a measurement variation, the measurement variation being the variation of a measurement of a parameter the same as the setpoint parameter or relating to the setpoint parameter. The function may be a safety measure that pauses applying the real-time variation to the real-time value when a parameter value associated with the setpoint parameter reaches a respective critical measurement variation limit. This function may prevent a set point increase according to a critical measurement variation limit. The critical measurement variation limit may be a parameter value or rate of change of a parameter value that can cause damage to a well component or to the well itself. For example, the respective critical measurement variation limit may be a bottom hole pressure decrease rate (draw down). In other words, achieving such a decrease rate may risk damaging the reservoir / well borehole interface that is a strategic zone for well productivity. The function may therefore pause bringing, for example the motor frequency closer to the corresponding to the target value (being of BHP in this case) so as to give the bottom hole pressure decrease rate the time to slow. Notably, when the activation system comprises a gas lift, the respective critical measurement variation limit may be either a bottom hole pressure decrease rate or a wellhead pressure decrease rate. Notably, when the activation system comprises an ESP, the respective critical measurement variation limit may be either a bottom hole pressure decrease rate or a casing head pressure decrease rate.

[0107] The respective (i.e. one of) setpoint parameter(s) may be a remote control valve (RCV) setpoint parameter. Pausing applying the real-time variation to the real-time value may comprise pausing opening the RCV. The regulator module may therefore, for an input value respective to the target value (the target value being, for example, BHP, or WHT), output a variation of the degree of opening of the valve for a provided target value. The method may then repeatedly determine a real-time error value respective to the target value, input the respective error value into the respective regulator module, and out-put a real-time variation of the degree of opening for the value (i.e. current value) of the degree of opening. The respective (i.e. one of) setpoint parameter(s) may be a pressure control valve (PCV) setpoint parameter. Like for the RCV, pausing applying the real-time variation to the real-time value may comprise pausing opening the PCV. In the event that the respective setpoint parameter is a valve parameter (e.g. RCV, PCV), the method may comprise implementing a stepper module which, after the outputting of a predetermined number of real-time variations, may allow the applying of the real-time variation to the real-time value. In other words, the method may implement the stepper module after the providing and inputting of the regulator module and before the applying. This may act as a measure to cater to well component limitations such as, those for example of a valve actuator. For example, for actuators that cannot be continuously operated, like for example an electrically actuated choke valve, the stepper function may be added in order to reduce the number of setpoint changes send to the actuator. The predetermined number of realtime variations may be a maximum number of variations per unit of time (e.g. per minute). The control program of the system may comprise the module, and the processor may execute its functioning.

[0108] For the case of the artificial activation system comprising a gas lift system, the respective (i.e. one of) setpoint parameter(s) may be an injection gas rate setpoint parameter. Pausing applying the real-time variation to the real-time value may comprise pausing applying a gas injection rate variation. This can allow for a bottom hole pressure increase rate to slow until it falls below its critical limit.

[0109] The method may comprise, for the case of the artificial activation system comprising a gas lift system, repeatedly implementing a respective decrease pause function during a start-up and / or production stage, in parallel with applying the regulator module. The control program of the system may comprise the function, and the processor may execute its functioning. This function may prevent a set point decrease according to a critical measurement variation limit. The function may be a safety measure that pauses applying the real-time variation to the real-time value according to another respective critical measurement variation limit. Pausing applying the real-time variation to the real-time value may comprise pausing closing the RCV. This may allow a wellhead pressure increase rate to slow until it falls below its critical limit.

[0110] For the case of the artificial activation system comprising gas lift, the respective setpoint (i.e. one of) parameter(s) may be an RCV setpoint parameter. Pausing applying the real-time variation to the real-time value comprises pausing opening the RCV. Pausing applying the real-time variation to the real-time value may comprise pausing opening the RCV. This may be due to an overly fast BHP or WHP decrease rate.

[0111] FIG. 1 and FIG. 2 provide examples of a hydrocarbon well equipped with an activation system. Specifically, FIG. 1 provides an example of a hydrocarbon well equipped with an activation system comprising an ESP, and FIG. 2 provides an example of a hydrocarbon well equipped with an activation system comprising a gas lift. FIG.’s 3-5 provide an example of an implementation to the method when the activation system comprises an ESP. In this example, the method comprises providing three target values, each corresponding to a respective setpoint parameter. Meanwhile, FIG. 6 and FIG. 7 provide an example of an implementation to the method when the activation system comprises a gas lift system. In this example, the method comprises providing two target values, each corresponding to a respective setpoint parameter.

[0112] FIG. 1 displays a well 150a and wellhead 150b equipped with an activation system 144 comprising ESP pump 100 connected above a separator 104, a protector 111 , a transfer hydraulic line 117, and pump motor 108 placed above a downhole gauge 110. These components of the activation system 144 are placed beneath a production packer 142. Downhole gauge measurements include ESP intake pressure (i.e. bottom hole pressure), ESP discharge pressure, ESP intake temperature (i.e. bottom hole temperature), motor winding temperature, vibration (X and Y axis), and / or tool head voltage. The pump motor 108 is connected to a variable speed drive (VSD) 118. The VSD 118 manages the motor frequency and motor current (back spin signal). The downhole gauge is connected to an acquisition module 116. The acquisition module 116 acquires data for calculation at the surface of gauge measurements including current leakage, voltage and imbalance, cable fault resistance, cable fault severity, and / or cable fault depth. Various valves are located along a liquid production line 146 for oil and water, the line 146 being connected to the pump 100 and including a downhole safety valve (DHSV) 114, an annulus safety valve (ASV) 112, a production master valve (PMV) 120, a production wing valve (PWV) 122, and an RCV valve 128. Sensors such as wellhead temperature sensor 124, wellhead pressure sensor 126, flow line temperature sensor 130b and flow line pressure sensor 130a are also located along the line 146 above the surface of the wellhead. A production gas line 148 is also connected to the wellhead 150b, along which various valves including an annulus master valve (AMV) valve 152, a PCV valve 138 and an annulus wing valve (AWV) valve 140, along with sensors 132 and 134. The sensors of FIG. 1 may provide measurement information to the system for implementing the method. FIG. 1 may be used to assist visualizing the implementation of the method as displayed in the example of FIG. 3. Cases 330a, 330b, 330c of FIG. 3 display implementation of the method for three production target values 300a, 300b, 300c. In this example, the method implements each case 330a, 330b, 330c simultaneously.

[0113] Considering case 330a, the method determines at function 302a an input error value for each of the three production target values and for each of the three production limit values 340. The error is weighted as a percentage. The operator then selects a user selects production target value 300a from the group of three target production values 300.

[0114] Upon selecting a desired target production value by the operator at selection step 304, the method determines the lowest input error value at the low pass filter 306. At the low pass filter 306, the method compares the input errors for limits values 340 to the operator-selected production target value 300a. The method then provides a respective regulator module 314a for the provided production target value 302a. The determining of the regulator module comprises implementing the production target value 302a, in this case a motor frequency target value (Max = MF_Target) along with other user- adjustable parameters 310a including the range of the output (i.e. the outputted variation), the minimum motor frequency (Min = MF_Min) the maximum ramp up (RU = MF_RU) and ramp down speed (RD = MF_RD) of the output (i.e. the outputted variation), the tolerance and damping zones (ESP_Reg_TZ, ESP_Reg_DZ) 322a. The regulator module then outputs a variation value for the value of the respective setpoint parameter, frequency setpoint 318a.

[0115] The method also comprises determining an increase pause function based on condition 320a of the bottom hole pressure decrease rate being greater than the bottom hole ramp down limit (BHP Dec. Rate > BHP_RD_limit). Upon determining the regulator module 314a and increase pause function 316a, the method once again determines a real-time error value corresponding to the input error value, i.e. corresponding to the lowest determined error value by the pass low filter 306. The increase pause function pauses applying the real-time variation parameter to the real-time (i.e. actual) frequency value of the motor 108 if the condition of the bottom hole pressure decrease rate being greater than the bottom hole ramp down limit is met. The pause may have a duration of reliant upon a measurement indicating that the bottom hole pressure decrease rate has reduced. This may, for example be by sensor 136a or sensor 128. The regulator module may then apply the real-time variation parameter to the real-time (i.e. actual) frequency value of the motor 108. In other words, the method inputs the real-time error value into the regulator module 314a, applies an increase pause function 316a, and outputs a real-time variation for the frequency setpoint 318a. The method may continue this cycle until the regulator module outputs a zero variation for the inputted real-time input error value.

[0116] Legend 312 represents the different levels used for each parameter. Level 1 is for Operator (high frequency of change, parameter daily or weekly updated). Level 1 parameters include MF_Target, WHT_Target, BHP_Target, production target selection, MF_Min, MF_RU, and MF_RD. Level 2 is for Engineer. The parameter may be updated a few times per year. Level 2 parameters include BHP_Limit, MC_Limit, WHP_Limit, and BHP_RD_Limit. Level 3 is for parameter set for the implementation. The parameter may (e.g. only) be updated if some equipment change during the life of the well. Level 3 parameters include ESP_RegTZ and ESP_RegDZ.

[0117] Considering the case 330b of FIG. 4, the operator only has one choice of production target value; wellhead pressure target value (WHP_Target) 300b. The method determines a weighted error value for the target value, and, like in case 330a, provides a regulator module 314b. The determining of regulator module 314b, comprises implementing the production target value 302b, in this case a wellhead pressure target value (WHP_Target) along with other user adjustable parameters 310b, including maximum and minimum RCV values (relating to the degree of opening of the valve) of 100% and RCV_Heel (meaning the valve is closed) respectively. The parameters 310b also include a ramp up value (RU=RCV_Reg_Ramp*RCV_RU) and a ramp down value (RD=RCV_Reg_Ramp*RCV_RD), and tolerance and damping zones (TZ=RCV_Reg_TZ, DZ=RCV_Reg_DZ) 322b. Like for case 330a, the method for case 330b also comprises determining an increase pause function based on the condition 320b of a bottom hole pressure decrease rate being greater than the bottom hole ramp down limit (BHP Dec. Rate > BHP_RD_limit). However, following the pause function, the method of the example also determines a stepper module 324b to ensure protection of the actuator when applying the setpoint. In other words, the method inputs the real-time error value into the regulator module 314b, applies an increase pause function 316b and a stepper module 324b, and outputs a real-time variation for the frequency setpoint 318b. The stepper module 324b, for an outputted realtime RCV setpoint variation from the regulator module 314b either increasing the RCV degree of opening (RCV_Reg_lnc) or decreasing the RCV degree of opening (RCV_Reg_Dec), allows the applying of the real-time RCV variation to the real-time RCV value after the outputting of a predetermined number of real-time RCV variations. The method may continue this cycle until the regulator module outputs a zero variation for the inputted real-time input error value.

[0118] Level 1 parameters in this case include WHP_Target, RCV_Reg_Ramp. Level 2 parameters in this case include RCV_Heel and BHP_RD_limit. Level 3 parameters in this case include RCV_Reg_TZ, RCV Reg DZ, RCV_RU, RCV_RD, RCV_Reg_lnc, RCV_Reg_Dec.

[0119] Considering the case 330c of FIG. 5, the operator only has one choice of production target value; casing head pressure target value (CHP_Target) 300c. Sensor 230 may monitor this value along line 248. The method determines a weighted error value for the target value, and, like in cases 330a 300b, provides a regulator module 314c. The providing of regulator module 314c, comprises implementing the production target value 302c, in this case a casing head pressure target value (CHP_Target) along with other user adjustable parameters 310c, including maximum and minimum PCV values (relating to the degree of opening of the valve) of 100% and PCV_Heel (meaning the valve is closed) respectively. The parameters 310b also include a ramp up value (RU=PCV_Reg_Ramp*PCV_RU) and a ramp down value (RD=PCV_Reg_Ramp*PCV_RD), and tolerance and damping zones (TZ=PCV_Reg_TZ, DZ=PCV_Reg_DZ) 322b. The method for case 330c comprises determining an increase pause function based on condition 320c of the casing head pressure decrease rate being greater than a casing head decrease rate (CHP Dec. Rate > CHP_RD_limit). Following the increase pause function 316c, the method of the example also determines a stepper module 324c to ensure protection of the actuator when applying the setpoint. The stepper module 324c, for an outputted real-time PCV setpoint variation from the regulator module 316c either increasing the PCV degree of opening (PCV_Reg_lnc) or decreasing the PCV degree of opening (PCV_Reg_Dec), allows the applying of the real-time PCV variation to the real-time PCV value after the outputting of a predetermined number of real-time PCV variations. In other words, the method inputs the real-time error value into the regulator module 314c, applies an increase pause function 316c and a stepper module 324c, and outputs a real-time variation for the frequency setpoint 318b. The method may continue this cycle until the regulator module outputs a zero variation for the inputted real-time input error value.

[0120] Level 1 parameters in this case include CHP_Target, PCV_Reg_Ramp. Level 2 parameters in this case include PCV_Heel and CHP_RD_limit. Level 3 parameters 322a in this case include PCV_Reg_TZ, PCV_Reg_DZ, PCV RU, PCV_RD, PCV_Reg_lnc, PCV_Reg_Dec.

[0121] FIG. 2 displays a well 250a and wellhead 250b equipped with an activation system 244 comprising a gas lift system 244 beneath a flow control valve 242, a gauge 201 and DHSV 204 along liquid production line 246 for oil and water. The gas lift system 244 may comprise gas line 248, an injection gas lift rate (IGR) sensor 232, another flow control valve (FCV) 234, a casing head pressure (CHP) sensor 230, an annulus wing valve (AWV) 236 and a gas-lift pressure (GLP) sensor 238. The line 246 also comprises valves such as a PMV valve 214, PWV 220, AMV 212 and RCV 228. Sensors are also located along the line 246, such as WHT 218, WHP 216, flow line pressure (FLP) 224, liquid flow rate (QTH) 226, ASD 228, and a differential pressure sensor dP 222 through RCV 228. Likewise, the gas line 248 is connected to the well 250a, along which valves such as ASV 202, the other flow control valve (FCV) 234, and W 236 are located. Sensors are also located along the line 248, such as CHP 230, IGR 232 and gas-lift pressure (GLP) 238. A data acquisition line 206 is also depicted to connect gauge 201 to an acquisition unit 208 and BHP sensor 210. FIG. 2 may be used to assist visualizing the implementation of the method as displayed in the example of FIG. 6. Cases 430a, 430b of FIG. 6 and FIG. 7 display implementation of the method for two production target values; one of values 400a (FIG. 6), and value 400b (FIG. 7). In this example, the method implements each case 430a, 430b simultaneously. Considering case 430a, the method determines at function 402a an input error value for each of the five production target values 400 and for each of the two production limit values 440. The error is weighted as a percentage. The operator then selects a user selects production target value 400a from the group of five target production values 400. Upon selecting a desired target production value by the operator at selection step 404, the method determines the lowest input error value at the low pass filter 406. At the low pass filter 406, the method compares the input errors for limits values 440 to the operator-selected production target value 400a. The method then provides a respective regulator module 414a for the provided production target value 402a.

[0122] The providing of the regulator module 414a comprises implementing the production target value 402a, in this case a differential-pressure-on-the-RCV target value (dP_RCV_Target) along with other user-adjustable parameters 410a including the range of the output (i.e. the outputted variation), the minimum RCV opening (Min = RCV_Heel) the maximum ramp up (RU = RCV_Reg_Ramp x RCV_Reg_lnc / RCV_incD) and ramp down (RD = RCV_Reg_Ramp x RCV_Reg_Dec / RCV_decD) of the output (i.e. the outputted variation), the tolerance and damping zones (TZ = RCV_Reg_TZ, DZ = RCV_Reg_DZ) 422a. The regulator module 314a then outputs a variation value for the value of the respective setpoint parameter, RCV setpoint 418a. The method also comprises determining an increase pause function 416a based on conditions 420a that either bottom hole pressure decrease rate being greater than the bottom hole ramp down limit (BHP Dec. Rate > BHP_RD_limit), or on the well head pressure decrease rate being greater than the well head pressure ramp down limit (WHP dec. rate > WHP_RD_Limit). This causes pausing opening the RCV 228 when either condition is fulfilled. As a result, the rate at which the well head pressure decreases can slow. The method also comprises determining a decrease pause function based on condition 426a of the well head pressure increase rate being greater than the well head ramp up limit (WHP Inc. Rate > WHP_RU_Limit). This causes pauses closing the RCV 228 if the condition is fulfilled. As a result, the rate at which the wellhead pressure increases can slow. Following determining the decrease pause function, the method of the example also determines a stepper module 424a to ensure protection of the actuator when applying the setpoint. Upon determining the regulator module 414a, increase pause function 416a, decrease pause function 426a and stepper module 428a, the method once determines a real-time error value corresponding to the input error value, i.e. corresponding to the lowest determined error value by the pass low filter 406. The method inputs the realtime error value into the regulator module 414a and outputs a real-time variation for the RCV setpoint 418a. The increase pause function pauses applying the real-time variation parameter to the real-time (i.e. actual) opening value of the RCV 228 if the condition of the bottom hole pressure decrease rate being greater than the bottom hole ramp down limit is met. The pause may continue until the bottom hole decrease rate reduces. In other words, the method does not implement the pause function if the condition is not met.

[0123] Following the increase pause function, the method implements the decrease pause function if the condition of the WHP increase rate being greater than the WHP ramp up limit is met. In other words, if the condition is not met, the method does not implement the decrease pause function 430a if the condition is not met. The method then implements stepper module 424a. The method can then apply the real-time variation parameter to the real-time (i.e. actual) opening value of the RCV 228. The stepper module 424a may, for an outputted real-time RCV setpoint variation from the regulator module 416a either increasing the RCV degree of opening by multiplying an RCV regulator increment (RCV_Reg_lnc) in percentage (e.g. 1 %) by an RCV delay (RCVJncD), the delay being a duration of time between a first RCV regulator increment and a second RCV regulator increment (e.g. 1 min), decreasing RCV_decD, or decreasing the RCV degree of opening (RCV_Reg_Dec), allows the applying of the real-time PCV variation to the real-time RCV value after the outputting of a predetermined number of real-time RCV variations. The operator may adapt the regulation to be between, for example, 50% and 100% of the ramp speed defined by the level 2 parameters (i.e. RCV_Reg_Ramp and RCV_Reg_Ramp). The method may continue this cycle until the regulator module outputs a zero variation for the inputted real-time input error value.

[0124] Level 1 parameters in this case include RCV_Target, dp_RCV_target, WHT_Target, BHP_Target, Qliq_Target, production target selection, and RCV_Reg_Ramp. Level 2 parameters in this case include WHTJimit, BHPJimit, RCV_Heel, BHP_RD_Limit, WHP_RD_Limit, WHP_RU_Limit, RCV_Reg_lnc, RCVJncD, RCV_Reg_Dec, and RCV_decD. Level 3 parameters 322b in this case include RCV_Reg_TZ and RCV_Reg_DZ.

[0125] Considering case 430b of the example of FIG. 7, the method provides a function 402b an input error value for target value injection gaslift rate (IGR_Target) 400b. The error is weighted as a percentage. The target value 400b being the only provided target value, the method does not determine the lowest input error value at a low pass filter. The method then provides a respective regulator module 414b for the provided production target value 402b.

[0126] The determining of the regulator module 414b comprises implementing the production target value 400b, along with other user-adjustable parameters 410b including the range of the output (i.e. the outputted variation), the minimum injection gaslift rate (Min = IGR_min) the maximum ramp up (Rll = IGR_Reg_Ramp x IGR_Reg_lnc / IGR_incD) and ramp down (RD = IGR_Reg_Ramp x IGR_Reg_Dec / RCV_decD) of the output (i.e. the outputted variation), the tolerance and damping zones (TZ = IGR_Reg_TZ, DZ = IGR_Reg_DZ) 422b. The regulator module 414b then outputs a variation value for the value of the respective setpoint parameter, IGR setpoint 418b for the process control system (PCS) FCV 234 regulation. The method also comprises determining an increase pause function 416b based on the condition 420b that the bottom hole pressure increase rate is greater than the bottom hole ramp down limit (BHP inc. Rate > BHP_RU_limit). This causes pausing opening the RCV 228 when the condition is fulfilled. As a result, the rate at which the bottom hole pressure increases can slow.

[0127] Upon determining the regulator module 414b, increase pause function 416b and stepper module 428b, the method once again determines a real-time error value corresponding to the input error value, i.e. corresponding to the lowest determined error value by the pass low filter 406. The method inputs the real-time error value into the regulator module 414b and outputs a realtime variation for the IGR setpoint 418b. The increase pause function pauses applying the real-time variation parameter to the real-time (i.e. actual) opening value of the FCV 234 if the condition of the bottom hole pressure increase rate being greater than the bottom hole ramp up limit is met. In other words, the method does not implement the pause function if the condition is not met. The pause may continue until the bottom hole pressure increase rate slows until it falls below its limit. Following implementing the increase pause function 420b, the stepper module 428b, for an outputted real-time IGR setpoint variation from the regulator module 416b either increasing the IGR (IGR_Reg_lnc), increasing IGRJncD, decreasing IGR decD, or decreasing the IGR degree of opening (IGR_Reg_Dec), allows the applying of the real-time IGR variation to the real-time IGR value after the outputting of a predetermined number of realtime IGR variations. The method may continue this cycle until the regulator module outputs a zero variation for the inputted real-time input error value.

[0128] Level 1 parameters in this case include IGR_Target and IGV_Reg_Ramp. Level 2 parameters in this case include IGR_min, BHP_RU_Limit, IGR_Reg_lnc, IGRJncD, IGR_Reg_Dec, IGR_decD. Level 3 parameters 322c in this case include IGR_Reg_TZ and IGR_Reg_DZ.

[0129] FIG. 8 displays an example of the function of the regulator module. The function displays ramp, R , as a function of error, e. In other words, the graph displays ramp deduced from error value (e). The ramp may be installed and displayed locally, for example on a display of the system, the display of the system optionally being in a control room. The function is a monotonic function. The function is an increasing function. For each input error value, e, the function outputs a ramp value or variation value. The function is divided into five ranges; a maximum ramp down speed zone 502, a first damping zone 504, tolerance zone 506a, 506b, a second damping zone 508, maximum ramp down speed 510. The maximum ramp down zone 502 defines the range where the function outputs a maximum negative ramp for a range of negative error input values e less than or equal to input error value -DZ. For an error input value e greater than or equal to error value -DZ and less than or equal to -TZ, the function outputs a damping value, i.e. a value within the first damping zone 504. First damping zone 504 is a linear strictly increasing monotonic function. For an error value, e, greater than or equal to error value -TZ and less than or equal to error value TZ, the value -TZ being a negative value and the value TZ being a positive value, the function outputs a value that is said to be within the tolerance zone 506a, 506b and so allows the setpoint to achieve the target value. For an error value e greater than or equal to an error value TZ and less than or equal to an error value DZ, the function outputs a damping value, i.e. a value within the second damping zone 508. Second damping zone 508 is a linear strictly increasing monotonic function. For an error value e greater than or equal to DZ, the function outputs values of the maximum ramp-up speed zone 510.

[0130] FIG. 9 displays an example of implementing the stepper module to performed step by steps actions instead of a continuous variation so as to protect actuator limitations. The figure shows a top graph 600 displaying a curve 616a of measurement selected as a target as a function of time, and a bottom graph 601 displaying a curve 616b RCV as a function of time. Damping zones 606a 606b are defined by line 606c, and also DZ line 602 and TZ line 614 for zone 606a. Tolerance zones 607a, 607b are defined by line 607c and also TZ line 614 and target line 608 for zone 607a. Target line 608 corresponds to the value at which the target value is achieved, i.e. input error is zero. When the error between the measurement used as target and the target parameter is outside of the damping zone, the stepper module applies an increment step 610a (RCV_inc) for every increment delay 612 (RCVJncD). In the damping zone 606, the stepper module applies the increment step 610b (RCV_inc) but with a delay 612b that is longer than the increment delay. In the tolerance zone 606a, 606b the actuator stays in position. The ramp-up and ramp-down speeds may be calculated from the increment’s steps and duration parameters of the stepper module. As a consequence, the regulator output variation cannot be stepper than the speed defined by the level 2 increment’s parameters. In addition, the level 1 parameters RCV_reg_Ramp and IGR_Reg_Ramp allow for a user-friendly way to reduce the reactivity of the regulator down to 50% of the maximum speed defined by the level 2 parameters increment’s parameters.

[0131] FIG. 10 displays an example of the method when the activation system comprises an ESP. Like in figure 5, the regulator module forms a function 700 of five zones, this time of frequency variation (Hz / min) (i.e. motor frequency ramp or variation) as a function of regulator input (%) (i.e. input error); maximum ramp-down, proportional ramp down (i.e. damping), tolerance zone (i.e. the zone has no variation, providing a zero output for a range of error inputs), proportional ramp-up (i.e. damping), and maximum ramp up. The operator sets (unless already predefined) a bottom hole pressure ramp down limit (BHP_RD_Limit) is selected as 1 .0 psi / min. The operator sets an increase pause function for activation at a function slope of 0.0 Hz / min. The operator sets (unless already predefined) a minimum motor frequency to 20.0 Hz, a ramp up motor frequency (MF_RY) to 4.0 Hz / min, and a maximum ramp down frequency (MF_RD) is set to 4.0 Hz / min. An electrical submersible pump regulator tolerance zone (ESP_Reg_TZ) value is set to 1 %. An electrical submersible pump regulator damping zone (ESP_Reg_DZ) value is set to 5%. As can be seen from the figure, a negative input error value, the negative value corresponding to a target value which is too high, the function can output a negative variation value (ramp down). If the error value is less than -5%, the regulator module outputs a variation value of 4.0 Hz / min. If the error value is greater than or equal to -5% and less than 1 %, the regulator module outputs a variation value of less than 4 Hz / min. If the error value is greater than -1 % and less than or equal to 1 %, the regulator module outputs a variation value of 0 Hz / min, the target value being considered to be reached. If the error value greater than or equal to 5%, the regulator module outputs a variation value of 4 Hz / min. If the error value is less than 5% and greater than 1 %, the regulator module outputs a variation value of less than 4.0 Hz / min. If the input error value is a positive error value corresponding to a target value which is too low, the function can output a positive variation value (ramp up). The regulator module may consequently apply a real-time variation of 38.5 Hz (also referred to as a tolerance value) to the real-time value of the respective setpoint parameter.

[0132] FIG. 11 displays an example applying the variation to the real-time value of the respective setpoint parameter for the case where the activation system comprises an ESP, the graph showing the variation of a production parameter as a function of time. The graph displays the curve 800 with damping and the curve 802 without damping approaching the target value 806 from the initial value 804. The curve 802 without damping approaches the target value more abruptly than the curve 800 with damping. As a result of this more gradual approach, sudden stopping of the ramp up or ramp down can be avoided and hence any resulting damage to well or well components.

[0133] FIG. 12A also displays the example of FIG. 11 . The graph displays the variation of a setpoint parameter value (in this case, a valve or choke opening value) as a function of time. The figure shows an example of the stepper module applying step by step actions for curve 900, as opposed to the continuous variations observed in curve 902. For curve 900, as the value approaches the target value and enters into the damping zone 908, the stepper module increases the duration between each choke action (i.e. each change in valve opening).

[0134] FIG. 12B also displays the example of FIG. 11 . The graph displays the variation of a setpoint parameter value as a function of time (as in FIG. 12A, in this case, a valve or choke opening value). The zoomed section 912 provides a close up of the target tolerance zone 910, where it can be seen that, once the curve 900 enters the tolerance zone, it stops approaching the target value. No more actions are taken when the value is inside the defined target tolerance zone.

[0135] FIG. 13 provides an example of a user interface with the system for performing the method. The interface includes state status 10, indicating the status of production, and a sub-state status 12, indicating production regulation. The interface also comprises an optimization timer 14, deactivate button 20, FCW stop button 22 and message interface 24. For the ESP case, the interface may allow for the operator to select the production target and adjust the production target values (for example, MF_target value or WHT_target value or BHP_target value). It may also allow the operator to check the limiter states. The operator may also, through the interface, damper the RCV movements by adjusting the RCV_Reg_Ramp parameters between, for example, 0.5 and 1 .0. Regarding the regulator module, it may manage the pump frequency set point according to the selected target value and the active limitations. RCV regulation may also be active. As a result, the method may regulate WHP to the WHP_target value.

Claims

CLAIMS1 . A computer-implemented method for control of a hydrocarbon production well equipped with an artificial activation system, the artificial activation system comprising either a gas lift system or an electrical submersible pump (ESP), the method comprising:- providing one or more target values each of a respective production parameter and each corresponding to a respective setpoint parameter, each setpoint parameter being an operating parameter of the hydrocarbon production well, at least one target value corresponding to a respective setpoint parameter which is an operating parameter of the artificial activation system; and- for each setpoint parameter: o providing a respective regulator module, the regulator module being a monotonic function that outputs, for an input error value respective to the setpoint parameter, a variation of value for the respective setpoint parameter, the function outputting a zero variation when the input error value is zero, the function being strictly monotonic for a first range of input error values, the input error values of the first range being negative, the function further being strictly monotonic for a second range of input error values, the input error values of the second range being positive; and o repeatedly:■ determining a real-time target error value for the target value corresponding to the setpoint parameter;■ determining a real-time input error value respective to the setpoint parameter based on the real-time target error value;■ inputting the real-time input error value into the respective regulator module, thereby outputting a real-time variation of value for the respective setpoint parameter; and■ applying the real-time variation to the real-time value of the respective setpoint parameter.

2. The method according to claim 1 , wherein the function outputs a zero variation for a third range of input error values, the third range including the input error value which is zero.

3. The method according to claim 1 or 2, wherein the function is constant before the first range and after the second range.

4. The method according to claim 3, wherein the function includes:- a maximum ramp-down zone corresponding to the function being constant before the first range, the input error values being lower than a first negative threshold (-DZ) and the output variation being constant in said maximum ramp-down zone;- a first damping zone corresponding to the first range of input error values, the input error values being higher than the first negative threshold (-DZ) but lower than a second negative threshold (-TZ) and the output variation being strictly monotonic in said first damping zone;- a tolerance zone corresponding to the third range of input error values, the input error values being higher than the second negative threshold (-TZ) but lower than a first positive threshold (TZ) and the output variation having a zero variation;- a second damping zone corresponding to the second range of input error values, the input error values being higher than the first positive threshold (TZ) but lower than a second positive threshold (DZ) and the output variation being strictly monotonic in said second damping zone;- a maximum ramp-up speed zone corresponding to the function being constant after the second range, the input error values being higher than the second positive threshold (DZ) and the output variation being constant in said maximum ramp-up zone.

5. The method according to any one of claims 1 to 4, wherein for at least one setpoint parameter, the determining of the real-time input error value respective to the at least one setpoint parameter comprises at each repetition:- determining one or more real-time limit error values each for a respective limit value of a production or operating parameter corresponding to the at least one setpoint parameter;- selecting a lowest error value amongst the real-time target error value and the one or more real-time limit error values;- using the lowest error value as the real-time input error value; and / or for at least one other setpoint parameter, the determining of the real-time input error value respective to the at least one other setpoint parameter comprises at each repetition:- using the real-time target error value as the real-time input error value.

6. The method according to claim 5, wherein each real-time target error value is a weighted difference between the target value of the corresponding production parameter and the effective real-time value of the corresponding production parameter, and / or each real-time limit error value is a weighted difference between the respective limit value and the effective real-time value of the respective production or operating parameter.

7. The method according to any one of claims 1 to 6, wherein the respective setpoint parameter is a remote control valve (RCV) setpoint parameter.

8. The method according to anyone of claims 1 to 7, wherein the method further comprises repeatedly implementing a respective increase pause function, the function being a safety measure that pauses applying the realtime variation to the real-time value when a parameter value associated with the setpoint parameter reaches a respective critical measurement variation limit.

9. The method according to claim 8, wherein the respective critical measurement variation limit is a bottom hole pressure decrease rate.

10. The method according to claim 8, wherein, for the case of the artificial activation system comprising a gas lift system, the respective critical measurement variation limit is either a bottom hole pressure decrease rate or a wellhead pressure decrease rate.

11. The method according to any one of claims 7 to 10, wherein pausing applying the real-time variation to the real-time value comprises pausing opening the RCV.

12. The method according to any one of claims 1 to 11 , wherein, for the case of the artificial activation system comprising a gas lift system, the respective setpoint parameter is a injection gas rate setpoint parameter.

13. The method according to claim 12, wherein pausing applying the realtime variation to the real-time value comprises pausing a gas injection.

14. The method according to any one of claims 1 to 13, wherein, for the case of the artificial activation system comprising an ESP, the respective setpoint parameter is a pressure control valve (PCV) setpoint parameter.

15. The method according to claim 14, wherein pausing applying the realtime variation to the real-time value comprises pausing opening the PCV.

16. The method according to any one of claims 8 to 15, wherein the method further comprises, for the case of the artificial activation system comprising a gas lift system, repeatedly implementing a respective decrease pause function after the increase function, the function being a safety measure that pauses applying the real-time variation to the real-time value according to another respective critical measurement variation limit.

17. The method according to claim 16, wherein pausing applying the realtime variation to the real-time value comprises pausing closing the RCV.

18. The method according to anyone of claims 1 to 17, wherein, for case of the artificial activation system comprising an ESP, the respective setpoint parameter is a frequency setpoint parameter of the ESP.

19. The method according to claim 18, wherein, for the case of the artificial activation system comprising an ESP, pausing applying the real-time variation to the real-time value comprises pausing increasing the ESP frequency.

20. The method according to anyone of claims 1 to 19, wherein the method further comprises implementing a stepper module which, after the outputting of a predetermined number of real-time variations, allows the applying of the real-time variation to the real-time value.21 . The method according to any one of claims 1 to 20, wherein, for the case of the artificial activation system comprising an ESP, the one or more production target values are selected from motor frequency, well head temperature (MF), bottom hole pressure (BHP), well head pressure (WHP), liquid flow rate (Qliq), and / or casing head pressure (CHP).

22. The method according to any one of claims 1 to 21 , wherein, for the case of the artificial activation system comprising a gas lift system, the one or more target values are selected from RCV degree of opening, RCV differential pressure (dP_RCV), liquid flow rate, well head pressure, bottom hole pressure and / or injection gas lift rate (IGR).

23. The method according to any one of claims 1 to 22, wherein, for the case of the artificial activation system comprising an ESP, the one or more limit values include bottom hole pressure, well head pressure and / or motor current (MC).

24. The method according to any one of claims 1 to 23, wherein, for the case of the artificial activation system comprising a gas lift system, the one or more limit values include bottom hole pressure and / or well head pressure.

25. The method according to anyone of claims 1 to 24, wherein at least one target value is user-selected among at least two possibilities corresponding to the same respective setpoint parameter, for example, three of the target values, or five of the target values.

26. The method according to anyone of claims 1 to 25, wherein the respective regulator module comprises at least one constraint to assist in the outputting of the respective value of the respective setpoint parameter, for example a range of an output, a maximum ramp up speed of the output, and / or maximum ramp down speed of the output.

27. The method according to claim 26, wherein a value of the at least one constraint is a user-adjusted value.

28. The method according to claim 26 or 27, wherein another value of the at least one constraint is a predetermined value.

29. A computer program comprising instructions which, when executed by a processor, cause the processor to perform the method of any one of claims 1 to 28.

30. A data storage medium having recorded thereon a computer program according to claim 29.31 . A system for control of a hydrocarbon production well equipped with an artificial activation system, the artificial activation system comprising either a gas lift system or an ESP, the system comprising:- a memory having recorded thereon a computer program according to claim 29; and- a processor for executing the program.

32. Equipment for a hydrocarbon production well, the equipment including an artificial activation system, the artificial activation system comprising either a gas lift system or an ESP, the equipment further including a system according to claim 31 .

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