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
  • F24F11/70—Control systems characterised by their outputs; Constructional details thereof
  • F24F11/80—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air
  • F24F11/83—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air by controlling the supply of heat-exchange fluids to heat-exchangers
• • 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
  • F24F11/88—Electrical aspects, e.g. circuits
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
  • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
  • F25B49/00—Arrangement or mounting of control or safety devices
  • F25B49/02—Arrangement or mounting of control or safety devices for compression type machines, plants or systems
  • F25B49/025—Motor control arrangements
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
  • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
  • F25B13/00—Compression machines, plants or systems, with reversible cycle
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
  • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
  • F25B2313/00—Compression machines, plants or systems with reversible cycle not otherwise provided for
  • F25B2313/007—Compression machines, plants or systems with reversible cycle not otherwise provided for three pipes connecting the outdoor side to the indoor side with multiple indoor units
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
  • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
  • F25B2313/00—Compression machines, plants or systems with reversible cycle not otherwise provided for
  • F25B2313/023—Compression machines, plants or systems with reversible cycle not otherwise provided for using multiple indoor units
  • F25B2313/0231—Compression machines, plants or systems with reversible cycle not otherwise provided for using multiple indoor units with simultaneous cooling and heating
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
  • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
  • F25B2313/00—Compression machines, plants or systems with reversible cycle not otherwise provided for
  • F25B2313/025—Compression machines, plants or systems with reversible cycle not otherwise provided for using multiple outdoor units
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
  • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
  • F25B2600/00—Control issues
  • F25B2600/02—Compressor control
  • F25B2600/021—Inverters therefor
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
  • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
  • F25B2600/00—Control issues
  • F25B2600/02—Compressor control
  • F25B2600/024—Compressor control by controlling the electric parameters, e.g. current or voltage
• • 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

• the present disclosure relates to an air conditioner, and more particularly, to an air conditioner including a plurality of outdoor units and a plurality of indoor units.
• An air conditioner is used to keep an indoor area at a comfortable state by cooling or heating indoor air using a refrigerant heat exchanging cycle.
• the air conditioner includes an indoor unit and an outdoor unit.
• the outdoor unit includes a compressor motor for driving a compressor and an outdoor fan motor for rotating an outdoor fan.
• the indoor unit includes an indoor fan motor for rotating an indoor fan.
• Induction motors or brushless direct current motors (BLDCs) can be used as the compressor motor, the indoor fan motor, and the outdoor motor.
• Air conditioners of the related art have the following disadvantages.
• an induction motor can be easily fabricated with low costs, the initial operational efficiency of the induction motor is low due to slipping between a rotor and a stator caused by a difference between a mechanical speed and an electrical speed. Moreover, since the speed of the induction motor is controlled by varying a voltage applied to the induction motor, the amount of heat generation of the induction motor is proportional to the capacity of the induction motor. Therefore, a large-capacity induction motor has poor efficiency and reliability. In addition, it is difficult to precisely control the induction motor, and the induction motor generates much noise due to the slipping between the rotor and stator of the induction motor and wearing caused by the slipping. Furthermore, the induction motor is only suitable to constant speed operations. Therefore, the induction motor is not suitable for a variable speed fan motor or an inverter compressor of an air conditioner.
• a BLDC motor includes a rotor having magnets, a stator around which a coil is wound, a hole sensor configured to detect the position of the rotor, a control device configured to control the rotation of the rotor according to the position of the rotor detected by the hole sensor, and a drive.
• the speed and torque of the BLDC motor is controlled by intermittently supply a current (phase angle variation) to the BLDC motor according to the position of the rotor detected by the hole sensor. Since a current supplied to the coil of the stator is controlled using a semiconductor device, the BLDC motor has low electric and mechanical noises.
• Embodiments provide an air conditioner in which motors are efficiently operated.
• Embodiments also provide an air conditioner designed to effectively protect components.
• Embodiments also provide an air conditioner that can be operated with low costs.
• Embodiments also provide an air conditioner that can be fabricated with low costs.
• Embodiments also provide a reliable air conditioner.
• an air conditioner including: an outdoor unit including a compressor, a compressor motor, an outdoor heat exchanger, and an outdoor fan motor; an indoor unit connected to the outdoor unit, the indoor unit including an indoor heat exchanger and an indoor fan motor; a converter converting input AC power into DC power; an inverter converting the DC power received from the converter into three-phase power, the inverter supplying the three-phase power to at least one of the compressor motor, the outdoor fan motor, and the indoor fan motor; a position detector comparing a back electromotive force of the at least one motor with a reference signal so as to output a square wave signal; and a controller outputting a pulse width modulation (PWM) control signal to the inverter based on the square wave signal received from the position detector so as to control a speed of a rotor of the at least one motor.
• PWM pulse width modulation
• an air conditioner including: a plurality of outdoor units each including a compressor, a compressor motor, an outdoor heat exchanger, and an outdoor fan motor; a plurality of indoor units each including an indoor heat exchanger and an indoor fan motor, each of the indoor units operating in at least one of a cooling mode, a heating mode, and a stop mode; a high-pressure pipe configured to supply a portion of a refrigerant discharged from the compressor and passing through the outdoor heat exchanger to the indoor heat exchanger of the indoor unit that operates in the cooling mode; a liquid pipe configured to supply the other portion of the refrigerant discharged from the compressor to the indoor heat exchanger of the indoor unit that operates in the heating mode; a low-pressure pipe configured to supply the refrigerant discharged from the indoor heat exchanger of the indoor unit that operates in the cooling mode or the heating mode to the compressors of the outdoor units; a distributor configured to supply the refrigerant from the high-pressure pipe and the liquid pipe to the indoor heat exchanger of the indoor unit that operates in
• an air conditioner including: a plurality of outdoor units each including a compressor, a compressor motor, an outdoor heat exchanger, an outdoor fan motor, and a control part; and a plurality of indoor units connected to the outdoor units and operating in at least one of a cooling mode, a heating mode, and a stop mode, each of the indoor unit including an indoor heat exchanger, an indoor fan motor, and a control part, wherein each of the control parts of the indoor and outdoor units detects positions of rotors of the compressor motor and the outdoor fan motor or the indoor fan motor so as to control speeds and initial positions of the compressor motor and the outdoor fan motor by PWM.
• FIG. 1 is a block diagram illustrating a switching-operational air conditioner according to an embodiment.
• FIG. 2 is a block diagram illustrating a multi-operational air conditioner according to an embodiment.
• Fig. 3 is a circuit diagram illustrating power factor correction (PFC) circuits of control parts of an air conditioner according to an embodiment. Best Mode for Carrying Out the Invention
• FIG. 1 is a block diagram illustrating a switching-operational air conditioner according to an embodiment.
• the operation of the switch-operational air conditioner can be switched between cooling mode and heating mode.
• the switch-operational air conditioner includes a plurality of outdoor units
• First and second refrigerant pipes 311 and 312 are connected to the outdoor units 110 and 120.
• the first and second refrigerant pipes 311 and 312 are connected to the distributor 310, and the distributor 310 is connected to the indoor units 210, 220, and 230 through a plurality of branch pipes.
• Each of the outdoor units 110 and 120, and the indoor units 210, 220, and 230 includes a control part. The control part will be described later in detail.
• the distributor 310 distributes the refrigerant to the indoor units 210, 220, and 230 through the branch pipes. Then, the refrigerant is evaporated in the indoor units 210, 220, and 230, and thus an indoor area can be cooled. Thereafter, the refrigerant flows back to the distributor 310 where the refrigerant is guide to the outdoor units 110 and 120 through the second refrigerant pipe 312.
• the distributor 310 distributes the refrigerant to the indoor units 210, 220, and 230. Then, the refrigerant is condensed in the indoor units 210, 220, and 230, and thus, the indoor area can be heated. Thereafter, the refrigerant flows back to the distributor 310 from the indoor units 210, 220, and 230. Then, the distributor 310 guides the refrigerant to the outdoor units 110 and 120 through the first refrigerant pipe 311.
• some of the indoor units 210, 220, and 230 can be in stop mode.
• FIG. 2 is a block diagram illustrating a multi-operational air conditioner according to an embodiment.
• like reference numerals denotes like elements.
• the multi-operational air conditioner of the current embodiment can operate both in cooling mode and heating mode.
• the multi-operational air conditioner includes a plurality of outdoor units
• the multi-operational air conditioner includes a plurality of outdoor units. However, the multi-operational air conditioner can include only one outdoor unit.
• the distributor 310 distributes the refrigerant to the indoor units 210, 220, and 230 through the branch pipes. Then, the refrigerant is evaporated in the indoor units 210, 220, and 230, and thus an indoor area can be cooled. Thereafter, the refrigerant flows back to the distributor 310 where the refrigerant is guide to the outdoor units 110 and 120 through the second refrigerant pipe 312.
• the other portion of the refrigerant discharged from the outdoor units 110 and 120 is guided to the liquid pipe 316. Then, the refrigerant flows from the liquid pipe 316 to the distributor 310.
• the distributor 310 guides the refrigerant to the others of the indoor units 210, 220, and 230 that operate as condensers for heating indoor areas. For example, the distributor 310 can guide the refrigerant to the indoor units 220 and 230. Thereafter, the refrigerant is discharged from the indoor units 220 and 230 to the distributor 310 where a portion of the refrigerant is guided to the indoor unit 210 that operates as an evaporator and the other portion of the refrigerant is guided to the low- pressure pipe 317. The refrigerant discharged from the indoor units 210, 220, and 230 to the low-pressure pipe 317 is guided to the outdoor units 110 and 120.
• Fig. 3 is a circuit diagram illustrating power factor correction (PFC) circuits of control parts of an air conditioner according to an embodiment.
• the switching-operational air conditioner illustrated in Fig. 1 and the multi-operational air conditioner illustrated in Fig. 2 have substantially the same control parts.
• the following description of the control parts can be applied to both the switching-operational air conditioner and the multi-operational air conditioner.
• the air conditioner includes a plurality of outdoor units
• the outdoor units 110 and 120 includes a main outdoor unit 110 and a sub outdoor unit 120.
• Control parts of the main outdoor unit 110, the sub outdoor unit 120, and the indoor units 210, 220, and 230 are configured with power factor correction (PFC) circuits.
• a PFC circuit includes an additional power-saving circuit for improving power efficiency and is designed for stably supplying a current, preventing conversion of a current into heat, and reducing electromagnetic waves. The control parts will now be described in detail.
• the main outdoor unit 110 includes a converter 111 for receiving power.
• the converter 111 is connected to a positive DC power source and a negative DC source.
• the negative DC source connected to the converter 111 is grounded.
• the main outdoor unit 110 further includes a main controller 112.
• the main controller 112 is connected to two inverters 113 and 116.
• the main controller 112 of the main outdoor unit 110 includes two ports PWM Port 1 and PWM Port 2 connected to the inverters 113 and 116.
• One of the inverters 113 and 116 (e.g., the inverter 113) is connected to a compressor motor 114 of the main outdoor unit 110 through three phase terminals (u, v, and w phase terminals).
• a DC inverter motor can be used as the compressor motor 114 of the main outdoor unit 110.
• a rotor position detector 115 is connected to the v and w phase terminals between the inverter 113 and the compressor motor 114 for detecting the position of a rotor of the compressor motor 114.
• the rotor position detector 115 of the main outdoor unit 110 is connected to position detection ports Sl and S2 of the main controller 112.
• the rotor position detector 115 When the rotor position detector 115 detects that the back electromotive force of the compressor motor 114 is greater than a reference value, the rotor position detector 115 outputs an on-state signal to the main controller 112. When the rotor position detector 115 detects that the back electromotive force of the compressor motor 114 is smaller than the reference value, the rotor position detector 115 outputs an off-state signal to the main controller 112.
• One of the inverters 113 and 116 (e.g., the inverter 116) is connected to an outdoor fan motor 117 of the main outdoor unit 110 through three phase terminals (u, v, and w phase terminals).
• a DC inverter motor can be used as the outdoor fan motor 117.
• a rotor position detector 118 is connected to the v and w phase terminals between the inverter 116 and the outdoor fan motor 117 for detecting the position of a rotor of the outdoor fan motor 117.
• the rotor position detector 118 of the main outdoor unit 110 is connected to position detection ports S3 and S4 of the main controller 112.
• the rotor position detector 118 When the rotor position detector 118 detects that the back electromotive force of the outdoor fan motor 117 is greater than a reference value, the rotor position detector 118 outputs an on-state signal to the main controller 112. When the rotor position detector 118 detects that the back electromotive force of the outdoor fan motor 117 is smaller than the reference value, the rotor position detector 118 outputs an off- state signal to the main controller 112.
• the sub outdoor unit 120 includes a converter 121 for receiving power.
• the converter 121 is connected to a positive DC power source and a negative DC source.
• the negative DC source connected to the converter 121 is grounded.
• the sub outdoor unit 120 further includes a sub controller 122.
• the sub controller 122 controls the sub controller
• the sub controller 122 of the sub outdoor unit 120 includes two ports PWM Port 1 and PWM Port 2 connected to the inverters 123 and 126.
• One of the inverters 123 and 126 (e.g., the inverter 123) is connected to a compressor motor 124 of the sub outdoor unit 120 through three phase terminals (u, v, and w phase terminals).
• a DC inverter motor can be used as the compressor motor 124 of the sub outdoor unit 120.
• a rotor position detector 125 is connected to the v and w phase terminals between the inverter 123 and the compressor motor 124 for detecting the position of a rotor of the compressor motor 124.
• the rotor position detector 125 of the sub outdoor unit 120 is connected to position detection ports Sl and S2 of the sub controller 122.
• the rotor position detector 125 When the rotor position detector 125 detects that the back electromotive force of the compressor motor 124 is greater than a reference value, the rotor position detector 125 outputs an on-state signal to the sub controller 122. When the rotor position detector 125 detects that the back electromotive force of the compressor motor 124 is smaller than the reference value, the rotor position detector 125 outputs an off-state signal to the sub controller 122.
• One of the inverters 123 and 126 (e.g., the inverter 126) is connected to an outdoor fan motor 127 of the sub outdoor unit 120 through three phase terminals (u, v, and w phase terminals).
• a DC inverter motor can be used as the outdoor fan motor 127.
• a rotor position detector 128 is connected to the v and w phase terminals between the inverter 126 and the outdoor fan motor 127 for detecting the position of a rotor of the outdoor fan motor 127.
• the rotor position detector 128 of the sub outdoor unit 120 is connected to position detection ports S3 and S4 of the sub controller 122.
• the rotor position detector 128 When the rotor position detector 128 detects that the back electromotive force of the outdoor fan motor 127 is greater than a reference value, the rotor position detector 128 outputs an on-state signal to the sub controller 122. When the rotor position detector 128 detects that the back electromotive force of the outdoor fan motor 127 is smaller than the reference value, the rotor position detector 128 outputs an off-state signal to the sub controller 122.
• the main controller 112 of the main outdoor unit 110 is electrically connected with the sub controller 122 of the sub outdoor unit 120 for exchanging electric signals.
• the main controller 112 of the main outdoor unit 110 can output a control signal to the sub controller 122 of the sub outdoor unit 120.
• the sub controller 122 of the sub outdoor unit 120 can control the sub outdoor unit 120 according to the control signal received from the main controller 112 of the main outdoor unit 110.
• the inverters 113 and 123 of the main outdoor unit 110 and the sub outdoor unit 120 are used to convert the DC power into three-phase AC power.
• the inverters 113 and 123 are switching-controlled by the main controller 112 of the main outdoor unit 110 and the sub controller 122 of the sub outdoor unit 120, respectively. Therefore, the three-phase AC power can be supplied from the inverters 113 and 123 to the outdoor fan motors 117 and 127, respectively.
• the indoor units 210, 220, and 230 include converters 211, 221, and 231, respectively.
• the converters 211, 221, and 231 are connected to positive and negative DC power sources.
• the negative DC source connected to the converters 211, 221, and 231 is grounded.
• the indoor units 210, 220, and 230 further include controllers 212, 222, and 232, re- spectively.
• the controllers 212, 222, and 232 are connected to the main controller 112 of the main outdoor unit 110 for exchanging electric signals.
• the controllers 212, 222, and 232 of the indoor units 210, 220, and 230 are connected to inverters 213, 223, and 233, respectively.
• the controllers 212, 222, and 232 of the indoor units 210, 220, and 230 include ports PWM Port connected to the inverters 213, 223, and 233, respectively.
• the inverters 213, 223, and 233 are connected to indoor fan motors 214, 224, and
• DC inverter motors can be used as the indoor fan motors 214, 224, and 234.
• Rotor position detectors 215, 225, and 235 are connected to the v and w phase terminals between the inverters 213, 223, and 233 and the indoor fan motors 214, 224, and 234 for detecting the positions of rotors of the indoor fan motors 214, 224, and 234.
• the rotor position detectors 215, 225, and 235 are respectively connected to the inverters 213, 223, and 233 through position detection ports Tl and T2 of the controllers 212, 222, and 232.
• the rotor position detector 215 When the rotor position detector 215 detects that the back electromotive force of the indoor fan motor 214 is greater than a reference value, the rotor position detector 215 outputs an on-state signal to the controller 212. When the rotor position detector 215 detects that the back electromotive force of the indoor fan motor 214 is smaller than the reference value, the rotor position detector 215 outputs an off-state signal to the controller 212.
• the rotor position detectors 225 and 235 output on-state and off-state signals to the controllers 222 and 232 in the same manner as the rotor position detector 215.
• the converters 211, 221, and 231 of the indoor units 210, 220, and 230 are used to convert input AC power into DC power and supply the DC power to the inverters 213, 223, and 233.
• the inverters 213, 223, and 233 convert the DC power into three-phase AC power.
• the inverters 213, 223, and 233 are switching-controlled by the controllers 212, 222, and 232. Therefore, the three-phase AC power can be supplied from the inverters 213, 223, and 233 to the indoor fan motors 214, 224, and 234, respectively.
• the indoor fan motors 214, 224, and 234 can be controlled.
• the operation control signal is transmitted from the controllers 212, 222, and 232 of the indoor units 210, 220, and 230 to the main controller 112 of the main outdoor unit 110.
• the main controller 112 evaluates the operation control signal. Then, the main controller 112 controls the main outdoor unit 110 and the sub outdoor unit 120 according to the operation control signal as follows.
• the converter 111 of the main outdoor unit 110 converts input AC power into DC power.
• the inverters 113 and 116 of the main outdoor unit 110 receives the DC power from the converter 111 and converts the DC power into three-phase AC power. Then, the inverters 113 and 116 supply the three-phase AC power to the compressor motor 114 and the outdoor fan motor 117, respectively. Therefore, the compressor motor 114 and the outdoor fan motor 117 can be operated.
• the rotor position detector 115 detects the back electromotive force voltage of the compressor motor 114 through the v and w phase terminals
• the rotor position detector 118 detects the back electromotive force voltage of the outdoor fan motor 117 through the v and w phase terminals.
• the rotor position detector 115 determines that the back electromotive force voltage of the compressor motor 114 detected through the v or w phase terminal is greater than a reference value, the rotor position detector 115 outputs an on-state signal to the main controller 112, and when the rotor position detector 115 determines that the back electromotive force voltage of the compressor motor 114 detected through the v or w phase terminal is smaller than the reference value, the rotor position detector 115 outputs an off- state signal to the main controller 112.
• the rotor position detector 118 determines that the back electromotive force voltage of the outdoor fan motor 117 detected through the v or w phase terminal is greater than a reference value, the rotor position detector 118 outputs an on- state signal to the main controller 112, and when the rotor position detector 118 determines that the back electromotive force voltage of the outdoor fan motor 117 detected through the v or w phase terminal is smaller than the reference value, the rotor position detector 118 outputs an off-state signal to the main controller 112.
• the rotor position detector 115 when the rotor position detector 115 determines that back electromotive force voltages detected through the v and w phase terminals are smaller than a reference value, the rotor position detector 115 can generate off-state signals for the v and w phases and output the off-state signals to the main controller 112 of the main outdoor unit 110.
• the rotor position detector 118 can operate in the same way as the rotor position detector 115. In this case, the main controller 112 determines that the rotor of the compressor motor 114 or the outdoor fan motor 117 is in u phase.
• the rotor position detector 115 or 118 may output an off-state signal for the v phase and an on-state signal for the w phase and output them to the main controller 112. In this case, the main controller 112 may determine that the compressor motor 114 or the outdoor fan motor 117 is in w phase.
• the main controller 112 can control the inverter 113 by pulse width modulation (PWM) so as to place the rotor of the compressor motor 114 or the outdoor fan motor 117 at a predetermined position such as u, v, and w phase positions.
• PWM pulse width modulation
• the PWM means modulation of the width of constant- voltage current pulses for controlling the average current of the current pulses.
• the PWM is performed by controlling the on/off ratio of a switch to supply 100% of electricity to a motor instantaneously. Since the switch is rapidly changed between on and off states in the PWM, the mechanical response of the motor may be slower than the on/off operation of the switch. Thus, the motor may have output power corresponding to the average value of a current supplied to the motor while the switch is in on state. That is, since the operation of the motor can be controlled by the electrical on/off operation of the switch, it is not necessary to dispose an additional variable resistor between the motor and a power source. Therefore, a current can be supplied to the motor substantially without thermal loss, and the power consumption of the motor can be significantly reduced.
• DC voltages to the compressor motors 114 and 124 are on/off controlled by the PWM, generation of a high-frequency current can be prevented, and thus compressors can be protected. Moreover, since the speeds of the compressor motors 114 and 124 can be precisely controlled, the compressor motors 114 and 124 can be used in inverter compressors. Furthermore, since DC voltages to the compressor motors 114 and 124 are on/off controlled by the PWM, the efficiency or reliability of the compressor motors 114 and 124 is less affected by heat generated in proportional to the capacity of the compressor motors 114 and 124.
• the positions of the rotors of the compressor motors 114 and 124 can be precisely detected using the rotor position detectors 115 and 125, an additional position sensor is not necessary. Moreover, the positions of the compressor motors 114 and 124 can be detected at all three phase positions (u, v, and w phase positions), damages of compressors can be prevented even when drives of the compressor motors 114 and 124 are out of order.
• the main controller 112 of the main outdoor unit 110 sends control signals to the sub controller 122 of the sub outdoor unit 120 for controlling the compressor motor 124 and the outdoor fan motor 127, and the sub controller 122 of the sub outdoor unit 120 controls the initial positions of the rotors of the compressor motor 124 and the outdoor fan motor 127 in the same way as the main controller 112 of the main outdoor unit 110.
• a predetermined amount of refrigerant is supplied to the indoor units 210, 220, and 230 under the control of the main controller 112 according to a temperature of an indoor area selected by an operation control signal input through the indoor units 210, 220, and 230.
• the main controller 112 sends control signals to the controllers 212, 222, and 232 of the indoor units 210, 220, and 230 so as to operate the indoor fan motors 214, 224, and 234 at predetermined speeds according to cooling or heating load determined by the operation control signal.
• the converters 211, 221, and 231 of the indoor units 210, 220, and 230 convent input AC power into DC power.
• the inverters 213, 223, and 233 of the lower extension 230 convert the DC power into three-phase AC power.
• the inverters 213, 223, and 233 supply the three-phase AC power to the indoor fan motors 214, 224, and 234. In this way, the indoor fan motors 214, 224, and 234 are operated.
• the controllers 212, 222, and 232 of the indoor units 210, 220, and 230 control the initial positions of the rotors of the indoor fan motors 214, 224, and 234 in the same way as the main controller 112 and the sub controller 122.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Physics & Mathematics (AREA)
• Thermal Sciences (AREA)
• Air Conditioning Control Device (AREA)
• Control Of Motors That Do Not Use Commutators (AREA)

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Citations (4)

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• 2007
  • 2007-03-13 KR KR1020070024578A patent/KR20080083846A/ko not_active Application Discontinuation
• 2008
  • 2008-03-11 WO PCT/KR2008/001373 patent/WO2008111788A1/en active Application Filing
  • 2008-03-11 EP EP08723410A patent/EP2122264A4/de not_active Withdrawn

Patent Citations (4)

Non-Patent Citations (1)

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