CN-117128609-B - Self-adaptive nonlinear control method for temperature and humidity of air conditioner

CN117128609BCN 117128609 BCN117128609 BCN 117128609BCN-117128609-B

Abstract

The invention relates to an air conditioner temperature and humidity self-adaptive nonlinear control method which comprises the following steps of 1, taking humidity source intensity, heat load, outdoor humidity ratio and outdoor temperature as unknown quantities to establish a nonlinear dynamic model of an air processing unit temperature and humidity control system, then carrying out system transformation, 2, establishing a serial-parallel estimation model to obtain a humidity source intensity estimated value and a heat load estimated value, 3, establishing a humidity control signal to control indoor humidity to reach an expected value, designing a first humidity source intensity self-adaptive law to process the humidity source intensity estimated value, 4, establishing a virtual control signal and a heat load self-adaptive law to process the heat load, designing a first poplar inequality and a second humidity source intensity self-adaptive law to process the humidity source intensity estimated value, 5, designing a second poplar inequality to process unknown change humidity ratio and unknown change temperature, 6, establishing a temperature control signal to control the indoor temperature to reach the expected value, and achieving high control accuracy.

Inventors

LIU CUNGEN
LIU JIHUA
LIU XIAOPING
WANG HUANQING
SUN YULONG

Assignees

山东建筑大学

Dates

Publication Date: 20260505
Application Date: 20230816

Claims (1)

1. The adaptive nonlinear control method for the temperature and the humidity of the air conditioner is characterized by comprising the following steps of: The method comprises the steps of 1, establishing a nonlinear dynamic model of a temperature and humidity control system of an air handling unit by taking humidity source intensity, heat load, outdoor humidity ratio and outdoor temperature as unknown quantities, wherein the outdoor humidity ratio comprises a known humidity ratio and an unknown variation humidity ratio, and the outdoor temperature comprises a known temperature and an unknown variation temperature; Step 2, constructing a serial-parallel estimation model, and estimating unknown humidity source intensity and thermal load by adopting the serial-parallel estimation model to obtain a humidity source intensity estimated value and a thermal load estimated value; Step 3, establishing a humidity control signal to control indoor humidity to reach an expected value, and designing a first humidity source intensity self-adaptive law to process the humidity source intensity estimated value in the step 2; step 4, constructing a virtual control signal and a heat load self-adaptive law to process the heat load in the step 1, and designing a first poplar inequality and a second humidity source intensity self-adaptive law to process the humidity source intensity estimated value in the step 2; step 5, designing a second poplar inequality to process the unknown change humidity ratio and the unknown change temperature in the step 1; step6, establishing a temperature control signal to control the indoor temperature to reach an expected value; in step 1, a nonlinear dynamic model of a temperature and humidity control system of an air handling unit is as follows: (1); Wherein, the Is the humidity ratio of the room, In order to provide the air supply humidity ratio, Is the temperature of the room in which the temperature is to be controlled, For the air supply temperature, Is the temperature gradient of the heat exchanger, Is the intensity of the source of unknown humidity, For an unknown thermal load, Is the volume of the indoor space, For the volume of the cooling device, Is the air flow rate of the blower, In order to control the flow of cooling water to the valve, For the outdoor temperature to be the same, For a given temperature to be known, In order for the temperature of the change to be unknown, In order to be an outdoor humidity ratio, As a result of the known humidity ratio, In order for the humidity ratio to vary unknowingly, Is the specific heat of air, and the air is heated, Is the specific heat of water, and the water is the water, Is the enthalpy of the saturated water, and the water is saturated, In order to provide an enthalpy of vaporization, In order to achieve an air density of the air, Is the water density of the water, the water is in a water-tight state, The fresh air ratio in the air supply is used, Is the air return duty ratio in the air supply and ; In step 1, the system transforms into: (2); Wherein, the In the event of a humidity control signal, In the form of a temperature control signal, , , , , ; Parameters (parameters) , , The expression is as follows: , , , , , , ; in step 2, the serial-parallel estimation model is: (3); Wherein, the In order to observe the error in the image, And Is a normal number of times, and the number of times is equal to the normal number, And Respectively is And Is used for the estimation of the (c), Is a humidity control signal; in step3, the humidity control signal is: (4); Wherein, the Is a positive design parameter that is used to determine the design, , Is the target humidity; In step 3, the first humidity source intensity adaptive law is: (5); Wherein, the And Is a positive constant; in step 4, the virtual control signal is , (6); Wherein, the Is a positive design parameter that is used to determine the design, , Is the target temperature; The thermal load adaptation law is: (7); Wherein, the And Is a positive constant; In step 4, the first poplar inequality is: (8); Wherein, the Is a positive constant which is a function of the current, , , Is that Is a function of the estimated value of (2); the second humidity source intensity adaptation law is: (9); Wherein, the And Is a positive constant; in step 5, the second poplar inequality is: (10); Wherein, the And Is a positive design parameter that is used to determine the design, , , And Respectively are And Is the upper limit of (2) and is a normal number; In step 6, the temperature control signal is : (11); Wherein, the Is a positive design parameter that is used to determine the design, 。

Description

Self-adaptive nonlinear control method for temperature and humidity of air conditioner Technical Field The invention belongs to the technical field of air conditioner temperature and humidity control, and particularly relates to an air conditioner temperature and humidity self-adaptive nonlinear control method. Background A typical heating ventilation air conditioning system consists of a plurality of loops, each loop has a plurality of mutual variables, each link has high nonlinearity, and a plurality of uncertain factors such as time-varying characteristics, coupling, time lags, disturbance and the like lead the whole heating ventilation air conditioning system to form a typical complex nonlinear multivariable system. The Chinese patent publication CN116336617A discloses a nonlinear control method of an air handling unit, which is designed directly for a nonlinear mathematical model of the air handling unit, and the influence degree of disturbance on the output of the system is attenuated to a given degree by a nearly disturbance decoupling technology. The nonlinear mathematical model of the air handling unit disclosed in the above patent publication has the defect that the humidity source intensity, the heat load, the outdoor humidity ratio and the outdoor temperature are taken as disturbance, the disturbance is divided into a known constant and a bounded function to perform almost disturbance decoupling treatment, and the treatment mode has limitations. Because the problem of system balance shift is unavoidable when treating the humidity source intensity, heat load, outdoor humidity ratio and outdoor temperature as unknown. Because the processing of almost disturbance decoupling needs to ensure that the fluctuation of the bounded function is smaller, the system balance point cannot deviate, namely, if the fluctuation of the bounded function is larger, the system balance point deviates, and the problem is not fundamentally solved. Disclosure of Invention The invention aims to solve the technical problem of overcoming the defects of the prior art and providing a self-adaptive nonlinear control method for temperature and humidity of an air conditioner. The technical scheme of the invention is as follows: An adaptive nonlinear control method for temperature and humidity of an air conditioner comprises the following steps: The method comprises the steps of 1, establishing a nonlinear dynamic model of a temperature and humidity control system of an air handling unit by taking humidity source intensity, heat load, outdoor humidity ratio and outdoor temperature as unknown quantities, wherein the outdoor humidity ratio comprises a known humidity ratio and an unknown variation humidity ratio, and the outdoor temperature comprises a known temperature and an unknown variation temperature; Step 2, constructing a serial-parallel estimation model, and estimating unknown humidity source intensity and thermal load by adopting the serial-parallel estimation model to obtain a humidity source intensity estimated value and a thermal load estimated value; Step 3, establishing a humidity control signal to control indoor humidity to reach an expected value, and designing a first humidity source intensity self-adaptive law to process the humidity source intensity estimated value in the step 2; step 4, constructing a virtual control signal and a heat load self-adaptive law to process the heat load in the step 1, and designing a first poplar inequality and a second humidity source intensity self-adaptive law to process the humidity source intensity estimated value in the step 2; step 5, designing a second poplar inequality to process the unknown change humidity ratio and the unknown change temperature in the step 1; And 6, establishing a temperature control signal to control the indoor temperature to reach a desired value. Further, in step 1, the nonlinear dynamic model of the temperature and humidity control system of the air handling unit is: (1) Wherein, the Is the humidity ratio of the room,In order to provide the air supply humidity ratio,Is the temperature of the room in which the temperature is to be controlled,For the air supply temperature,Is the temperature gradient of the heat exchanger,Is the intensity of the source of unknown humidity,For an unknown thermal load,Is the volume of the indoor space,For the volume of the cooling device,Is the air flow rate of the blower,In order to control the flow of cooling water to the valve,For the outdoor temperature to be the same,For a given temperature to be known,In order for the temperature of the change to be unknown,In order to be an outdoor humidity ratio,As a result of the known humidity ratio,In order for the humidity ratio to vary unknowingly,Is the specific heat of air, and the air is heated,Is the specific heat of water, and the water is the water,Is the enthalpy of the saturated water, and the water is saturated,In order to provide an enthalpy of vaporization,In order