Ppid control system and method based on intelligent judgment of control deviation

Abstract

The application discloses a PID control system and method based on control deviation intelligent judgment, belongs to the technical field of PID control, and solves the problem that the existing thermal power unit control system can only select one type of PID, and the single type of PID cannot guarantee reasonable adjustment of the system while shortening the service life of an executing mechanism and maintaining the stability of the system. A dead zone module is used to judge the stability of a PID set value and a PID process value and the stability of a change rate of the PID set value and a change rate of the PID process value; a lock-in increase module is used to judge whether the difference between the PID set value and the PID process value is positive; if not, a lock-in decrease module is executed; if yes, when the change rate of the PID process value in the increasing direction is lower than a certain value, the lock-in increase module is executed; the lock-in decrease module is used to judge whether the difference between the PID set value and the PID process value is negative; if not, the lock-in increase module is executed; and when the change rate of the PID process value in the decreasing direction is lower than a certain value, the lock-in decrease module is executed.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of PID control, and particularly relates to a PID control system based on intelligent judgment of control deviation. BACKGROUND

[0002] The conventional PID (abbreviation of proportion, integral and differential) closed-loop control is a control mode of correcting according to the output feedback of a control object, which is to correct according to a quota or a standard when the actual value deviates from the planned value. For example, to control the rotating speed of an electric motor, a sensor for measuring the rotating speed is needed, and the result is fed back to the control route. The conventional PID is generally divided into two modes, the first mode is a position type PID module, and the second mode is an incremental type PID module.

[0003] The design, debugging and optimization of the conventional thermal power unit control system are usually for the interval above 50% rated load, and less for the low load operation condition. When the unit is operated at ultra-low load, the control object characteristics of the unit change greatly. At low load, the fuel quantity and the feed water flow corresponding to the load are low, and the variable load disturbance is relatively large. In addition, the boiler efficiency is low at low load, and the fuel quantity changes more greatly with the increase or decrease of 10 MW load, which is more likely to cause fluctuations of the main steam pressure and temperature. The automatic control of the conventional PID only relies on the deviation change of proportion, integral and differential, and often cannot meet the safe and stable operation requirements of the automatic control system at low load, and in serious cases, it may lead to unstable boiler combustion, unit shutdown and other serious problems. In addition, when the position type PID module is selected for the electric unit control system at low load, the control deviation is too large, which often leads to the regulation lag of the automatic control system, and thus the coupling oscillation of the control parameters and the actuator. When the incremental type PID module is selected for the thermal power unit control system at low load, the controller is frequently adjusted when a small control deviation exists, which causes system fluctuations.

[0004] In summary, the existing thermal power unit control system at low load can only select one type of PID. When the position type PID module is selected, the regulation lag of the thermal power unit control system at low load occurs when the control deviation is too large. When the incremental type PID module is selected, the reciprocating regulation of the thermal power unit control system at low load occurs when the control deviation is too small, which not only causes the instability of the thermal power unit control system at low load, but also affects the service life of the actuator. SUMMARY

[0005] The present application solves the problem that the existing thermal power unit control system can only select one type of PID, and the single type of PID cannot guarantee the reasonable regulation of the system while not shortening the service life of the actuator and maintaining the stability of the system.

[0006] The PID control system based on control deviation intelligent judgment comprises a dead zone module, a lock-in increase module and a lock-in decrease module.

[0007] The dead zone module judges the stability of the PID set value and the PID process value, and the stability of the change rate of the PID set value and the change rate of the PID process value.

[0008] The lock-in increase module judges whether the difference between the PID set value and the PID process value is positive, if not, the lock-in decrease module is executed, if yes, when the change rate of the PID process value in the increasing direction is lower than a certain value, the lock-in increase module is executed.

[0009] The lock-in decrease module judges whether the difference between the PID set value and the PID process value is negative, if not, the lock-in increase module is executed, when the change rate of the PID process value in the decreasing direction is lower than a certain value, the lock-in decrease module is executed.

[0010] Further, in an embodiment of the present application, the dead zone module comprises a first dead zone module and a second dead zone module.

[0011] The first dead zone module judges whether the PID set value and the PID process value tend to be stable, if yes, the first dead zone module is executed, if not, the first dead zone module is cancelled.

[0012] The second dead zone module judges whether the change rate of the PID set value and the change rate of the PID process value tend to be stable, if yes, the second dead zone module is executed, if not, the second dead zone module is cancelled.

[0013] Further, in an embodiment of the present application, the condition that the PID set value and the PID process value tend to be stable is that:

[0014] The PID set value is equal to the PID process value, or the PID set value is approximately equal to the PID process value.

[0015] Further, in an embodiment of the present application, the condition that the change rate of the PID set value and the change rate of the PID process value tend to be stable is that:

[0016] The change rate of the PID set value is equal to the change rate of the PID process value, or the change rate of the PID set value is approximately equal to the change rate of the PID process value.

[0017] Further, in an embodiment of the present application, the lock-in increase module and the lock-in decrease module are both based on an incremental PID module combined with a positional PID module.

[0018] The PID control method based on intelligent judgment of control deviation is implemented by the PID control system based on intelligent judgment of control deviation, and comprises the following steps.

[0019] In step S1, it is judged whether the PID set value and the PID process value tend to be stable, if yes, the first dead zone function is executed, and then step S2 is executed, if not, the first dead zone function is cancelled, and then step S2 is executed.

[0020] In step S2, it is judged whether the change rate of the PID set value and the change rate of the PID process value tend to be stable, if yes, the second dead zone function is executed, and then step S3 is executed, if not, the second dead zone function is cancelled, and then step S3 is executed.

[0021] In step S3, it is judged whether the difference between the PID set value and the PID process value is positive, if not, step S4 is executed, if yes, when the change rate of the PID process value in the increasing direction is lower than a certain value, the lock-increase is executed, and the operation is ended.

[0022] In step S4, when the change rate of the PID process value in the decreasing direction is lower than a certain value, the lock-decrease is executed, and the operation is ended.

[0023] The electronic device comprises a processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory complete mutual communication through the communication bus.

[0024] The memory is used for storing a computer program.

[0025] The processor is used for executing the program stored on the memory, and realizes the method steps in the above method.

[0026] The computer readable storage medium stores a computer program, and the computer program is executed by the processor to realize the method steps in the above method.

[0027] The present application solves the problem that the existing thermal power unit control system can only select one type of PID, and the single type of PID cannot guarantee the reasonable adjustment of the system while not shortening the service life of the actuator and maintaining the stability of the system.

[0028] 1. The PID control system based on intelligent judgment of control deviation, the existing thermal power unit control system has the problem of being able to only select one type of PID, the application takes the incremental PID module as the basis, combines the position type PID module, and twice takes the PID set value and the PID process value, the change rate of the PID set value and the change rate of the PID process value as the judgment basis, realizes the integration of the advantages of the incremental PID module and the position type PID module, and avoids the disadvantages, the integrated PID module can be applied to the thermal power unit control system;

[0029] 2. The PID control system based on intelligent judgment of control deviation, the existing position type PID only adjusts the thermal power machine control system when the control deviation is too large, which causes the adjustment lag, the control deviation of the existing incremental PID module is small and the change amplitude is not large, which also causes frequent fluctuations in the small opening range, further aggravating the fluctuation of the thermal power unit control system, which is not conducive to the stability of the thermal power unit control system under low load working conditions. The application sets the dead zone module, the lock-increase module and the lock-decrease module, first, according to the stability of the control deviation and the change rate of the control deviation, the dead zone module is reasonably set, so that small control deviation or control deviation with slow change rate will not disturb the thermal power unit control system, and when large control deviation or control deviation with fast change rate appears, the dead zone module can be directly cancelled for rapid adjustment, therefore, the dead zone module reduces the reciprocating swing of the process value and the controller output, prolongs the service life of the actuator, thereby maintaining the stability of the thermal power unit control system, especially providing higher protection for the stability and safety of the thermal power unit control system under low load operating conditions. Secondly, through the judgment of the size of the control deviation and the change rate of the control deviation by the lock-increase module and the lock-decrease module, the appropriate process value is set to ensure the rationality of the adjustment, solve the problem of adjustment lag of the position type PID module for the thermal power unit control system, and also simulate the operation mode of the operator, more intelligently adjust the actuator, and also reduce the number of actions of the actuator, prolong the service life of the actuator;

[0030] In summary, the application combines the dead zone module, the lock-increase module and the lock-decrease module, for a single type of PID, not only ensures the reasonable adjustment of the thermal power unit control system, but also prolongs the service life of the actuator, and maintains the stability of the thermal power unit control system;

[0031] The PID control system based on intelligent judgment of control deviation can be applied to the thermal power unit control system under all working conditions. BRIEF DESCRIPTION OF DRAWINGS

[0032] The above and / or additional aspects and advantages of the present application will become apparent and more readily appreciated from the following description, taken in conjunction with the following drawings of which:

[0033] Figure 1 is a PID control bias input "dead zone intelligent selection" diagram according to the first embodiment;

[0034] Figure 2 is a PID lock-increase control logic diagram based on control bias and change rate according to the first embodiment;

[0035] Figure 3 is a PID lock-decrease control logic diagram based on control bias and change rate according to the first embodiment. DETAILED DESCRIPTION

[0036] Various embodiments of the present application will be described in detail below with reference to the drawings. The embodiments described by reference to the drawings are exemplary and are intended to explain the present application, and should not be understood as limiting the present application.

[0037] The PID control system based on control bias intelligent judgment according to the first embodiment includes a dead zone module, a lock-increase module, and a lock-decrease module.

[0038] The dead zone module judges the stability of the PID set value and the PID process value, and the stability of the change rate of the PID set value and the change rate of the PID process value.

[0039] The lock-increase module judges whether the difference between the PID set value and the PID process value is positive, and if not, executes the lock-decrease module, and if yes, executes the lock-increase module when the change rate of the PID process value in the increasing direction is lower than a certain value.

[0040] The lock-decrease module judges whether the difference between the PID set value and the PID process value is negative, and if not, executes the lock-increase module, and when the change rate of the PID process value in the decreasing direction is lower than a certain value, executes the lock-decrease module.

[0041] In the present embodiment, the dead zone module includes a first dead zone module and a second dead zone module.

[0042] The first dead zone module judges whether the PID set value and the PID process value tend to be stable, and if yes, executes the first dead zone module, and if not, cancels the first dead zone module.

[0043] The second dead zone module judges whether the change rate of the PID set value and the change rate of the PID process value tend to be stable, and if yes, executes the second dead zone module, and if not, cancels the second dead zone module.

[0044] In the embodiment, the condition for the PID set value and the PID process value to tend to be stable is that:

[0045] The PID set value is equal to the PID process value, or the PID set value is approximately equal to the PID process value.

[0046] In the embodiment, the condition for the change rate of the PID set value and the change rate of the PID process value to tend to be stable is that:

[0047] The change rate of the PID set value is equal to the change rate of the PID process value, or the change rate of the PID set value is approximately equal to the change rate of the PID process value.

[0048] In the embodiment, the lock-in increment module and the lock-in decrement module are both based on an increment type PID module and combined with a position type PID module.

[0049] In the embodiment, in the step S1, the sealing strip is located at the center position of the pressure sensor.

[0050] The design, debugging and optimization of the existing thermal power unit control system are usually for the interval above 50% rated load, and less involve the thermal power unit control system under low load operation condition;

[0051] Based on the above problems, the PID control system for intelligent judgment of control deviation provided in the embodiment is mainly for the thermal power unit control system under low load operation condition, and the PID control system can also be applied to the thermal power unit control system under operation condition above 50% rated load.

[0052] However, for the thermal power unit control system under any condition, only one type of PID can be selected at present, that is, a position type PID module or an increment type PID module is selected;

[0053] When the position type PID module is selected, adjustment is only performed when the process value exceeds the set value or the process value is less than the set value, and there is no prediction function. When the process value approaches the set value at a faster speed, the adjustment is lagged, the control effect is not ideal, and the automatic control parameters are often coupled with the actuator to cause oscillation;

[0054] When the increment type PID module is selected, when the control deviation is large, the actuator is often excessively adjusted due to too much advanced adjustment;

[0055] For example, in the automatic control system of low-pressure heater liquid level, the automatic control of low-pressure heater liquid level is controlled by normal drainage control valve and emergency drainage control valve, the water level set value of emergency drainage control valve is higher than that of normal drainage control valve. But when the unit load or system operating condition changes, the water level will fluctuate, when the emergency drainage control valve selects the position type PID model, the valve will only act when the water level reaches the set value, which will lead to the lag of the regulation effect and the large rise of the water level, which is not conducive to the stability of the water level, when the emergency drainage control valve selects the incremental type PID model, the emergency drainage control valve will fluctuate frequently in the range of small opening degree, which further aggravates the fluctuation of the water level.

[0056] Therefore, the current single type of PID cannot guarantee the reasonable regulation of the thermal power unit control system while not shortening the service life of the actuator and maintaining the stability of the system.

[0057] In the embodiment, based on the incremental type PID module, the position type PID module is combined, the set value is reasonably set, the control deviation and the control deviation are used as the judgment basis, the advantages of the two types of PID are integrated, and the disadvantages are avoided.

[0058] Specifically, as shown in the figure, the PID control system includes a dead zone module, a lock-increase module and a lock-decrease module. Figure 1

[0059] The dead zone module includes a first dead zone module, a second dead zone module, a first PID set value module, a first PID process value module, a first subtraction module, a lead-lag module, a function generator module, a selection switching module, a first AND module, a constant module and a PID module.

[0060] The first PID set value module and the first PID process value module transmit signals to the first subtraction module.

[0061] The first subtraction module transmits signals to the lead-lag module, the first dead zone module and the second dead zone module.

[0062] The first dead zone module and the second dead zone module transmit signals to the AND module.

[0063] The first AND module transmits signals to the selection switching module.

[0064] The selection switching module transmits signals to the PID module.

[0065] The lead-lag module transmits signals to the function generator module or the selection switching module.

[0066] The function generator module transmits signals to the selection switching module.​

[0067] The selection switching module transmits a signal to the PID module;

[0068] The constant module transmits a signal to the PID module;

[0069] The first dead zone module comprises a first absolute value module and a first low value judgment module;

[0070] The first absolute value module transmits a signal to the first low value judgment module;

[0071] The second dead zone module comprises a first analog quantity pure lag module, a second subtraction module, a second absolute value module and a second low value judgment module;

[0072] The first analog quantity pure lag module transmits a signal to the second subtraction module;

[0073] The second subtraction module transmits a signal to the second absolute value module;

[0074] The second absolute value module transmits a signal to the second low value judgment module;

[0075] Through the construction of the dead zone module, the lock-increase module and the lock-decrease module, the lock-increase module is connected to the lock-increase pin of the incremental PID module, the lock-decrease module is connected to the lock-decrease pin of the incremental PID module, and the dead zone module is selected to control the deviation and is connected to the input position of the incremental PID module, so as to realize the intelligent adjustment of the PID and also to assist in correcting the rationality of the proportional and integral parameters.

[0076] The first dead zone module judges whether the PID set value is equal to the PID process value or whether the PID set value is approximately equal to the PID process value, that is, the control deviation of the PID set value and the PID process value is small, if yes, the first dead zone module is executed, then the second dead zone module is executed, so that the small control deviation does not disturb the PID control system, if no, the first dead zone module is cancelled, so that when the large control deviation occurs, the thermal power unit control system can be quickly adjusted;

[0077] The second dead zone module judges whether the change rate of the PID set value is equal to the change rate of the PID process value or whether the change rate of the PID set value is approximately equal to the change rate of the PID process value, that is, the change rate of the control deviation of the change rate of the PID set value and the change rate of the PID process value is small, if yes, the second dead zone module is executed, then the lock-increase module is executed, so that the small change rate of the control deviation does not disturb the PID control system, if no, the second dead zone module is cancelled, so that when the large change rate of the control deviation occurs, the thermal power unit control system can be quickly adjusted;

[0078] The setting of the PID process value of the dead zone module and the setting of the change rate of the PID process value are set reasonably according to different control systems and the control precision requirements of the operating personnel on the control parameters. For example, for the main steam and reheat steam temperature control system, the PID process value of the dead zone module can be set to ±1℃, and the change rate of the PID process value can be set to ±2℃ / min; for the main steam pressure control system, the PID process value of the dead zone module can be set to ±0.1MPa, and the change rate of the PID process value can be set to 0.05MPa / min;

[0079] That is, the dead zone module intelligently judges the control deviation, and intelligently selects the timing of the action of the dead zone module according to the stability of the control deviation and the change rate of the control deviation, so as to ensure the stability of the output of the thermal power unit control system and keep the PID process value or the change rate of the PID process value within a small range. For example, the main steam pressure has a small fluctuation even if the boiler combustion is very stable, at this time, it is considered to be a stable working condition, and the change of the coal output of the boiler main control does not need to be adjusted. At the same time, when the PID process value changes greatly or the change rate of the PID process value is fast, the dead zone module is cancelled to ensure the speed of the regulator output;

[0080] Therefore, the dead zone module can reduce the reciprocating swing of the PID process value and the controller output, prolong the service life of the actuator, reduce the disturbance to the thermal power unit control system, improve the stability of the equipment, the system and the unit operation, especially the stability and safety of the unit low load operation condition, and solve the problem that the existing incremental PID module is too advanced to adjust, which shortens the service life of the actuator and affects the stability of the thermal power unit control system.

[0081] As shown in Figure 2 The lock-in module includes a second PID set value module, a second PID process value module, a first summation module, a second analog quantity pure lag module, a second summation module, a first high value judgment module, a third low value judgment module, a second AND module and a lock-in output module.

[0082] When the lock-in module judges that the difference between the PID set value and the PID process value is positive, the execution process is as follows: the second PID set value module and the second PID process value module transmit signals to the first summation module;

[0083] The first summation module transmits signals to the first high value judgment module;

[0084] The first high value judgment module transmits signals to the second AND module;

[0085] The second and module transmits signals to the lock-increase output module;

[0086] The lock-increase module, when the change rate of the PID process value in the increasing direction is lower than a certain value, executes the process that the second PID set value module and the second analog quantity pure lag module transmit signals to the second summation module;

[0087] The second summation module transmits signals to the third low value judgment module;

[0088] The third low value judgment module transmits signals to the second and module;

[0089] The second and module transmits signals to the lock-increase output module.

[0090] After the execution of the dead zone module, the lock-increase module is executed to judge the first criterion, for example, the main steam temperature, that is, when PID set value-PID process value>10℃, it is indicated that the PID process value is far away from the PID set value; when the first criterion condition is met, whether the change rate of the PID process value in the increasing direction is lower than a certain value is judged, for example, the temperature increasing speed is less than 1℃ / min per minute, it is considered that the PID process value is far away from the PID set value, and the change rate of the PID process value is slow, at this time, the actuator does not continue to open. The judgment process not only can ensure the stable increase of the PID process value, but also is beneficial to the stability of the thermal power unit control system and the service life of the actuator;

[0091] The setting of the PID process value of the lock-increase module and the change rate of the PID process value is reasonably set according to different control systems and the control precision requirements of the running personnel on the control parameters.

[0092] As shown in Figure 3 The lock-decrease module includes a third PID set value module, a third PID process value module, a third summation module, a third analog quantity pure lag module, a fourth summation module, a second high value judgment module, a fourth low value judgment module, a third and module and a lock-decrease output module;

[0093] The lock-increase module, when the difference between the PID set value and the PID process value is negative, executes the process that the third PID set value module and the third PID process value module transmit signals to the third summation module;

[0094] The fourth summation module transmits signals to the fourth low value judgment module;

[0095] The fourth low value judgment module transmits signals to the third and module;

[0096] The third AND module transmits signals to the lock-increase output module;

[0097] The third PID process value module and the third analog quantity pure lag module transmit signals to the fourth summation module when the change rate of the PID process value in the decreasing direction is lower than a certain value;

[0098] The fourth summation module transmits signals to the second high value judgment module;

[0099] The second high value judgment module transmits signals to the third AND module;

[0100] The third AND module transmits signals to the lock-increase output module.

[0101] If the first criterion condition of the lock-increase module is not met, the lock-decrease module is executed. Taking the main steam temperature as an example, the second criterion is judged, i.e., when the PID set value-PID process value is less than -10℃, it is indicated that the PID process value is far away from the PID set value. When the second criterion is met, if the change rate of the PID process value in the decreasing direction is lower than a certain value, for example, the temperature decreasing speed is less than 1℃ / min per minute, it is considered that the PID process value is far away from the PID set value, and the change rate of the PID process value is slow. At this time, the actuator does not continue to close. This judgment process not only can ensure the stable increase of the PID process value, but also is beneficial to the stability of the thermal power unit control system and the service life of the actuator;

[0102] The setting of the PID process value of the lock-increase module and the change rate of the PID process value is reasonably set according to different control systems and the control precision requirements of the control parameters of the operating personnel.

[0103] By judging the size of the control deviation and the change rate of the control deviation through the lock-increase module and the lock-decrease module, setting appropriate criterion values, and assisting the proportional and integral parameters of the PID to adjust the thermal power unit control system, the rationality of the adjustment can be ensured, the problem of the existing position type PID module adjustment lag is solved, the operation mode of the operating personnel is imitated, the actuator is more intelligently adjusted, the number of actions of the actuator is reduced, and the service life of the actuator is prolonged.

[0104] Embodiment two, the PID control method based on intelligent judgment of control deviation is implemented by the PID control system based on intelligent judgment of control deviation in the embodiment one, and includes the following steps:

[0105] Step S1, judging whether the PID set value and the PID process value tend to be stable, if yes, executing the first dead zone function, then executing step S2, if not, canceling the first dead zone function, then executing step S2;

[0106] Step S2, judging whether the change rate of the PID set value and the change rate of the PID process value tend to be stable, if yes, executing the second dead zone function, then executing step S3, if not, canceling the second dead zone function, then executing step S3;

[0107] Step S3, judging whether the difference between the PID set value and the PID process value is positive, if not, executing step S4, if yes, when the change rate of the PID process value in the increasing direction is lower than a certain value, executing the lock-increase, then ending the operation;

[0108] Step S4, when the change rate of the PID process value in the decreasing direction is lower than a certain value, executing the lock-decrease, then ending the operation.

[0109] The PID control system and method based on intelligent control deviation judgment are described in detail above, and the principle and implementation mode of the present application are described by using specific examples; the above examples are only used to help understand the method and core idea of the present application; meanwhile, for the general technical personnel in the field, the specific implementation mode and application range will be changed according to the idea of the present application, and the above description should not be understood as the limitation of the present application.

Claims

1. A PID control system based on intelligent judgment of control deviation, characterized in that, The PID control system comprises a dead zone module, a lock-in increase module and a lock-in decrease module. The dead zone module judges the stability of the PID set value and the PID process value, and the stability of the change rate of the PID set value and the change rate of the PID process value. The lock-in increase module judges whether the difference between the PID set value and the PID process value is positive, if not, the lock-in decrease module is executed, if yes, when the change rate of the PID process value in the increasing direction is lower than a certain value, the lock-in increase module is executed. The lock-in decrease module judges whether the difference between the PID set value and the PID process value is negative, if not, the lock-in increase module is executed, when the change rate of the PID process value in the decreasing direction is lower than a certain value, the lock-in decrease module is executed. The dead zone module comprises a first dead zone module and a second dead zone module.

2. The PID control system based on intelligent judgment of control deviation according to claim 1, characterized in that, The first dead zone module judges whether the PID set value and the PID process value are equal or approximately equal, if yes, the first dead zone module is executed, and then the second dead zone module is executed, if not, the first dead zone module is cancelled. The second dead zone module judges whether the change rate of the PID set value and the change rate of the PID process value are equal or approximately equal, if yes, the second dead zone module is executed, and then the lock-in increase module is executed, if not, the second dead zone module is cancelled. The condition that the PID set value and the PID process value tend to be stable is that the PID set value is equal to the PID process value or the PID set value is approximately equal to the PID process value.

3. The PID control system based on intelligent judgment of control deviation according to claim 1, characterized in that, The condition that the change rate of the PID set value and the change rate of the PID process value tend to be stable is that the change rate of the PID set value is equal to the change rate of the PID process value or the change rate of the PID set value is approximately equal to the change rate of the PID process value. The lock-in increase module and the lock-in decrease module are based on the incremental PID module and combined with the positional PID module.

4. The PID control system based on intelligent judgment of control deviation according to claim 1, characterized in that, The method comprises the following steps: Step S1, judging whether the PID set value and the PID process value tend to be stable, if yes, the first dead zone function is executed, and then step S2 is executed, if not, the first dead zone function is cancelled, and then step S2 is executed.

5. The PID control system based on intelligent judgment of control deviation according to claim 1, characterized in that, Step S2, judging whether the change rate of the PID set value and the change rate of the PID process value tend to be stable, if yes, the second dead zone function is executed, and then step S3 is executed, if not, the second dead zone function is cancelled, and then step S3 is executed.

6. The PID control method based on intelligent judgment of control deviation, which is implemented by the PID control system based on intelligent judgment of control deviation according to any one of claims 1-5, characterized in that, ​ ​ ​ Step S3, judging whether the difference between the PID set value and the PID process value is positive, if not, executing step S4, if yes, executing the lock-increase after the change rate of the PID process value in the increasing direction is lower than a certain value, ending the operation; Step S4, executing the lock-decrease after the change rate of the PID process value in the decreasing direction is lower than a certain value, ending the operation; The condition for the PID set value and the PID process value to tend to be stable is that: The PID set value is equal to the PID process value, or the PID set value is approximately equal to the PID process value; The condition for the change rate of the PID set value and the change rate of the PID process value to tend to be stable is that: The change rate of the PID set value is equal to the change rate of the PID process value, or the change rate of the PID set value is approximately equal to the change rate of the PID process value.

7. An electronic device, comprising: The computer readable storage medium stores a computer program, and the computer program is executed by the processor to realize the method steps in claim 6. The computer readable storage medium stores a computer program, and the computer program is executed by the processor to realize the method steps in claim 6. ​ 8. A computer-readable storage medium, characterized in that, ​

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