WO1997046834A1 - Systeme de regulation a surete integree en reseau pour unites de ventilation - Google Patents

Systeme de regulation a surete integree en reseau pour unites de ventilation Download PDF

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Publication number
WO1997046834A1
WO1997046834A1 PCT/CA1997/000373 CA9700373W WO9746834A1 WO 1997046834 A1 WO1997046834 A1 WO 1997046834A1 CA 9700373 W CA9700373 W CA 9700373W WO 9746834 A1 WO9746834 A1 WO 9746834A1
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WIPO (PCT)
Prior art keywords
slave controller
master controller
controller
temperature
slave
Prior art date
Application number
PCT/CA1997/000373
Other languages
English (en)
Inventor
Francois Routhier
Original Assignee
Monitrol Inc.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Monitrol Inc. filed Critical Monitrol Inc.
Priority to AU28840/97A priority Critical patent/AU2884097A/en
Priority to EP97922792A priority patent/EP0906547A1/fr
Publication of WO1997046834A1 publication Critical patent/WO1997046834A1/fr

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/0001—Control or safety arrangements for ventilation
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/30—Control or safety arrangements for purposes related to the operation of the system, e.g. for safety or monitoring
    • F24F11/32—Responding to malfunctions or emergencies
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/62—Control or safety arrangements characterised by the type of control or by internal processing, e.g. using fuzzy logic, adaptive control or estimation of values
    • F24F11/63—Electronic processing
    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
    • G05B9/00—Safety arrangements
    • G05B9/02—Safety arrangements electric
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/30—Control or safety arrangements for purposes related to the operation of the system, e.g. for safety or monitoring
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/50—Control or safety arrangements characterised by user interfaces or communication
    • F24F11/54—Control or safety arrangements characterised by user interfaces or communication using one central controller connected to several sub-controllers
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/70—Control systems characterised by their outputs; Constructional details thereof
    • F24F11/72—Control systems characterised by their outputs; Constructional details thereof for controlling the supply of treated air, e.g. its pressure
    • F24F11/74—Control systems characterised by their outputs; Constructional details thereof for controlling the supply of treated air, e.g. its pressure for controlling air flow rate or air velocity
    • F24F11/77—Control systems characterised by their outputs; Constructional details thereof for controlling the supply of treated air, e.g. its pressure for controlling air flow rate or air velocity by controlling the speed of ventilators
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F2110/00—Control inputs relating to air properties
    • F24F2110/10—Temperature
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B30/00—Energy efficient heating, ventilation or air conditioning [HVAC]
    • Y02B30/70—Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating

Definitions

  • TITLE FAIL-SAFE NETWORKED CONTROL SYSTEM FOR VENTILATION UNITS.
  • the present invention relates to air conditioning control ana, -nore particularly, to a networked ventilation on rcl system sufficiently rooust to maintain ⁇ nimai environmental conditions m an enclosure upon occurrence of a nardware failure or software problem that renders the network inoperative.
  • the ventilation control system _s particularly useful for intensive livestock farms were adequate supply of fresn air is critical to avoi ⁇ massive livestock ⁇ estruction.
  • Intensive livestock farms designed for the breeding and production of poultry, pork, veal and other animals intended for human consumption have very stringent air quality requirements.
  • the population density in those farms is such that fresh a r must be continuously supplied to evacuate noxious gases such as ammonia and carbon dioxide.
  • the supply cf fresh air also reduces the humidity levels ana lowers the temperature of the enclosure. Failure to maintain adequate environmental conditions, even for snort perio ⁇ s, may resu.t in massive livestock destruction. The danger is particularly severe during the summer period, when the amoient temperatures are high. If the ventilation system cf the farm ceases functiomn ⁇ the temperature and the concentration of noxious gases increases rapidly to reach fatal concentration levels.
  • the slave controllers are individually addressable to enable the master controller to transmit data to each slave unit cf the group.
  • the master controller can thus set eacn fan to rotate at a predetermir.e ⁇ speed, which, determines the quantity of fresn a r introduced m the enclosure or extracted from the enclosure. More specifically, the speed setting proce ⁇ ure consists of impressing on the communication link a variable frequency signal, the frequency being indicative of the speed of the fan.
  • the addressed slave controller receives that signal, the data is stored in a local register.
  • the slave controller continuously observes the speed of rotation of the fan and compares it with the set point. If a ⁇ eviation is noted, the slave controller a ⁇ justs the voltage impresse ⁇ across the excitation win ⁇ ing of the electric motor A tne fan to maintain the actual fan speed as close as possible to the set point.
  • the m ⁇ ividual fan units are ⁇ esigr.e ⁇ to continue operating based on the last spee ⁇ set point.
  • this approach donates to the system a fail-safe capability by maintaining the operation of the fan units even when the network crashes.
  • the system may not always be a ⁇ le to provide sufficient supply cf fresh air to avoid massive ⁇ estruction of livestoo: in such conditions.
  • An obj ect of the invention s to provide a ventilation system with averts the drawoao:s c f the prior art devices .
  • the invention provides a ventilation control system, comprising: - a master controller; - at least one slave controller, said slave controller including a temperature sensor generating an output signal representative of a temperature in a vicinity of said sensor; a communication link between said master controller and said slave controller allowing said master controller ana said slave controller to exchange data; - said slave controller including control means for varying a rotational speed of a fan unit associated with said slave controller at least partially in relation to said output signal.
  • the ventilation system in accordance with the invention includes a master controller and a plurality of slave controllers connected to one another over the communication link.
  • the master controller generates control parameters that are transmitted to the individual slave controllers so they can regulate the operation of the associated fan units at least in partial dependence upon the control parameters.
  • Each slave controller can adopt several modes of operation. In one specific mode the master controller issues a temperature set point cn the basis of which the slave controller will regulate the speed of the fan. The regulation also takes into account the output signal generated from the local temperature sensor. On the basis of the temperature difference between the set point and the actual temperature value the slave controller will adjust the speed of the fan as to reduce the error between the two values. In a different mode cf operation the master controller issues a rotational speed set point enforced locally by the slave controller. More specifically, the slave controller measures the actual speed of the fan and regulates the voltage across the excitation winding to adjust for errors.
  • the slave controller can still regulate the operation of the fan based on the output of the local temperature sensor. Th s provides the slave controller with the ability to react to local temperature changes and adjust the speed cf the fan accordingly.
  • the invention further provides a ventilation control system, comprising: - a master controller; - at least one slave controller, said slave controller including a temperature sensor generataing an output signal representative of a temperature in a vicinity of said sensor; - a communication link between said master controller ana said slave controller allowing said master controller and said slave controller to exchange data; - said master controller including means for generating at least one control parameter that is transmitted to said slave controller over said communication link; - said slave controller including control means for varying a rotational speed of a fan unit associated with said slave controller at least partially m relation to said control parameter; and - said slave controller being capable of transmitting to said master controller data related to said output signal and representative of a temperature in a vicinity of said temperature sensor; and - said master controller including means for processing said ⁇ ata related to said output signal and for generating a new control parameter for transmission to said slave controller.
  • the master controller is preferably designed to read the temperature remotely as measured by the temperature sensor of the slave controller, thus it can continue to issue valid control parameters shoui the temperature sensor cf the master controller fails.
  • the remote reading operation is effected by transmitting a command to the slave controller to put on the communication link the value in the register that contains the current output of the temperature sensor. Such reading can be affected a number of times within a predetermined time period, this allowing the master controller to follow the evolution of the temperature over time a ⁇ equately.
  • the master controller can rea ⁇ the temperature from several slave controllers. The received data can then ce averaged out or otherwise mathematically processed to provide a more accurate indication of the temperature in the enclosure.
  • FIG. 1 s a block diagram of a ventilation system in accor ⁇ ance with the present invention
  • FIG. Z s block diagram of a master controller of the ventilation system snown in Figure 1
  • - Figure 3 is a block diagram of a slave controller of the ventilation system shown m Figure 1
  • - Figure - is a diagram illustrating the methc ⁇ of fan spee ⁇ control impiemente ⁇ by the slave controller
  • - Figure 5 is a diagram showing the strategy enforced by the slave controller for regulating the speed of the fan on the basis of local temperature if there is a malfunction of the master controller
  • - Figure 6 is diagram showing the strategy enforced by the slave controller for regulating the speed of the fan under normal operating conditions.
  • FIG. 1 DESCRIPTION OF A PROFFERED EMBODIMENT Figure I of the annexed drawings illustrates a fail- safe ventilation system particularly well suited for use in intensive livestock f rms.
  • the ventilation system features the capability of maintaining an adequate supply of fresh air when a malfunction of one or more of its components occurs, such as an interruption of the communication I ⁇ n ⁇ , a har ⁇ ware failure of the master controller or a software problem in the master controller.
  • the ventilation system includes a control section comprising a master controller 10 connected to a plurality cf slave controllers 12, 14, 16 and 18 by a communication link 19.
  • a control section comprising a master controller 10 connected to a plurality cf slave controllers 12, 14, 16 and 18 by a communication link 19.
  • four slave controllers are use ⁇ . This is only a question of design as the memoer of slave controllers may vary without departing from the spirit of the invention.
  • Each slave controller regulates the operation of a fan unit that includes an electric motor driving a mechanical device for producing currents in order to circulate, exhaust, or deliver large volumes of air.
  • Such mechanical device may be in the form of a rotating paddle wheel, an air screw, with or without a casing or a positive displacement pump including meshing lobes rotating inside a casing to transport volumes of air from the inlet to the outlet.
  • the rate at which a fan unit displaces air is dependent upon the speed of rotation of the electric motor.
  • the slave controller can thus regulate the operation of the fan unit by varying the speed at which tne electric motor turns. This 10 achieve ⁇ by controlling tne voltage impresse ⁇ across the excitation winding of the electric motor. Usually, the higher the voltage the faster the motor will rotate.
  • the function of the master controller 10 is to enforce a global ventilation strategy cy transmitting to the individual slave controllers operational set points, either m terms cf rotational spee ⁇ or local temperature.
  • the slave controllers enforce those set points in order to implement the global strategy.
  • the master controller 10 includes a CPU 28 connected to a memory 30 through a bus 32.
  • the memory 30 contains the instructions of the program executed by the CPU. It also has a reserved portion for storing data such as variables or parameters that the program calculates during its execution. Most preferably the memory 30 is non volatile to avoid loss of data when the power is turned off. This avoids the requirement of reloading the program every time the unit is energized and also allows to retain the current status of all variables and parameters m the event of a sudden power loss. Thus, when the master oontrciier is re-energized it can continue operating m the same state at which the power loss occurred.
  • the CPU 23 can read the outside temperature by observing the output of a temperature sensor 34.
  • the sensor 34 generates an analog output supplied to an analog/digital converter 36 that, n turn, feeds the digitized information to a register 33.
  • the latter reads the information stored in the register 38.
  • the CPU 28 calculates temperature or rotational speed set points that are successively transmitted to the individual slave controllers.
  • the set points data is written into a register 40 before being sent in serial 1 form over the communicaticn link 19. That same register
  • the controller comprises a CPU 0 42 connected to a non volatile memory 44 through a bus 1 46.
  • a number cf interfaces are connected to the bus 46 to 2 allow the CPU 42 to exchange data with external devices.
  • 3 External block 48 designates an AC current power supply 4 that, typically, would be the main power transmission
  • the CPU 22 enable the CPU to detect the zero crossing points.
  • This 23. information gives the CPU a reference point to calculate the firing angle of a bilateral gate controlled rectifier (Triac) used for regulating the voltage impressed across the excitation winding of the electric motor. This characteristic will be described in greater detail later.
  • Triac bilateral gate controlled rectifier
  • the line voltage is also applied to a power supply unit 54 that steps the voltage down and rectifies it to provide a stable source of DC power sufficient to energize the electronic components of the slave controller.
  • the clock 56 represents the bilateral gate controlle ⁇ rectifier used for regulating the excitation voltage, hence the speed of the fan unit. To achieve the highest possible speed the maximum voltage is applied to the excitation winding. This is accomplished by sending to the gate controlled rectifier a pulse that coincides with the zero crossing of the line voltage.
  • the CPU 42 issues a pulse by loading a register 58 with a certain value that is then passed to a digital/analog converter, transforming the digital value into an analog pulse directed to the bilateral gate controlled rectifier.
  • the excitation voltage can be reduced by delaying the actuationmodule by a predetermined angle. Thus, instead of issuing a pulse that almost coincides with the zero crossing, the pulse is delayed by an angle that depends upon the desired fan speed.
  • the value of the delay angle is adjusted continuously cy the CPU on the basis data supplied by sensor 60 that s indicative cf the rotational speed of the electric motor.
  • the speed sensor 60 is a Hall- effect device including one or more magnets secured to the rotor of the electric motor.
  • a Hail-effect sensor is mounted to the casing cf the electric motor and it is periodically swept by the magnetic field generated by the magnets.
  • the latter issues a pulse that is received by a counter 62.
  • the counter 62 totalises the number pulses over a predetermined period of time say 500 milliseconds. At the expiration of this period the total number of pulses is loaded into a register 64 where it can be read by the CPU 42.
  • the CPU 42 can correct the ⁇ elay angle of the firing pulse applied to the bilateral gate controlled rectifier m order to adjust for any difference oetween the actual speed and the programme ⁇ speed.
  • This procedure could be implemented by comparing the actual speed of rotation with the speed set point to ⁇ erive an error value.
  • the magnitude of the error value rnen determines how much correction to be made cn the f ⁇ n ⁇ angle delay.
  • This fee ⁇ bac loop is particularly iseful as it allows to maintain the speed constant, even when strong winds are present that generate currents Having the effect of either accelerating or decelerating the fan.
  • the actual spee ⁇ of the fan may vary significantly with relation to the desired speed, ⁇ ependmg upon the prevailing wind conditions.
  • a temperature measurement device such as a thermistor, represented by the bloc ⁇ 66 is mounted to the casing of the electric motor to sense any overneatmg of the motor.
  • the output of the thermistor 66 is digitized by the analog/digital converter 68 and the resulting value is loaded in register 70 wnere it can be read by the CPU 42.
  • the CPU 42 is programmed to take action primary to avoid permanent damage to the electric motor. Such action depends upon the particular strategy to be enforced. For instance the operation of the motor could be interrupted until it has cooled down sufficiently so its operation can be resumed. .Another possibility is to reduce the speed of the motor so ventilation is maintained by the fan unit while overneatmg of the motor is controlled.
  • Temperature sensor 2 is provided to measure the ambient temperature in the vicinity of the fan unit.
  • the output signal generated by the sensor 72 is digitized by analog/digital converter 74 and the resulting value written in the register 76 so that it can be accessed by the CPU 42.
  • the temperature sensor 72 is an important input device as it enables the fan unit to modulate its spee ⁇ with relation to temperature even when the communication with the master controller 10 is lost. This feature will be discussed in more detail later.
  • the slave controller is provided with a register 78 m which is stored data transmitted over the communication link 19, so it can be accessed by the CPU 42.
  • the register ⁇ 8 is used to receive ⁇ ata from tne CFU 42 that s to be sent over the link 19.
  • a slave controller based on a micro controller manufactured by MICROCHIP under the product number PIC16C622 has been found satisfactory.
  • the communication protocol between the master controller 10 and the individual slave controllers is base ⁇ on the current loop standard that is implemented by having the link consist of a loop that carries a current with a magnitude when it is in a mark (1) state i.e., logic level 1 is being signalled and does not carry current when it is in a space (0) state i.e., logic level 0 is being signalled.
  • Data is exchanged between the master controller and the slave controllers as
  • Each packet would typically include a start bit, 8 data bits followe ⁇ by one, one and a half, or two stop bits.
  • the slave controller can be installed either outside of tne electric motor or inside the casing thereof. An internal installation is preferred.
  • the master controller Before initiating the operation cf a particular fan unit the master controller transmits to the associate ⁇ slave controller a configuration data set that determines the mode of operation of the slave controller and also loa ⁇ s certain register with default values.
  • the proce ⁇ ure for writing ⁇ ata m a register of the slave controller is a two pass operation effected by transmitting twice a configuration data set. The first pass begins by sen ⁇ mg the following data set:
  • the start byte is a header that signals the addressed device the beginning of a data set.
  • the following identi cation oyte is essentially an address that uniquely identifies the slave controller. An identification byte of 3 bits allows 256 different address combinations.
  • the command byte signals the slave controller that data will be written into one of its registers. The address of the register to be loaded is provided by the address byte. The next byte is the data byte that is the actual information stored in the register.
  • the configuration data set ends t; a checksum byte provided for data validation.
  • the followin ⁇ registers of the slave controller can be configured through a configuration data set. Those registers are essentially memory locations in the physical memory 44 and they are different from the registers 52, 58, 64, 70, 76 ana ⁇ 3 descnoea earlier.
  • Register PO contains the speed set point of the fan. Typically, the number loaded by the master controller is expressed in revolutions per minute in steps of 20 rpm. For example a speed setting of 50 would mean 1000 rpm.
  • Register PI contains the temperature set point expressed 5 either m terms of degrees Celsius or Fahrenheit, 6 depending upon the value of a bit in the configuration
  • Bit No. 7 of the configuration byte P3 designates 8 the units of temperature in which the temperature set point is expressed, either Fahrenneit or Celsius.
  • Bit 5 indicates whether the fan is allowed to attain its maximum speed determined by the structural capability of the electric motor, f this bit is 0, the speed is limited to the value stored in the register P7, otherwise full voltage can be applied across the excitation winding.
  • Bit No. 3 and No. 2 determine the mode of operation of the slave controller m the event a malfunction _s determined to exist with the master controller or with the communication link 19. Such determination is made upon occurrence of either one of the following events:
  • Th s means that no data packets are being sent by the master controller which can be the result of a hardware failure, such as the wiring m the communication link 19 being interrupted, or a software problem causing the master controller to hang up;
  • the slave controller will rely cn the output of temperature sensor 72 to modulate the speed of the fan.
  • This s accompi snec by ca ⁇ n ⁇ into account the default temperature stored in register P6, the temperature ⁇ ifferential stored in the register P 13 and the minimum fan speed stored in register P 14.
  • Figure 5 of the annexed drawings illustrates this feature.
  • the values stored in registers P6 and P6 + P13 define a range of temperature over which the speed of the fan is varied on the basis of the signal received from temperature sensor 72.
  • wnen the local temperature corresponds to the value P6 + P13 the fan is rotating at the maximum speed.
  • spee ⁇ /temperature over the range ? 13 is linear. It should be noted that the speed of the fan never goes below the value stored m register P14 even when the temperature reported by the sensor 72 drops below the value stored in P6.
  • mode A If mode A is set then the fan will imme ⁇ iately stop when a con ⁇ ition of malfunction is detected. In mode 10 the fan will continuously rotate at the ⁇ efault speed setting stored m register P 5. Mode 11 is a continuation of the normal operation under mode 00, described below. The slave controller will simply continue to enforce the last temperature setting received from the master controller.
  • mode 00 the speed of the fan is a linear function of the temperature measured by the local sensor 72 over a range determined by the temperature set point stored in register P 1 and the temperature differential value stored m register P 13, taking also nto account the minimum fan speed m register P 14.
  • This relationship is best shown in figure 6. It will be noted that the graph s similar to figure 5 with the exception that the base temperature value (P 1 ⁇ is not fixed and fluctuates in accordance with the control strategy implemented by the master controller. Thus, the line segment that defines the relationship spee ⁇ /temperature moves norizontally along the temperature axis as the temperature set point m the register P 6 is changed by the master controller. Also note that the speed of the fan can never drop under the value stored in the register P 14.
  • Mode 01 is identical to mode 0C described above with the exception that when the temperature drops below the temperature set point m register P 1 the speed cf the fan will be controlled on the basis of the values stored in the registers P 8 and P 9.
  • P 8 determines the duration of the operational cycle of the fan that includes an on segment during which the fan operates and an off segment during the fan is idle. The ⁇ uration of the off segment is determined by the value stored in P 9. Thus, if P 8 specifies a time period of say 5 minutes and P 9 (duty cycle) is of 50f a fan will operate over two and a half minutes and remain dle for two and a half minutes. The operating cycle then repeats itself indefinitely.
  • Mode 10 does not take m consideration the output of the temperature sensor 72 and operates the fan on the basis of the speed set point stored m register PO.
  • the value store ⁇ in the register P 0 ⁇ s an initial spee ⁇ ; that spee ⁇ is then progressively reduced on the basis of the reduction rate stored in the register P10. finally, during mode 11 the speed of the fan is held constant at the set point m register PO.
  • the specific procedure for setting up anyone of the registers P 0 to P 14 is to generate over the communication link 19 the con iguration ⁇ ata set of Table 1, where the register address byte is the address of the register to be loaded and the data byte contains the actual data to be stored m that register.
  • the slave controller responds to the master controller by sending back a number of parameters allowing the master controller to compare the response with the configuration data set to ensure that a valid transmission has taken place.
  • Table 4 describes the response generated by the slave controller.
  • the first pass of the configuration of the particular register is considered complete.
  • the second pass is essentially a duplication of the first pass with the exception that the header byte of the data set transmitted by the master controller is different to allow the slave controller to determine that a second writing pass is taking place.
  • the value loaded in the register may be copied in a non-volatile portion of the memory so the data will not be lost m the event of a sudden power disruption.
  • the second pass writing operation is completed by the transition from the slave controller to the master controller of the data set in figure 4. If the data set is correctly received by the master controller, the latter assumes that the register configuration operation has been correctly implemented.
  • the slave controller contains a numoer of status registers in which is stored information relating to the current operative condition of the controller and also data generated by external sensors.
  • the master controller can interrogate the slave controller to read the information in anyone of those registers. The information thus obtained can be used to compensate for malfunctions of the slave controller (for instance the master controller can increase the spee ⁇ cf the remaining fan units), or remotely rea ⁇ temperature, among others.
  • Table 5 below describes the various status registers of the slave controller. Some of those registers correspond to the registers 52, 58, 64, 70, 76, or 78, while others are memory locations in the pnysical memory 44 which can be individually addressed by the CPU 42.
  • Register VO corresponds to register 64 that contains the value of the actual speed of rotation of the fan.
  • Register V I on the other han ⁇ contains the speed setting that has been generated by the master controller.
  • register V 1 could be the same memory location has register PI.
  • Register V2, correspon ⁇ s to register 66 ana contains a thermal flag that is raised when the temperature of the motor exceeds a preset value. This enables the srave controller to stop the operation of the motor so it cools ⁇ own.
  • a number of possible strategies can be implemented, depending upon the degree of overheating. If the overheating is severe, the motor may be stopped altogether. In mild overneati ⁇ conditions, the speed of the motor may oe re ⁇ uce ⁇ .
  • the register V2 also allows the master controller to be aware of the overheating condition. This enables the master controller to implement a compensating strategy m order to maintain the supply cf fresh air m the enclosure substantially constant. This strategy may consist, for example, of increasing the spee ⁇ cf the remaining fan units. If desire ⁇ , the task of controlling the overneating condition may be left entirely with the master controller in which case the master controller could either command the fan to stop or reduce its speed by loading the appropriate speed setting in the register PO. It is preferred, however to provide the slave controller with a software capability to respond to an overheating event so the response is available even when the communication with the master controller is lost.
  • the register V3 contains a number of flags designed to signal malfunctions of external sensors. Bit number 7, indicates that the slave controller is operating in the default mode due to a communication time out or to an absence of current in the communication loop. Bit No. 5 signals malfunctions of the speed sensor. The occurrence of a malfunction is determined when the spee ⁇ varies more than 50% over 1/8 revolution. Finally, bit No. 4 signals malfunctions of the temperature sensor 72. A malfunction is determined wnen the temperature abruptly rises or drops by more than 10%.
  • Register 24 contains the temperature output signal from the sensor A.
  • the master controller To read the data stored m a given status register the master controller issues the following command that is represented by the data set of figure 6:
  • the slave controller will place on the communication link 19 the data contained in the four consecutive status registers beginning at the ⁇ esignated address at the fourth byte of the communication data set.
  • the response of the slave controller is provided in the Table 7 below:
  • Allowing the master controller to consult the status registers of the slave controller is important because it provides certain security benefits such as when the temperature sensor associated with the master controller is malfunctioning. In those instances, the master controller can effect a remote temperature reading operation and continue to manage the entire system based on the temperature backup data supplied from the sensor 72. Typically, the remote temperature reading would be affected at regular intervals in order to follow the temperature evolution. In an installation where several slave controllers are provided with a local temperature sensor it could be envisaged to remotely read the temperature from several sources and average out the measurements to provide a more accurate indication of the temperature in the enclosure.

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  • General Engineering & Computer Science (AREA)
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  • Control Of Temperature (AREA)

Abstract

Le système de ventilation de la présente invention comprend un régulateur central (10) relié par des liaisons de télécommunication à des régulateurs auxiliaires (12, 14, 16, 18) qui régulent le fonctionnement d'unités de ventilation individuelles (20, 22, 24, 26). Le régulateur central (10) transmet aux régulateurs auxiliaires (12, 14, 16, 18) des valeurs de consigne de réglage de température ou de vitesse de rotation calculées de manière à maintenir des conditions ambiantes désirées à l'intérieur de locaux. Au moins un régulateur auxiliaire (12, 14, 16, 18) est muni d'un capteur de température (72) qui permet au dit régulateur auxiliaire de moduler la vitesse du ventilateur en fonction de la température locale. Cette caractéristique est utile dans les situations où le régulateur central (10) n'est plus en mesure de transmettre des données de valeur de consigne de réglage valides au régulateur auxiliaire (12, 14, 16, 18) en raison d'une défaillance dudit régulateur central (10) ou parce que la liaison de télécommunication est interrompue. Le capteur de température local (72) peut également être utilisé comme dispositif de réserve du capteur de température principal (34) du régulateur central (10). Au cas où le capteur de température principal (34) tombe en panne, le régulateur central lit la température à distance au moyen de la liaison de télécommunication et utilise cette donnée pour continuer à produire des données de valeur de consigne de réglage qui sont transmises aux régulateurs auxiliaires.
PCT/CA1997/000373 1996-05-31 1997-05-29 Systeme de regulation a surete integree en reseau pour unites de ventilation WO1997046834A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
AU28840/97A AU2884097A (en) 1996-05-31 1997-05-29 Fail-safe networked control system for ventilation units
EP97922792A EP0906547A1 (fr) 1996-05-31 1997-05-29 Systeme de regulation a surete integree en reseau pour unites de ventilation

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CA002177941A CA2177941A1 (fr) 1996-05-31 1996-05-31 Systeme de regulation reseaute a surete integree pour appareils de ventilation
CA2,177,941 1996-05-31

Publications (1)

Publication Number Publication Date
WO1997046834A1 true WO1997046834A1 (fr) 1997-12-11

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AU (1) AU2884097A (fr)
CA (1) CA2177941A1 (fr)
WO (1) WO1997046834A1 (fr)

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WO2002004871A2 (fr) * 2000-07-07 2002-01-17 Convec Aps Dispositif de ventilation et batiment comportant un tel dispositif de ventilation
EP1182407A2 (fr) * 2000-08-19 2002-02-27 Lampe & Martens Gebäudetechnik Gmbh & Co. KG Dispositif pour la commande et/ou la surveillance des conditions climatiques dans un bâtiment
US6624394B2 (en) * 2002-01-28 2003-09-23 Hp Intellectual Corp. System for obtaining a uniform air temperature in a discrete space
EP1482253A3 (fr) * 2003-05-21 2010-01-13 Buva Rationele Bouwprodukten Bv Méthode et dispositif pour la ventilation d'un local
DE102008041463A1 (de) 2008-08-22 2010-02-25 Robert Bosch Gmbh Steuersystem und Steuerverfahren zum Steuern einer Mehrzahl von Antriebsquellen eines Hybridantriebs
US7883023B1 (en) * 2007-01-29 2011-02-08 Hewlett-Packard Development Company, L.P. Fluid moving device having a fail-safe operation
ES2367503A1 (es) * 2009-03-24 2011-11-04 Sociedad Inversiones De Las Cinco Villas 2008, S.L. Sistema de gestión ambiental de explotaciones ganaderas, avícolas y similares.
CN104197480A (zh) * 2014-09-10 2014-12-10 广州文冲船厂有限责任公司 一种随动式空调通风控制系统及其运行方法
FR3007827A1 (fr) * 2013-06-28 2015-01-02 Andre Amphoux Dispositif de commande d'au moins un dispositif de ventilation parametrable.
GB2473916B (en) * 2009-09-23 2015-04-08 Ebm Papst Uk Ltd Fan control systems
EP3361170A4 (fr) * 2015-10-28 2018-10-24 Huawei Technologies Co., Ltd. Procédé et appareil d'ajustement de climatisation au niveau d'une pièce, et dispositif de commande
CN110397616A (zh) * 2019-08-12 2019-11-01 珠海广通汽车有限公司 散热风扇控制方法、散热系统及高压电源分配箱
CN112165422A (zh) * 2020-09-28 2021-01-01 浙江启扬智能科技有限公司 一种一主多从温度控制系统及地址自动匹配方法
CN113728202A (zh) * 2019-04-15 2021-11-30 大金工业株式会社 风机单元、风机单元系统以及空气处理系统

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US10537041B2 (en) * 2016-08-22 2020-01-14 Asia Vital Components Co., Ltd. Heat dissipation system with air sensation function
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CN109442677B (zh) * 2018-09-18 2022-09-09 平安科技（深圳）有限公司 空调系统的故障控制方法、电子设备

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Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2002004871A3 (fr) * 2000-07-07 2002-09-26 Convec Aps Dispositif de ventilation et batiment comportant un tel dispositif de ventilation
US6990825B2 (en) 2000-07-07 2006-01-31 Danfoss A/S Ventilating device and a building comprising such a ventilating device
WO2002004871A2 (fr) * 2000-07-07 2002-01-17 Convec Aps Dispositif de ventilation et batiment comportant un tel dispositif de ventilation
EP1182407A2 (fr) * 2000-08-19 2002-02-27 Lampe & Martens Gebäudetechnik Gmbh & Co. KG Dispositif pour la commande et/ou la surveillance des conditions climatiques dans un bâtiment
EP1182407A3 (fr) * 2000-08-19 2002-07-24 Lampe & Martens Gebäudetechnik Gmbh & Co. KG Dispositif pour la commande et/ou la surveillance des conditions climatiques dans un bâtiment
US6624394B2 (en) * 2002-01-28 2003-09-23 Hp Intellectual Corp. System for obtaining a uniform air temperature in a discrete space
EP1482253A3 (fr) * 2003-05-21 2010-01-13 Buva Rationele Bouwprodukten Bv Méthode et dispositif pour la ventilation d'un local
US7883023B1 (en) * 2007-01-29 2011-02-08 Hewlett-Packard Development Company, L.P. Fluid moving device having a fail-safe operation
DE102008041463A1 (de) 2008-08-22 2010-02-25 Robert Bosch Gmbh Steuersystem und Steuerverfahren zum Steuern einer Mehrzahl von Antriebsquellen eines Hybridantriebs
ES2367503A1 (es) * 2009-03-24 2011-11-04 Sociedad Inversiones De Las Cinco Villas 2008, S.L. Sistema de gestión ambiental de explotaciones ganaderas, avícolas y similares.
GB2473916B (en) * 2009-09-23 2015-04-08 Ebm Papst Uk Ltd Fan control systems
FR3007827A1 (fr) * 2013-06-28 2015-01-02 Andre Amphoux Dispositif de commande d'au moins un dispositif de ventilation parametrable.
CN104197480A (zh) * 2014-09-10 2014-12-10 广州文冲船厂有限责任公司 一种随动式空调通风控制系统及其运行方法
EP3361170A4 (fr) * 2015-10-28 2018-10-24 Huawei Technologies Co., Ltd. Procédé et appareil d'ajustement de climatisation au niveau d'une pièce, et dispositif de commande
US10670294B2 (en) 2015-10-28 2020-06-02 Huawei Technologies Co., Ltd. In-room air conditioner adjustment method, apparatus, and controller
CN113728202A (zh) * 2019-04-15 2021-11-30 大金工业株式会社 风机单元、风机单元系统以及空气处理系统
CN113728202B (zh) * 2019-04-15 2023-03-17 大金工业株式会社 风机单元、风机单元系统以及空气处理系统
CN110397616A (zh) * 2019-08-12 2019-11-01 珠海广通汽车有限公司 散热风扇控制方法、散热系统及高压电源分配箱
CN112165422A (zh) * 2020-09-28 2021-01-01 浙江启扬智能科技有限公司 一种一主多从温度控制系统及地址自动匹配方法
CN112165422B (zh) * 2020-09-28 2023-03-10 浙江启扬智能科技有限公司 一种一主多从温度控制系统的地址自动匹配方法

Also Published As

Publication number Publication date
AU2884097A (en) 1998-01-05
EP0906547A1 (fr) 1999-04-07
CA2177941A1 (fr) 1997-12-01

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