The method of automatic control of the temperature in the greenhouse
(57) Abstract:Usage: the invention relates to agricultural machinery, and in particular to methods of automatic control of the temperature in the greenhouse. The invention: the invention increases the accuracy of the optimization of temperature and eliminates the need to work at temperatures below permissible. For this additionally determine the age of a plant, the duration of the photoperiod, humidity in the greenhouse, as well as the relative time of the day or night. Specify in accordance with these measurements with optimal productivity, temperature, and optimal consumption temperature compared to the minimum allowable. If the optimum temperature is more valid, then set the optimum temperature, and if the optimum temperature is below limit, then set the allowable temperature. But if the temperature reaches a time limit to the duration of standing, set temperature, optimal productivity. 1 Il. table 1. The invention relates to agricultural machinery, and in particular to methods of automatic control of the temperature in the greenhouse, more specifically to eniah closed and protected ground. Primarily the invention can be used in plastic film greenhouses, but it can be used when optimizing the temperature in a hangar and block greenhouses.There is a method of automatic control of temperature in a greenhouse in which to improve efficiency during the whole growing period of plants is divided into equal intervals, the duration of which is at least an order of magnitude smaller than the time constant of the high-speed perturbations. For this period of time is calculated optimal from the condition of equality to zero of the derivative of the economic criterion temperature. In accordance with this change temperature setpoint the setpoint temperature, ensure the maintenance of constant temperature during the selected period of time.However, the method has great energy and is not very reliable.There is also known a method of automatic control of the temperature in the greenhouse. In the proposed method, taken as a prototype, rather than estimating the maximum profit uses an estimate of the minimum energy consumption. Instead of the model parameters productivity computing device enter parameters which determine the extremum temperature, at which the extremum is provided, from the condition of equality to zero of the derivative of the specific energy consumption. The setpoint knob to change in accordance with a certain way temperature. The transition from day job temperature at night is performed by changing the coefficients in the model.The optimum temperature is preceded by the evaluation of the discriminant. If it is negative, the optimal temperature is determined from the conditions of maximum productivity. In addition, examine the conditions under which the temperature naturally installed in a greenhouse without heating, must be less than optimal temperature. If this condition is not met, then the system switches to summer mode, when instead of heating the ventilation works.However, the method has several disadvantages. First, it does not take into account the age of the plants, the duration of the photoperiod, humidity in the greenhouse. This reduces the accuracy of the determination of the optimal temperature. Secondly, in some cases, determined by the proposed method, the temperature is below the allowable (topt< tSS), and as a result this leads either to the death of plants or to the deterioration of their consumer the Xia long enough. In other words, the restriction must be not only allowable temperature, but also on its duration of standing.Thirdly, recently obtained a more accurate mathematical model of productivity on the basis of which to obtain accurate expressions for determination of optimum temperature.For photosynthesis the resulting model
+A16E +A17Ec+ A23tinT2+A24tinop+
+ A67withwhere E is the illuminance, CLC;
tinthe temperature in the room,
withthe relative time of day.A similar pattern is obtained for the intensity of dark respiration D. Only in this model instead of the current light appears average illuminance of the previous day, instead of the average temperature of the previous night, the average temperature of the day, and instead of the relative time of day relative time of night.The relative time of the day
c= and the relative time of the night
c= current time;
washthe time of sunrise;
n is the number of crossings 24.00 (0 or 1).The numerical values of the coefficients in the model for cucumber variety "Moscow" in the table.The objective of the invention is that it is necessary to increase the accuracy of the optimization of the temperature regime and eliminate work at temperatures less valid.For this purpose, the method of automatic control of the temperature in the greenhouse, including split period of growing plants at regular intervals, measuring in each of these periods of light flux density of solar radiationi optimal productivity and natural temperature, the comparison of these temperatures and in excess of the first over the second turning on the heating system and maintain it at an optimum temperature on productivity, otherwise the inclusion of the ventilation system, the adjustment of the mathematical model of productivity (photosynthesis or dark respiration) and its coefficients for the transitions "day-night" and "night-day", the definition of the magnitude and sign of the discriminant, which characterizes the existence of a minimum energy consumption and, in case of positivity, determination of the optimal intensity, temperature, and change in accordance with the temperature setpoint knob, additionally determine the age of a plant, the duration of the photoperiod, the humidity in the greenhouse, as well as the relative length of day and night, specify in accordance with these measurements as optimal for productivity and energy intensity temperature, and the optimum temperature is compared with the minimum allowable, and if the optimum temperature is more valid, then set the optimum temperature, and if the optimum temperature is below limit, then set the allowable temperature at the duration of elevation which is istwo for automatic control of temperature and humid regime in the industrial houses which takes into account the age of the birds. However, productivity is influenced not only by age in days, but the time of day, which in existing systems is not taken into account.In the invention these drawbacks are eliminated, firstly, by the fact that the above-mentioned factors (age of the plants, the duration of the photoperiod, humidity in the greenhouse) are included in the mathematical model and calculating the optimal temperature; secondly, the fact that in the case when the optimal temperature is below limit, the system supports the allowable temperature, and thirdly, the fact that the allowable temperature is maintained for a timeSSand then rises to optimal productivity.Thus, the inventive method differs in that it uses a more accurate mathematical models of photosynthesis F. and dark respiration D, and, consequently, a more accurate model of the temperature, optimal productivity
In connection with the specification of the mathematical model of optimal consumption temperature
tOPTA= + where
< / BR>tnambient temperature,aboutC;
Q solar radiation flux, W/m2The device comprises a relay 1 and compare 2 elements, the amplifier 3, the actuator 4, the regulator 5 and the sensor 6 air temperature in the greenhouse, as well as a device 7 for calculation of the optimal consumption temperature.The device for calculating the optimal consumption temperature includes unit 8 calculates the optimal productivity of temperature, unit 9 calculating ambient temperature, the unit 10 definition of the discriminant, the Comparators 11 and 12, the adder 13, block 14 calculation of the coefficient of heat loss, the switch 15 modes, integrators light 16 and the daily temperature 17, the generator 18 clock pulses, the counter 19 pulses equalization tank light 20 and a day temperature of 21, the device 22 and memory unit 23 of the input data. The device is also equipped with sensors humidity outdoor air 24, solar radiation 25, the light 26, the relay 27 of the light sensors 28 wind speed and ambient temperature 29. In addition, the system includes sensors age (timer) 30 and humidity inside the space 31. The structure of the device for calculating an optimum temperature introduce additional blocks 32 determine litelle standing permissible temperature permissible duration, and the unit 35 for calculating the relative time of the day or night.The method is as follows.The vegetation period of plants is divided into equal, pre-computed on duration, intervals. The assumption is made that the length must be an order of magnitude smaller than the time constant of the high-speed perturbations. Then, for each time interval is determined optimum temperature, which in this period should be maintained. After determining the length of time the generator 18 clock pulses (GTI) set in this period.The generator produces pulses at specified intervals, during which the processing of information received from sensors 6, 24, 25, 26, 28, 29, 30 and 31. The signals from the sensor 26 of the light sensor of age (timer) 30, sensor humidity indoors 31 are received in block 8 of the calculation of the optimal productivity of temperature. This receives the signal from the block define the duration of the photoperiod 32 (which is in turn determined by the timer 30 by fixing the time of sunrise and sunset relay light 27) the ti photoperiod 32). The signals from the humidity sensor outside air 24 and the wind speed sensor 28 is coming to the unit 14 for determining the coefficient of heat loss, the results of which, together with the signals of the sensors solar radiation 25 and the ambient temperature 29 arrive at unit 9 measuring the natural temperature in the greenhouse. The results of calculations and output blocks 8 and 9 come to the comparator 11. If the natural temperature will be more optimal, then automatically turns on the ventilation system, and control system heating and heating are disabled by the relay element 1. If the natural temperature is less than optimal, the result of determining the natural temperature of the block 9 and the signal from the unit 8 calculates the optimal productivity of the temperature arrives at block 10 the definition of the discriminant, where previously entered through block 23 of the input coefficients of the production (from the same block of heat loss calculation 14). From the first output unit 10 a signal is supplied to the comparator 12, and the second output unit 10 and the output unit 9 to the adder 13, compute the optimal consumption temperature. In case of positive discriminant signal for comparing the element 2 of the first Comparators 11 and 12. Thus, for each discrete time interval computing unit 7 determines the optimal temperature. In addition, with the help of block 37, the optimum temperature is compared with the allowable input unit 23. If the optimum temperature would be more valid, then the switch 15 is served at the optimal temperature, if less, then it is permissible. Unit 23 records the duration of standing acceptable temperature and if it is greater than the predetermined (desired issued from block 23), instead of a valid switch 15 is temperature, optimal productivity.Automatic optimization, consisting of a sensor 6 internal temperature computing unit 7, the comparing element 2, amplifier 3, the actuator 4 and the regulator 5, supports this temperature for a selected period of time, after which the generator 18 clock pulses resets the result of the previous calculation and starts a new one. Clock 18 simultaneously controls the operation of the blocks 13, 8, 9 and 10. The role of clock and timer 30, which significantly reduces the system.Switching from DNEVNOY device 23 of the input data to the block 10 calculate the discriminant and the unit 8 calculates the optimal productivity of the temperature coefficients of the night model the values which are entered during setup. At the same time to the computing device 8 is connected to the device 22, the receiving signal from the averager 20 light and averager 21 daily temperature during the day period give private from division of the signals from the integrators 16 and 17 on the counter 19 pulses, running from the generator 18 clock pulses and relay 27 of the light.At the same time from the computing device disconnects the unit 14 to calculate the heat loss from the sensors 24 and 28, and solar radiation sensors 25 and light 26. The sensor 29 ambient temperature connected to a computing device constantly. Switch from night mode to day is similar to.The proposed method is implemented, for example, a device for calculating an optimum temperature, consisting of the following elements: a Central processor; two permanent storage devices ROM; RAM RAM decoder memory addresses; the address decoder input and output; timer with a quartz oscillator and controls; controls; indicators; device control sensors; termination device.The volume of programs recorded in the ROM will be 10 Kbytes, RAM 2 Kbytes.As timer and simultaneously gauge the age used BIS type KVI. Clock frequency, which determines the time specified crystal oscillator.All the sensors are in the form of independent modules, which are located at appropriate points greenhouses and performs the function of converting controlled environment settings into an electrical signal DC voltage in the range of 0.10 CenturyStandalone modules receive power control commands and generates information signals into a single channel of communication and power coaxial cable.Supply of sensors designed power module sensors, generating a frequency of 20 kHz.For control modules, sensors proposed controller module operating at a frequency of 250.375 kHz.As the temperature sensor is used, the resistance thermometer as sensors of indoor air humidity hygrometer design AFI; as the humidity sensor outdoor air system consisting of a dielectric square which was removals combination tachometric device on the bus.St. N 1140047 and optoelectronic on author.St. N 857882.The sensor arsenide-gallium solar cell, the solar radiation sensor battery Peltier elements.All sensors are equipped with normalizing converters with operational amplifiers COD or COD.However, instead of a hardware solution, it is possible to purely software.An example implementation of the method (optimization of the temperature regime growing cucumber variety "Moscow greenhouse").a) Let the sensors show the following values of measured value
E=21,1 klk; =80%in=22 days.op15 h; Tn30,5aboutC.Then the temperature optimal productivity
topt31,1aboutC.If the environmental parameters
tn-2,5aboutS; V 15 m/s; 80% Q 215 W/m2then the natural temperature in the greenhouse 22,5aboutC.The discriminant
D + -156,2 Because D < 0, the optimum energy does not exist and the system works when 31,3aboutC.b) Suppose the humidity At 60% Then
Let then the wind speed is 5 m/sThis natural temperature increases to
teat42,3aboutop9 o'clock Then topt30,6aboutC.Let tn-27,5aboutS; V 15 m/s; 80% Natural temperature is decreased to teat-2,5aboutC.D 99,2 > 0. Therefore, tOPTA24,4aboutWith that installed.As you can see, the optimal intensity of temperature on the 6aboutWith lower than optimal productivity that provides great savings warmth.C) Let E=10,5 klk; 80% in14 days.op15 h; Tn=19,5aboutWITH
Then topt18,9aboutC.At tn-27,5aboutS; V=15 m/s; 80% teat=-15,3aboutC.Since D 117,7 > 0, then tOPTA12,6aboutC.Since tOPTA< tSS14aboutTo set the temperature of the 14aboutC. If within three days the temperature rises, the system will switch to topt18,9aboutC. The METHOD of AUTOMATIC control of the TEMPERATURE IN the GREENHOUSE, including split period of growing plants at regular intervals, measuring in each of these periods of light flux density of solar radiation, ambient temperature, wind speed and humidity outside air, the determination of the results of these measure concentration with increasing first over the second turning on the heating system and maintaining its temperature, optimal productivity, otherwise the inclusion of the ventilation system, the adjustment of the mathematical model and its coefficients for transitions of day-night and night-day definition of the algorithm of the process model in the greenhouse the magnitude and sign of the discriminant, which characterizes the existence of a minimum energy consumption, and in the case of a positive determination of the optimal intensity, temperature, and change in accordance with the temperature setpoint knob, characterized in that it further determine the age of a plant, the duration of the photoperiod, humidity in the greenhouse, as well as the relative length of day and night, mentioned the value of a discriminant is determined from the expression
< / BR>where taboutpttemperature, optimal productivity;
tewithtthe air temperature in the greenhouse, which is installed in the absence of additional heating;
A22the regression coefficient of model efficiency in the square of the temperature in the greenhouse;
and optimal consumption temperature topt.efrom the expression
< / BR>and accordingly adjust for optimal productivity, temperature, and optimal optymalna temperature greater than the minimum allowed temperature of the air in the greenhouse, then set the optimum temperature, and if the optimum temperature less valid, then specify the allowable temperature, and when it reaches the last specified maximum term of its standing set temperature, optimal productivity.
FIELD: agricultural engineering.
SUBSTANCE: invention relates to device for control of microclimate in greenhouses. Proposed device is essentially closed space of greenhouse limited from one side by fragment of guard and by heat insulation from all other sides. Heating and measuring elements are installed inside. To protect measuring element from direct sun rays special screen is used. Control unit provides automatic control of device heating element and forms dc signal at its output corresponding to value of heat losses. Operation of device is based on measuring power of heater placed in closed space limited from one side by fragment of guard and at other sides by heat insulation. Heating element maintains is heated volume constant temperature equal to temperature maintained in zone of location of plants by means of automatic control system arranged in separate unit.
EFFECT: simplified design of device.
2 cl, 7 dwg
FIELD: lighting technology.
SUBSTANCE: light-emitting diodes (LED) with different radiation spectrum are used as light sources. Control unit input is connected to pulse frequency adjuster, dark pause adjuster and light pulse amplitude adjuster. Pulse shaper is represented as switch in LED circuit between common negative output and control unit. In second option of lighter design, light source housing is represented as strip along surface with plants and light sources having LED with different radiation spectrum separated along the strip. In third option of lighter design, surface with plants is represented with internal surface of cylindrical pipe. Housing with light sources is represented with several strips equally distanced from each other but with some space along forming surfaces. In fourth option of lighter design, surface with plants is represented with interior space of cylindrical pipe and pulse shaper is in the form of correct prism. Lighting method is a scanning of light flow from aligned LEDs with different radiation spectrum with sequential lighting of surface with plants.
EFFECT: possibility of light flow frequency, radiation spectrum, amplitude and beam form adjustment.
20 cl, 13 dwg
SUBSTANCE: vegetation installation comprises hollow cylindrical chamber and sources of light. Cylindrical chamber, dome roof, floor consist of external detachable transparent wall and inner stationary transparent wall. Sources of light are arranged as spotlight, are mounted between external detachable transparent wall and inner stationary transparent wall and are separated by vertical and horizontal partitions, forming sections shaped as squares. In the left upper corner of square-shaped section there are spotlight sources of blue light, and the right upper corner - spotlight sources of green colour, in the left lower corner - spotlight sources of red colour, in the right lower corner - spotlight sources of white colour.
EFFECT: such arrangement increases efficiency of installation due to uniform and controlled illumination.
SUBSTANCE: greenhouse plant cultivation period is broken down into several time intervals, the required rate of plant development and the adequate daily average temperature are specified. Each time interval is described by the light conditions: day or night. If the system has identified a daytime, then illumination, indoor air humidity, age of plants, photoperiod duration and relative daytime are measured. The average last-night temperature is calculated to derive the optimum producing temperature. If the system has identified a night-time, the average last-day temperature and the night temperature are determined. The estimated optimum producing temperature and night temperatures are corrected with observing the acceptable values.
EFFECT: higher accuracy of the fructification start time planning on the one hand and from the other hand, well developed and strong plants by the moment by photosynthesis intensification.
1 tbl, 2 dwg
SUBSTANCE: invention relates to agricultural machinery, namely to methods and systems of automatic control of temperature and light regime in greenhouses or other structures of a protected ground. The method includes splitting the vegetation period of plants in greenhouse at equal intervals, which duration an order of magnitude smaller than the constant time of the most high-velocity perturbation, calculation for each time interval of optimum temperature and this optimal temperature maintenance constant during the whole period of time. Then the air humidity, air temperature and illumination in the greenhouse are measured to obtain signals from the sensors of air, temperature and light, respectively, the age of plants are measured to obtain a signal from the counter device of plant age, at that these data enter the computer set point adjuster which calculates the average night temperature, then determines and sets the multidimensional optimum daily temperature at the criterion of productivity in the greenhouse.
EFFECT: invention enables to improve significantly the efficiency of light energy use and to increase productivity of plants themselves.
SUBSTANCE: invention relates to agricultural machinery, namely to methods and systems of automatic control of light and temperature and humidity regime in greenhouses or other structures of protected ground. Automatic control system for light and temperature humidity regime in a greenhouse, which is carrying out the claimed method, contains a control circuit of temperature in a greenhouse, including a temperature sensor, whose output is connected with the object of regulation by the comparing element with a set point adjuster, signal multiplier of the current and the calculated temperature disagreement, as well as an actuating mechanism maintaining in the facility the calculated temperature, and the computer unit which calculates the optimum temperature. At that the system also provides additional control loops of lighting and humidity in a greenhouse.
EFFECT: invention enables to ensure the autonomy of temperature, air humidity adjustment inside the greenhouse and of operation of supplementary lighting equipment independently of each other, although at that their mutual influence on plant productivity remains.
SUBSTANCE: invention relates to agricultural machinery, namely to methods and systems for automatic control of temperature and light modes in greenhouses or other structures of a protected ground. Automatic control system for temperature and light regime in greenhouse, implementing the claimed method, contains the control loop of temperature in a greenhouse, including a temperature sensor which output is connected with the object of regulation through the comparing element with the adjuster, a signal multiplier of maladjustment the current and the calculated temperatures, as well as an actuator supporting at the facility the calculated temperature, as well as the computing unit, which calculates an optimum temperature. Also the system contains an additional control loop of lighting.
EFFECT: invention enables to improve accuracy of maintaining temperature and lighting in cultivating area and stability of the system operation, as well as increase efficiency of photosynthesis mechanism in plants due to adjustment of such environmental factors as temperature and irradiance.
SUBSTANCE: system to grow potato plants to produce microtubers comprises chambers with automatically controlled medium to keel and maintain growth of potato plants for the whole life cycle. Each chamber has facility of air temperature control, facility of atmospheric humidity control, illumination facility, sensors of temperature, moisture and light, facility for delivery of nutrients and water to plants. System includes computer facility for continuous automatic monitoring and control of facilities of lighting, air temperature and atmospheric humidity control, and also facilities for delivery of nutrients and water. It is possible to grow both sprouts of tissue culture into mother plants, as well as hefts of mother plants into minitubers, which may be used as source of seeds for further reproduction in the field as stocks of seed potato.
EFFECT: using system with controlled conditions of medium and method providing for optimal conditions of cultivation, results in quick growth and development of potato piece, so that up to six harvests of tubers may be gathered in a calendar year.
18 cl, 8 dwg
SUBSTANCE: device of automatic control of mist-generating plant relates to gardening, namely to vegetative propagation of horticultural crops by the method of herbaceous cuttings. The device comprises operating mode switches on the number of units of mist-generating plant, a commutation switch to connect the power source to the units of mist-generating plant and cyclical timing relay that determines the duration of the presence or absence of each unit power. The cyclical timing relay consists of a microcontroller, a real-time clock, a memory module, two encoders, control buttons and an alphanumeric LCD display.
EFFECT: device of automatic control of mist-generating plant provides optimisation of watering mode by an independent set of time of watering and the time of pause separately for several intervals within the day, such as morning, day, evening and night.
SUBSTANCE: light diode radiator comprises a body from a heat conductive material, at least partially ribbed at the rear side. The body has an outlet hole, which is closed with an optically transparent protective glass or a diffuser. Inside the body there are linear boards installed with assembled groups of light diodes with a different spectrum of radiation in the range of spectral efficiency of photosynthesis /400-700 nm/ with optical axes, facing the outlet hole of the body, and connected to a source of supply. At least on two internal side walls of the concave body there is a cascade of longitudinal plates forming terraces from a heat conductive material, which create ribs of an internal radiator of a conductive heat sink. Longitudinal plates are in thermal contact with body walls and face the outlet hole with a flat part. On each plate there are linear boards /lines/ installed in thermal contact, mostly boards with an aluminium base with high-capacity light diodes or light diode modules, or separate light diodes, which are connected in series or in parallel-serial chains to a source of supply.
EFFECT: design will make it possible to improve thermal and spectral characteristics, to increase density of radiation flow with reduced dimensions of a radiator.
6 cl, 7 dwg