CN106594793A - Outlet temperature control optimizing method of medium-speed coal pulverizer of thermal power generating unit - Google Patents

Abstract

The invention relates to a method for optimizing the outlet temperature control of a medium-speed coal pulverizer of a thermal power unit. A PID regulator is added to the DCS control logic configuration of the thermal power unit distributed control system, and a chain link is added to the thermal power unit distributed control system DCS control logic configuration. Control logic; in the control logic primary air pressure control loop configuration of the DCS of the thermal power unit distributed control system, the primary air pressure setting value correction value control loop interface based on the medium-speed coal mill outlet temperature control optimization is added, and the primary air pressure setting The fixed value correction value interlocking control logic output is introduced into the primary air pressure set value correction value control loop interface based on the medium-speed coal mill outlet temperature control optimization, as the primary air pressure control correction value; the control system is put into actual operation, according to the real-time operation Curve, on-line adjustment of thermal power unit medium-speed coal mill outlet temperature control parameters of each control loop, to achieve the desired effect. The real-time performance is good, the on-site debugging process is simple, and it is convenient for engineering realization.

Description

Optimal method for outlet temperature control of medium-speed pulverizers in thermal power units

technical field

The invention belongs to the technical field of automatic control of thermal power generating sets, and in particular relates to a method for controlling and optimizing the outlet temperature of a medium-speed coal pulverizer of a thermal power generating set. It can be used to automatically control the outlet temperature of the medium-speed coal mill during the actual operation of the thermal power unit to ensure that the outlet temperature of the medium-speed coal mill is automatically controlled within a reasonable range during the operation of the unit.

Background technique

During the actual operation of thermal power units, there are often problems such as variable coal types ground by the medium-speed coal mill and inaccurate measurement of the primary air volume at the inlet of the medium-speed coal mill, resulting in unstable control of the outlet temperature of the medium-speed coal mill. Low, in severe cases, it will affect the safe and stable operation of the coal mill. The power grid company requires that the on-grid thermal power generation unit must have the function of frequency regulation and peak regulation, and put forward specific technical indicators and assessment methods. The thermal power unit coordination control system is the highest level controller in the unit control, responsible for coordinating the energy balance control between the steam turbine and the boiler, and ensuring the adjustment quality of the unit participating in the frequency regulation and peak regulation of the power grid. The controlled object of unit coordinated control is a multi-input and multi-output system, which has the characteristics of nonlinearity, slow time-varying parameters, large hysteresis and large inertia. It is especially reflected in the control link of changing operating conditions. In the whole process of peak regulation and frequency regulation, it involves the control process of starting, stopping, coal supply increase and coal supply decrease of the medium-speed coal mill. In order to meet the coordination control The load control of the system requires that the outlet temperature control of the medium-speed coal mill must be stable and reliable to ensure the safety and stability of the medium-speed coal mill during operation, which brings many difficulties to the outlet temperature control of the medium-speed coal mill.

In recent years, many domestic scholars have researched and discussed issues related to the temperature control of the outlet temperature of the medium-speed coal mill of thermal power units, such as "The Effect of Increasing the Outlet Temperature of the Medium-speed Coal Mill on Boiler Operation" published by "China Electric Power", the coal mill When the outlet temperature rises from 75°C to 95°C, the temperature of the hot air at the inlet of the coal mill rises to 261.4°C, there is no CO in the pulverized coal flow at the outlet of the coal mill, and the temperature of the primary air and secondary air at the outlet of the air preheater both increase. The furnace combustion and operating parameters did not change much, the exhaust gas temperature decreased by about 7°C, the boiler efficiency increased by 0.37%, and the standard coal consumption rate for power generation decreased by 1.17 g/(kW·h). "Application Research of a Parameter Adaptive Fuzzy PI Controller in the Supercritical Coal Mill Outlet Temperature Control System" published by "Guangdong Electric Power" aims at the shortcomings of difficult control of the coal mill outlet temperature, and proposes a parameter adaptive fuzzy proportional-integral (PI) control strategy, which uses the real-time trend in the control process combined with the fuzzy control rule library to adjust the proportional factor of the output part of the adaptive fuzzy PI controller online, and dynamically control the cold air when the inlet temperature changes. The opening of the door baffle makes the system output equal to the given temperature, which improves the dynamic characteristics of the coal mill outlet temperature control system.

The above documents mainly elaborate on the benefits of increasing the outlet temperature of the coal mill, parameter setting of the cold air door baffle of the coal mill, etc., and draw conclusions from experiments and parameter setting methods. There is no targeted research on the coordinated actions of the door, the hot primary air regulating door, and the outlet pressure control actuator of the primary fan to ensure that the outlet temperature of the medium-speed coal mill meets the requirements.

Contents of the invention

Aiming at the problems existing in the above-mentioned prior art, the present invention provides a method for optimizing outlet temperature control of medium-speed coal mills of thermal power units. , while meeting the requirements of frequency modulation and peak regulation of the power grid, it also ensures the stability of the outlet temperature of the medium-speed coal mill.

The purpose of the present invention is achieved through the following technical solutions:

The outlet temperature control optimization method of the medium-speed coal mill of thermal power unit is to design the control logic of the cold primary air regulating door, the control logic of the hot primary air regulating door and the The primary air pressure setting value correction amount control logic controls the coordinated action of the cold primary air regulating door, hot primary air regulating door, and primary fan outlet pressure control actuator to ensure that the outlet temperature of the medium-speed coal mill meets the requirements, specifically including the following steps:

Step 1: Add the following PID regulators in the control logic configuration of the DCS of the thermal power unit distributed control system: the PID regulator for the cold primary air adjustment door for the outlet temperature of the medium-speed coal mill, the heat primary air regulator for the outlet temperature of the medium-speed coal mill Wind control door PID regulator;

Step 2: Add the following interlocking control logic in the control logic configuration of the DCS of the thermal power unit distributed control system: the opening interlocking control logic of the hot primary air regulating door of the medium-speed coal mill, and the interlocking control of the correction value of the primary air pressure setting value logic;

Step 3: In the control logic primary air pressure control loop configuration of the decentralized control system DCS of the thermal power unit, add the primary air pressure setting value correction amount control loop interface based on the medium-speed coal mill outlet temperature control optimization, and set the primary air pressure The output of the interlocking control logic of the correction value of the pressure setting value is introduced into the control circuit interface of the correction value of the primary air pressure setting value based on the optimization of the outlet temperature control of the medium-speed coal mill as the correction value of the primary air pressure control;

Step 4: The control system is put into actual operation. According to the real-time operation curve, the relevant parameters of each control loop for the outlet temperature control of the medium-speed coal mill of the thermal power unit are adjusted online, and finally the expected control effect is achieved.

The cold primary air regulating door PID regulator for the outlet temperature of the medium-speed coal mill described in the first step includes: the actual measured value A of the outlet temperature of the medium-speed coal mill, the artificially set value target value of the outlet temperature of the medium-speed coal mill B. Calculate the difference C between A and B, and perform PID calculation on the difference C. The PID calculation can obtain the opening degree command of the cold primary air adjustment door for the outlet temperature of the medium-speed coal mill; The PID regulator of the wind regulating door includes: the actual measured value A of the outlet temperature of the medium-speed coal mill, the artificially set value target value D of the outlet temperature of the medium-speed coal mill, calculate the difference E between A and D, and perform PID on the difference E Operation, PID operation to obtain the opening degree command of the hot primary air regulating door for the outlet temperature of the medium-speed coal mill.

The opening chain control logic of the hot primary air regulating door of the medium-speed coal mill described in the second step includes: when the opening of the cold primary air regulating door of the medium-speed coal mill outlet temperature is less than F, the outlet of the medium-speed coal mill The lower limit chain opening degree of the hot primary air regulating door for temperature is G, the upper limit is 100, the adjustment range of the PID regulator for controlling the hot primary air regulating door is G~100, and the opening degree of the cold primary air regulating door for the outlet temperature of the medium-speed coal mill When it is greater than H, the lower limit chain opening degree of the thermal primary air regulating door of the outlet temperature of the medium-speed coal mill is I, the upper limit is 100, and the adjustment range of the PID regulator for controlling the thermal primary air regulating door is I~100, and the medium-speed coal pulverizer When the inlet primary air pressure is less than J, the hot primary air regulating door of the outlet temperature of the medium-speed coal mill is locked and closed, and the PID regulator for controlling the hot primary air regulating door is closed. The hot primary air regulating door of the outlet temperature of the speed coal mill is locked and closed, and the PID regulator for controlling the hot primary air regulating door is locked and closed.

The interlocking control logic of the primary air pressure setting value correction amount described in the second step includes that when the actual measured value A of the outlet temperature of the medium-speed coal mill is higher than the alarm value, the opening of the hot primary air adjustment door reaches the lower limit at the same time, and When the opening of the cold primary air adjustment door reaches the upper limit value, the correction value A of the set value of the primary air pressure is triggered in a chain to be effective. The function f ₁ (x) is realized. When the actual measured value A of the outlet temperature of the medium-speed coal mill is lower than the alarm value, at the same time, the opening of the hot primary air regulating door reaches the upper limit, and the opening of the cold primary air regulating door reaches the lower limit. , the correction value B of the set value of the primary air pressure is triggered in chain to be effective, and the amplitude value of the correction value of the set value of the primary air pressure is realized by the function f ₂ (x) of the actual measured value A of the outlet temperature of the medium-speed coal mill. When the primary air speed at the outlet of the coal machine is less than L, the chain trigger primary air pressure setting value correction value C is valid, and the amplitude value of the primary air pressure setting value correction value is a function of the actual measured value of the primary air speed at the medium-speed coal mill outlet f ₃ (x) is realized.

The algorithmic logic of the cold primary air regulating door, hot primary air regulating door, and primary air pressure setting value correction is: the actual measured value of the outlet temperature of the medium-speed coal mill, the opening of the cold primary air regulating door, and the opening of the hot primary air pressure. The opening of the regulating door, the primary air pressure at the entrance of the medium-speed coal mill, and the primary air speed at the exit of the medium-speed coal mill can all be directly read from the real-time database of the unit distributed control system DCS; switching conditions: the opening of the cold primary air regulating door is less than F, the opening of the cold primary air adjustment door is greater than H, the primary air pressure at the entrance of the medium-speed coal mill is less than J, the primary air speed at the exit of the medium-speed coal mill is less than K, and the actual measured value A of the medium-speed coal mill outlet temperature is higher than the alarm value, the opening of the hot primary air regulating door reaches the lower limit, the opening of the cold primary air regulating door reaches the upper limit, the actual measured value A of the outlet temperature of the medium-speed coal mill is lower than the alarm value, and the opening of the hot primary air regulating door reaches The upper limit value, the opening of the cold primary air adjustment door reaches the lower limit value, and the primary air speed at the outlet of the medium-speed coal mill is less than L, which is obtained by logical judgment; f ₁ (x) is a nonlinear function generator, and its input is medium The actual measured value A of the outlet temperature of the high-speed coal mill is output as the correction value A of the primary air pressure setting value. The following conditions must be met for the output to be valid: the actual measured value A of the outlet temperature of the medium-speed coal mill is higher than the alarm value. The opening of the regulating door reaches the lower limit, and the opening of the cold primary air regulating door reaches the upper limit; f ₂ (x) is a nonlinear function generator, its input is the actual measured value of the outlet temperature of the medium-speed coal mill, and the output is Correction value B of the primary air pressure setting value, the output must meet the following conditions: the actual measured value A of the outlet temperature of the medium-speed coal mill is lower than the alarm value, and at the same time, the opening of the hot primary air adjustment door reaches the upper limit value, and the cold primary air The opening of the regulating door reaches the lower limit; f ₃ (x) is a nonlinear function generator, whose input is the actual measured value of the primary air velocity at the outlet of the medium-speed coal mill, and the output is the correction value C of the primary air pressure setting value, and the output To be effective, the following conditions must be met: the primary air speed at the outlet of the medium-speed coal mill is less than L; the parameters of f ₁ (x), f ₂ (x), and f ₃ (x) can be set online according to the real-time curve. The organic unit distributed control system DCS coordination control system ensures that the unit can automatically control the outlet temperature of the medium-speed coal mill within a reasonable range during the operation of the unit.

Advantage of the present invention and beneficial effect are:

(1) By designing the control logic of the cold primary air regulating door, the hot primary air regulating door and the primary air pressure setting value correction control logic of the medium-speed coal mill, the control of the cold primary air regulating door and the hot primary air regulating The door and the outlet pressure control actuator of the primary fan coordinate actions to ensure that the outlet temperature of the medium-speed coal mill meets the requirements, so as to realize the full potential of the equipment and ensure the stability of the outlet temperature of the unit's medium-speed coal mill while meeting the operating requirements.

(2) It can effectively reduce the labor intensity of the operating personnel, and the control effect does not depend on the technical level of the operating personnel.

(3) The real-time performance is good, the on-site debugging process is simple, and it is convenient for engineering realization.

Description of drawings

The present invention will be described in further detail below in conjunction with the accompanying drawings and specific embodiments.

Fig. 1 is the control logic diagram of the cold primary air regulating door and the hot primary air regulating door of the algorithm of the present invention;

Fig. 2 is the logic diagram of the primary wind pressure setting value correction amount of the algorithm of the present invention;

Fig. 3 is a workflow block diagram of the present invention.

detailed description

The invention is a method for optimizing the outlet temperature control of a medium-speed coal mill of a thermal power unit. The regulating door control logic and the primary air pressure setting value correction control logic control the cold primary air regulating door, the hot primary air regulating door, and the primary fan outlet pressure control actuator to coordinate actions to ensure that the outlet temperature of the medium-speed coal mill meets the requirements, such as As shown in Figure 3, it specifically includes the following steps:

Step 1: Add the following PID regulators in the control logic configuration of the DCS of the thermal power unit distributed control system: the PID regulator for the cold primary air adjustment door for the outlet temperature of the medium-speed coal mill, the heat primary air regulator for the outlet temperature of the medium-speed coal mill Wind adjustment door PID regulator.

Among them: DCS is the English abbreviation of Distributed Control System (Distributed Control System).

PID regulator is the English abbreviation of proportional integral differential regulator (Proportion Integration Differentiation).

Step 2: Add the following interlocking control logic in the control logic configuration of the DCS of the thermal power unit distributed control system: the opening interlocking control logic of the hot primary air regulating door of the medium-speed coal mill, and the interlocking control of the correction value of the primary air pressure setting value logic;

Step 3: In the control logic primary air pressure control loop configuration of the decentralized control system DCS of the thermal power unit, add the primary air pressure setting value correction amount control loop interface based on the medium-speed coal mill outlet temperature control optimization, and set the primary air pressure The output of the interlocking control logic of the correction value of the pressure setting value is introduced into the control circuit interface of the correction value of the primary air pressure setting value based on the optimization of the outlet temperature control of the medium-speed coal mill as the correction value of the primary air pressure control;

Step 4: The control system is put into actual operation. According to the real-time operation curve, the relevant parameters of each control loop for the outlet temperature control of the medium-speed coal mill of the thermal power unit are adjusted online, and finally the expected control effect is achieved.

The cold primary air regulating door PID regulator for the outlet temperature of the medium-speed coal mill described in the first step includes: the actual measured value A of the outlet temperature of the medium-speed coal mill, and the artificially set value target of the outlet temperature of the medium-speed coal mill value B, calculate the difference C between A and B, and perform PID calculation on the difference C, and the PID calculation can obtain the opening degree command of the cold primary air adjustment door for the outlet temperature of the medium-speed coal mill; The PID regulator of the primary air regulating door includes: the actual measured value A of the outlet temperature of the medium-speed coal mill, the artificially set value target value D of the outlet temperature of the medium-speed coal mill, the calculation of the difference E between A and D, and the difference E PID operation, PID operation to obtain the opening degree command of the hot primary air regulating door for the outlet temperature of the medium-speed coal mill.

The opening chain control logic of the hot primary air regulating door of the medium-speed coal mill described in the second step includes: when the opening of the cold primary air regulating door of the medium-speed coal mill outlet temperature is less than F, the outlet of the medium-speed coal mill The lower limit chain opening degree of the hot primary air regulating door for temperature is G, the upper limit is 100, the adjustment range of the PID regulator for controlling the hot primary air regulating door is G~100, and the opening degree of the cold primary air regulating door for the outlet temperature of the medium-speed coal mill When it is greater than H, the lower limit chain opening degree of the thermal primary air regulating door of the outlet temperature of the medium-speed coal mill is I, the upper limit is 100, and the adjustment range of the PID regulator for controlling the thermal primary air regulating door is I~100, and the medium-speed coal pulverizer When the inlet primary air pressure is less than J, the hot primary air regulating door of the outlet temperature of the medium-speed coal mill is locked and closed, and the PID regulator for controlling the hot primary air regulating door is closed. The hot primary air regulating door of the outlet temperature of the speed coal mill is locked and closed, and the PID regulator for controlling the hot primary air regulating door is locked and closed.

The interlocking control logic of the primary air pressure setting value correction amount described in the second step includes that when the actual measured value A of the outlet temperature of the medium-speed coal mill is higher than the alarm value, the opening of the hot primary air adjustment door reaches the lower limit at the same time, and When the opening of the cold primary air adjustment door reaches the upper limit value, the correction value A of the set value of the primary air pressure is triggered in a chain to be effective. The function f ₁ (x) is realized. When the actual measured value A of the outlet temperature of the medium-speed coal mill is lower than the alarm value, at the same time, the opening of the hot primary air regulating door reaches the upper limit, and the opening of the cold primary air regulating door reaches the lower limit. , the correction value B of the set value of the primary air pressure is triggered in chain to be effective, and the amplitude value of the correction value of the set value of the primary air pressure is realized by the function f ₂ (x) of the actual measured value A of the outlet temperature of the medium-speed coal mill. When the primary air speed at the outlet of the coal machine is less than L, the chain trigger primary air pressure setting value correction value C is valid, and the amplitude value of the primary air pressure setting value correction value is a function of the actual measured value of the primary air speed at the medium-speed coal mill outlet f ₃ (x) is realized.

The algorithmic logic of the cold primary air regulating door, hot primary air regulating door, and primary air pressure setting value correction is: the actual measured value of the outlet temperature of the medium-speed coal mill, the opening of the cold primary air regulating door, and the opening of the hot primary air pressure. The opening of the regulating door, the primary air pressure at the entrance of the medium-speed coal mill, and the primary air speed at the exit of the medium-speed coal mill can all be directly read from the real-time database of the unit distributed control system DCS; switching conditions: the opening of the cold primary air regulating door is less than F, the opening of the cold primary air adjustment door is greater than H, the primary air pressure at the entrance of the medium-speed coal mill is less than J, the primary air speed at the exit of the medium-speed coal mill is less than K, and the actual measured value A of the medium-speed coal mill outlet temperature is higher than the alarm value, the opening of the hot primary air regulating door reaches the lower limit, the opening of the cold primary air regulating door reaches the upper limit, the actual measured value A of the outlet temperature of the medium-speed coal mill is lower than the alarm value, and the opening of the hot primary air regulating door reaches The upper limit value, the opening of the cold primary air adjustment door reaches the lower limit value, and the primary air speed at the outlet of the medium-speed coal mill is less than L, which is obtained by logical judgment; f ₁ (x) is a nonlinear function generator, and its input is medium The actual measured value A of the outlet temperature of the high-speed coal mill is output as the correction value A of the primary air pressure setting value. The following conditions must be met for the output to be valid: the actual measured value A of the outlet temperature of the medium-speed coal mill is higher than the alarm value. The opening of the regulating door reaches the lower limit, and the opening of the cold primary air regulating door reaches the upper limit; f ₂ (x) is a nonlinear function generator, its input is the actual measured value of the outlet temperature of the medium-speed coal mill, and the output is Correction value B of the primary air pressure setting value, the output must meet the following conditions: the actual measured value A of the outlet temperature of the medium-speed coal mill is lower than the alarm value, and at the same time, the opening of the hot primary air adjustment door reaches the upper limit value, and the cold primary air The opening of the regulating door reaches the lower limit; f ₃ (x) is a nonlinear function generator, whose input is the actual measured value of the primary air velocity at the outlet of the medium-speed coal mill, and the output is the correction value C of the primary air pressure setting value, and the output To be effective, the following conditions must be met: the primary air speed at the outlet of the medium-speed coal mill is less than L; the parameters of f ₁ (x), f ₂ (x), and f ₃ (x) can be set online according to the real-time curve. The organic unit distributed control system DCS coordination control system ensures that the unit can automatically control the outlet temperature of the medium-speed coal mill within a reasonable range during the operation of the unit.

The core idea of the present invention is to realize the control of the cold primary air regulating door, the hot primary air regulating The coordinated actions of the primary air regulating door and the outlet pressure control actuator of the primary fan ensure that the outlet temperature of the medium-speed coal mill meets the requirements, so as to realize the full potential of the equipment and ensure the stability of the outlet temperature of the medium-speed coal mill of the unit while meeting the operation requirements sex.

The algorithm logic diagram of the intermediate cold primary air regulating door and the hot primary air regulating door of the present invention, that is, the control logic of the cold primary air regulating door and the hot primary air regulating door of the thermal power unit medium-speed coal mill outlet temperature control optimization method is shown in Figure 1 . In Figure 1, the actual measured value of the outlet temperature of the medium-speed coal mill, the opening of the cold primary air regulating door, the opening of the hot primary air regulating door, and the primary air pressure of the medium-speed coal mill inlet can all be directly obtained from the DCS of the distributed control system of the unit in real time. Read from the database; switching conditions: the opening of the cold primary air adjustment door is less than F, the opening of the cold primary air adjustment door is greater than H, the primary air pressure at the entrance of the medium-speed coal mill is less than J, and the primary air speed at the exit of the medium-speed coal mill is less than K, obtained by logical judgment.

The logic diagram of the primary air pressure setting value correction algorithm logic diagram in the present invention, that is, the primary air pressure setting value correction amount control logic of the thermal power unit medium-speed coal mill outlet temperature control optimization method is shown in FIG. 2 . In Figure 2, the actual measured value of the outlet temperature of the medium-speed coal mill, the opening of the cold primary air regulating door, the opening of the hot primary air regulating door, and the primary air velocity of the medium-speed coal mill outlet can all be directly obtained from the distributed control system DCS of the unit in real time. Read from the database; switching conditions: the actual measured value A of the outlet temperature of the medium-speed coal mill is higher than the alarm value, the opening of the hot primary air adjustment door reaches the lower limit, the opening of the cold primary air adjustment door reaches the upper limit, and the medium-speed The actual measured value A of the outlet temperature of the coal mill is lower than the alarm value, the opening of the hot primary air adjustment door reaches the upper limit, the opening of the cold primary air adjustment door reaches the lower limit, and the primary air speed of the medium-speed coal mill outlet is less than L, It can be concluded from logical judgment; f ₁ (x) is a nonlinear function generator, its input is the actual measured value A of the outlet temperature of the medium-speed coal mill, and its output is the correction value A of the primary air pressure setting value. The effective output must meet the following Condition: The actual measured value A of the outlet temperature of the medium-speed coal mill is higher than the alarm value, and at the same time, the opening of the hot primary air regulating door reaches the lower limit, and the opening of the cold primary air regulating door reaches the upper limit; f ₂ (x) is Non-linear function generator, whose input is the actual measured value of the outlet temperature of the medium-speed coal mill, and the output is the correction value B of the primary air pressure setting value, and the output must meet the following conditions for valid output: the actual measured value of the outlet temperature of the medium-speed coal mill A is lower than the alarm value, and at the same time, the opening of the hot primary air regulating door reaches the upper limit, and the opening of the cold primary air regulating door reaches the lower limit; f ₃ (x) is a nonlinear function generator, and its input is medium-speed pulverized coal The actual measurement value of the primary air velocity at the outlet of the pulverizer, the output is the correction value C of the primary air pressure setting value, and the following conditions must be met for the output to be valid: the primary air velocity at the outlet of the medium-speed coal pulverizer is less than L; f ₁ (x), f ₂ (x ), f ₃ (x) parameters can be set online according to the real-time curve. The principle of setting is to ensure that the outlet temperature of the medium-speed coal mill is automatically controlled at within a reasonable range.

Taking the outlet temperature control of a medium-speed coal mill of a 300MW thermal power unit as an example, the algorithm parameter setting results are introduced, as shown in Table 1.

Unit overview: The coal mill of this unit is a medium-speed coal mill. The pulverizing system adopts positive pressure direct blowing type. It is equipped with 5 coal mills. Each coal mill is equipped with a hot primary air adjustment door and a cold primary air The air regulating door is equipped with two primary fans with 50% capacity to provide primary hot and cold air to transport pulverized coal.

As shown in Table 1, Table 1 is the control parameter setting of the cold primary air regulating door, hot primary air regulating door and primary air pressure setting value correction amount of the medium-speed coal mill.

The x corresponding to f ₁ (x) in Table 1 is the actual measured value of the outlet temperature of the medium-speed coal mill (°C); the x corresponding to f ₂ (x) is the actual measured value of the outlet temperature of the medium-speed coal mill (°C) ; x corresponding to f ₃ (x) is the actual measured value of the primary air velocity at the outlet of the medium-speed coal mill (m/s); the actual measured value of the outlet temperature of the medium-speed coal mill of the unit, and the opening of the cold primary air adjustment , the opening of the hot primary air adjustment door, and the primary air speed at the outlet of the medium-speed coal mill can be directly read from the DCS real-time database of the distributed control system of the unit; Put into actual operation, according to the operating curve of the unit, repeatedly adjust the corresponding parameters of f ₁ (x), f ₂ (x), and f ₃ (x) online to ensure that the unit can automatically control the main steam pressure at a reasonable level while the load response is fast and stable. Within the scope; the on-site debugging process is simple and convenient for engineering realization.

Claims (5)

1. fired power generating unit medium-speed pulverizer outlet temperature control optimization method, is characterized in that, in fired power generating unit scattered control system The cold First air that medium-speed pulverizer is set up in the control logic configuration of DCS adjusts gate control logic, heat primary air regulation gate control Logical sum primary air pressure set point correct amount control logic, controls cold First air and adjusts door, heat primary air regulation door and Secondary fan outlet Stress control actuator, specifically includes following steps：

The first step：Increase following PID regulator in the control logic configuration of fired power generating unit distributed monitoring control system：Medium-speed pulverizer The cold First air of coal machine outlet temperature adjusts door PID regulator, and the heat primary air of medium-speed pulverizer outlet temperature adjusts door PID and adjusts Section device；

Second step：Increase following chain control logic in the control logic configuration of fired power generating unit distributed monitoring control system：Middling speed Coal pulverizer heat primary air adjusts the aperture chain control logic of door, primary air pressure set point correct amount chain control logic；

3rd step：Increase base in the control logic primary air pressure control loop configuration of fired power generating unit distributed monitoring control system The primary air pressure set point correct amount control loop interface of optimization is controlled in medium-speed pulverizer outlet temperature, and by primary air pressure The output of power set point correct amount chain control logic is incorporated into the First air that optimization is controlled based on medium-speed pulverizer outlet temperature As the correction of primary air pressure control in pressure set points correction control loop interface；

4th step：Control system puts into actual motion, and according to real time execution curve, on-line tuning fired power generating unit medium-speed pulverizer goes out Mouthful temperature control each control loop relevant parameter, is finally reached expected control effect.

2. fired power generating unit medium-speed pulverizer outlet temperature according to claim 1 controls optimization method, it is characterised in that：Institute In the first step stated, the cold First air of medium-speed pulverizer outlet temperature adjusts door PID regulator to be included：Medium-speed pulverizer outlet temperature Degree actual measured value A, medium-speed pulverizer outlet temperature is manually set value desired value B, calculates difference C of A and B, and difference C is carried out PID arithmetic, PID arithmetic show that the cold First air of medium-speed pulverizer outlet temperature adjusts door opening degree instruction；Medium-speed pulverizer is exported The heat primary air of temperature adjusts door PID regulator to be included：Medium-speed pulverizer outlet temperature actual measured value A, medium-speed pulverizer goes out Mouth temperature is manually set value desired value D, calculates difference E of A and D, and to difference E PID arithmetic is carried out, and PID arithmetic draws medium-speed pulverizer The heat primary air of coal machine outlet temperature adjusts door opening degree instruction.

3. fired power generating unit medium-speed pulverizer outlet temperature according to claim 1 controls optimization method, it is characterised in that：Institute In the second step stated, medium-speed pulverizer heat primary air adjusts the aperture chain control logic of door to be included：When medium-speed pulverizer outlet When the cold First air of temperature adjusts door aperture and is less than F, the heat primary air of medium-speed pulverizer outlet temperature adjusts that door lower limit is chain to be opened Spend for G, the upper limit is 100, it is G ~ 100 to control heat primary air and adjust the range of accommodation of door PID regulator, when medium-speed pulverizer outlet When the cold First air of temperature adjusts door aperture and is more than H, the heat primary air of medium-speed pulverizer outlet temperature adjusts that door lower limit is chain to be opened Spend for I, the upper limit is 100, it is I ~ 100 to control heat primary air and adjust the range of accommodation of door PID regulator, when medium-speed pulverizer entrance When primary air pressure is less than J, the heat primary air of medium-speed pulverizer outlet temperature adjusts door locking and closes, and control heat primary air is adjusted The locking of door PID regulator is closed, when medium-speed pulverizer outlet First air speed is less than K, the heat of medium-speed pulverizer outlet temperature First air adjusts door locking and closes, and control heat primary air adjusts the locking of door PID regulator and closes.

4. fired power generating unit medium-speed pulverizer outlet temperature according to claim 1 controls optimization method, it is characterised in that：Institute In the second step stated, primary air pressure set point correct amount chain control logic includes being surveyed when medium-speed pulverizer outlet temperature is actual When value A is higher than alarming value, while heat primary air adjusts door aperture reaches lower limit, and cold First air adjusts door aperture and reaches Higher limit, chain triggering primary air pressure set point correct amount A effectively, the range value of this primary air pressure set point correct amount by The function f of medium-speed pulverizer outlet temperature actual measured value A₁X () is realized, when medium-speed pulverizer outlet temperature actual measured value A During less than alarming value, while heat primary air adjusts door aperture reaches higher limit, and cold First air adjusts door aperture and reaches lower limit Value, effectively, the range value of this primary air pressure set point correct amount is by middling speed for chain triggering primary air pressure set point correct amount B The function f of pulverizer outlet temperature actual measured value A₂X () is realized, when medium-speed pulverizer outlet First air speed is less than L, even Effectively, the range value of this primary air pressure set point correct amount is by middling speed coal-grinding for lock triggering primary air pressure set point correct amount C Machine exports the function f of First air speed actual measured value₃X () is realized.

5. fired power generating unit medium-speed pulverizer outlet temperature according to claim 1 controls optimization method, it is characterised in that：Institute The cold First air stated adjusts the algorithm logic of door, heat primary air regulation door and primary air pressure set point correct amount：Medium-speed pulverizer Coal machine outlet temperature actual measured value, cold First air adjusts door aperture, and heat primary air adjusts door aperture, medium-speed pulverizer entrance one Secondary wind pressure, medium-speed pulverizer outlet First air speed can directly reading in slave group distributed monitoring control system real-time data base Take；Switching condition：Cold First air adjusts door aperture and is less than F, and cold First air adjusts door aperture and is more than H, medium-speed pulverizer entrance one Secondary wind pressure is less than J, and medium-speed pulverizer outlet First air speed is less than K, and medium-speed pulverizer outlet temperature actual measured value A is higher than Alarming value, heat primary air adjusts door aperture and reaches lower limit, and cold First air adjusts door aperture and reaches higher limit, and medium-speed pulverizer goes out Mouth temperature actual measured value A is less than alarming value, and heat primary air adjusts door aperture and reaches higher limit, and cold First air adjusts door aperture and arrives Up to lower limit, medium-speed pulverizer outlet First air speed is less than L, is drawn by logical judgment；f₁X () is nonlinear function generation Device, its input is medium-speed pulverizer outlet temperature actual measured value A, is output as primary air pressure set point correct amount A, and output has Effect need to meet following condition：Medium-speed pulverizer outlet temperature actual measured value A is higher than alarming value, while heat primary air adjusts door opening Degree reaches lower limit, and cold First air adjusts door aperture and reaches higher limit；f₂X () is non-linear function generator, its input For medium-speed pulverizer outlet temperature actual measured value, primary air pressure set point correct amount B is output as, under output effectively need to meet Row condition：Medium-speed pulverizer outlet temperature actual measured value A is less than alarming value, while heat primary air adjusts door aperture reaches the upper limit Value, and cold First air adjusts door aperture arrival lower limit；f₃X () is non-linear function generator, its input is middling speed coal-grinding Machine exports First air speed actual measured value, is output as primary air pressure set point correct amount C, and output need to effectively meet following bar Part：Medium-speed pulverizer outlet First air speed is less than L；f₁(x)、f₂(x)、f₃X the parameter of () can be whole online according to real-time curve Fixed, the principle adjusted is by existing unit distributed monitoring control system coordinated control system, it is ensured that unit in running, Automatically medium-speed pulverizer outlet temperature is controlled in the reasonable scope.