JP3556109B2 - Air conditioner - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a reduction in operating power of an air conditioner, particularly to an air conditioner, and to effective use of surplus power at midnight.
[0002]
[Prior art]
This type of conventional air conditioner that stores and uses surplus electricity at midnight is mainly intended for business use or stores, and is disclosed in, for example, Japanese Patent Application Laid-Open No. 62-73031 (Japanese Patent Application No. 60-212400) or Japanese Patent Application Laid-Open No. 60-212400. This is disclosed in Japanese Unexamined Patent Publication No. Hei 6-54465 (Japanese Patent Application No. 4-205156).
[0003]
That is, after converting the nighttime power to a DC voltage required for the operation of the inverter of the electric compressor via a charger or a converter, the amount of electricity corresponding to the operation time and power consumption of the air conditioner is increased. A large-capacity storage battery is charged, and when the air conditioner is operated, this storage battery is switched and connected to the inverter section of the electric compressor so that the operation can be continued until the time corresponding to the discharge capacity of the storage battery. A configuration for switching to a commercial power supply and operating again is disclosed.
[0004]
As described above, in the conventional air conditioner, the storage battery is charged for effective use of the late-night power, and when using the stored power, the storage battery is switched to the inverter and used as a power source for the air conditioner. .
[0005]
[Problems to be solved by the invention]
However, in the configuration of the above-described conventional air conditioner, the operation can be performed for a long time only with the electric capacity of the storage battery, and all the large current at the time of starting or overload can be covered. For this reason, a large-capacity and large-sized storage battery is required. Similarly, the charger and the converter require large-capacity and expensive devices, so that the configuration is not suitable for general home air conditioners (room air conditioners).
[0006]
Further, when a lead storage battery is used as the storage battery, there is also a problem in practicality, such as the need for replacement maintenance of the storage battery in a short period of time because the cycle life of charge and discharge is short.
The present invention achieves low cost in such an air conditioner, further stores late-night surplus power in a room air conditioner for general households, and effectively uses the power, thereby reducing power consumption during the daytime. It is an object of the present invention to obtain an economic effect of an annual electricity bill by low-cost late-night power, together with a substantial energy saving effect.
[0007]
[Means for Solving the Problems]
The air conditioner of the present invention connects an outdoor heat exchanger, a capillary tube, and an indoor heat exchanger to an electric compressor to form a refrigeration cycle, and converts an outdoor blower, an indoor blower, and an AC power supply into DC. A variable-capacity air conditioner including a conversion unit that performs, and a variable voltage / variable frequency driving unit of the compressor,
A storage battery to be charged with midnight power, discharging means connected to the storage battery, and discharging when the predetermined time has elapsed after the air conditioner has started operating and the drive frequency of the compressor is equal to or higher than a predetermined frequency. Control means for driving the means for supplying power of the storage battery to the drive means of the compressor, and supplementing the operating power of the air conditioner supplied from the conversion means. is there.
[0008]
According to the present invention, low cost is realized, furthermore, surplus electric power is stored in a room air conditioner for general household use at night to effectively use the electric power, and substantial energy saving is achieved by reducing power consumption during the daytime. In addition to the effect, an air conditioner that can obtain the economic effect of the annual electricity bill by low-cost midnight power can be obtained. In addition, in the overload state at the time of starting, the discharge of the storage battery is avoided, so that the power can be stably supplemented for a long time.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
The invention according to claim 1 of the present invention provides a refrigerating cycle by connecting an outdoor heat exchanger, a capillary tube, and an indoor heat exchanger to a motor-driven compressor, thereby forming a refrigeration cycle. A variable-capacity air conditioner including a conversion unit that converts a power supply into DC, and a driving unit that controls a variable voltage and a variable frequency of the compressor,
A storage battery to be charged with midnight power, discharging means connected to the storage battery, and discharging when the predetermined time has elapsed after the air conditioner has started operating and the drive frequency of the compressor is equal to or higher than a predetermined frequency. Control means for driving the means for supplying power of the storage battery to the drive means of the compressor, and supplementing the operating power of the air conditioner supplied from the conversion means. Yes,
The supplementary operation of the operating power is performed by using the storage battery charged with the late-night power, and the operation is supplemented by the power supplementing method, whereby the continuous operation can be performed by the commercial power supply even when the storage battery has finished discharging. In addition, in the overload state at the time of starting, the discharge of the storage battery is avoided, and therefore, there is an effect that stable power supplement can be performed for a long time.
[0010]
In addition, the storage battery can be a small-capacity storage battery suitable for room air conditioners for general households because of the power supplement system, which can reduce the cost of the device, and can be applied to the air conditioner operating on commercial power supply via the discharging means. Power consumption can be reduced because small power is complemented.
[0011]
The invention according to claim 2 is the invention according to claim 1,
The discharge means of the storage battery is a constant power output or a constant current output, characterized in that the discharge power of the storage battery is configured to stably supply power to the drive means of the compressor,
This has the effect that stable power can be supplied to the driving means of the compressor in accordance with the storage capacity of the storage battery.
[0013]
The invention according to claim 3 is the invention according to claim 1, wherein the storage battery is a nickel-metal hydride storage battery or a lithium-ion storage battery.
Adopting a highly reliable storage battery with excellent charge / discharge cycle life has the effect of being maintenance-free for a long time and ensuring safety.
[0014]
Hereinafter, an air conditioner according to an embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 5, the refrigeration cycle of the air conditioner connects the outdoor heat exchanger 12, the capillary tube 13, and the indoor heat exchanger 14 to an electric compressor 6 having three-phase windings. Is formed. Since the operation of the refrigeration cycle and the air conditioner driven by the inverter is well known, the description thereof is omitted. In FIG. 5, 15 is an outdoor blower and 16 is an indoor blower.
[0015]
FIG. 1 is an overall configuration diagram of an air conditioner that executes an air conditioner operation method according to an embodiment of the present invention.
The AC power supply 1 is connected via the air conditioner indoor unit 2 to the input side of a converter (an example of a converting means for converting the AC power supply 1 into DC) 4 of the air conditioner outdoor unit 3, and the DC output of the converter 4 is connected to the compressor 6. It is connected to the input side of an inverter (an example of a variable voltage / variable frequency driving means of the compressor 6) 5 to be driven. The inverter 5 and the compressor 6 are provided inside the air conditioner outdoor unit 3.
[0016]
The control device (an example of a control unit) 7 of the air conditioner outdoor unit 3 receives an operation command from the air conditioner indoor unit 2 and controls the operation of the compressor 6 at a variable voltage and a variable frequency via the inverter 5.
[0017]
A charging converter 9 (an example of a charging unit) is connected to the power supply 8 in the late-night power time zone, and a storage battery 10 stored by the charging converter 9 is connected to the charging converter 9. The storage battery 10 is charged through the charging converter 9. The charging converter 9 monitors the terminal voltage of the storage battery 10 and has a function of determining whether or not it is in the midnight power time zone using a timer.
[0018]
The output of the storage battery 10 is connected to a constant power output (or a constant current output) discharging converter 11 (an example of discharging means). The discharging converter 11 is connected to the input side of the inverter 5 of the compressor 6. The power of the storage battery 10 is supplied to the inverter 5 of the compressor 6 via the discharge converter 11 so as to supplement the operating power of the air conditioner. The discharge converter 11 is connected to input a discharge permission signal (operation control signal) from the control device 7 of the outdoor unit 3. The discharge converter 11 is controlled by the outdoor control device 7 provided in the air conditioner outdoor unit 3. Driven. The discharge converter 11 monitors the battery voltage of the storage battery 10.
[0019]
The storage battery 10 uses a high-capacity type nickel-metal hydride storage battery (or a lithium ion storage battery) having an excellent long-term charge / discharge cycle life.
FIG. 4 shows an electric configuration diagram of the outdoor unit 3.
[0020]
The operation of the above configuration will be described with reference to the flowchart of FIG. 2 and the timing chart (region A) of FIG.
First, the operation of the charging converter 9 will be described.
[0021]
Charge converter 9 first determines whether or not it is in the midnight power time zone (for example, from 2:00 am to 4:00 am as shown in FIG. 3) (step-A1). It is determined whether or not the voltage of the storage battery 10 (storage battery voltage) is equal to or less than a predetermined value Vs (see FIG. 3) (discharge state) (step-A2). The charging voltage is applied to the storage battery 10 to perform charging at a constant current of about 1/3 of the rated current of the storage battery (step-A3). Then, it is determined that the storage battery 10 has reached the fully charged state by determining whether the storage battery voltage has risen above the predetermined value Vm (see FIG. 3) (step-A4). If the storage battery voltage rises above the predetermined value Vm, It is determined that the battery is fully charged, and the charging operation ends (step-A5). When the storage battery 10 reaches a fully charged state, its terminal voltage and storage battery temperature generally increase.
[0022]
By the operation of the charging capacitor 9, the surplus power at midnight is charged to the storage battery 10 in the midnight power time zone.
Next, the operation of the control device 7 of the outdoor unit 3 will be described.
[0023]
When an operation command output from the indoor unit 2 is input when the cooling operation of the room air conditioner is specified (step-B1), the control device 7 controls the inverter 5 to drive the compressor 6 to start the cooling operation. (Step-B2). At the start of the operation, the compressor 6 is operated at the maximum rotation speed and the maximum cooling capacity, the room is rapidly cooled to lower the room temperature to near the set temperature, and then the operating frequency of the compressor 6 is reduced to reduce the room temperature. It shifts to capacity operation and performs stable operation.
[0024]
When a predetermined time Ts (see FIG. 3) has elapsed from the start of the operation of the air conditioner (step-B3), it is determined whether the drive frequency of the compressor 6 is equal to or higher than the predetermined frequency Ls (step-B4). If the drive frequency is determined to be equal to or higher than the predetermined frequency Ls, a discharge permission signal (operation control signal) is output to the discharge converter 11 (step-B5).
[0025]
Then, when an operation stop command output from the indoor unit 2 is input by designating the stop of the cooling operation of the room air conditioner (step-B6), the power supply from the inverter 5 is stopped, the compressor 6 is stopped, and the cooling operation is performed. (Step-B7).
[0026]
By the operation of the control device 7 of the air conditioner outdoor unit 3, the inverter 5 is driven to perform the cooling operation, the predetermined time Ts has elapsed from the start of the operation of the air conditioner, and the drive frequency of the compressor 6 is equal to or higher than the predetermined frequency Ls. , A discharge permission signal is output to the discharge converter 11.
[0027]
Next, the operation of the discharge converter 11 will be described.
When the discharge converter 11 receives a discharge permission signal from the control device 7 of the outdoor unit 3 (step-C1), it supplies constant power from the storage battery 10 to the input of the inverter 5 of the outdoor unit 3 as shown in FIG. (Step-C2).
[0028]
This operation complements the operating power of the air conditioner, thereby reducing the power consumption of the air conditioner. When the outside air temperature is high and the cooling load is large, the storage battery 10 continuously discharges at a predetermined constant power.
[0029]
Then, the storage battery voltage is monitored, and it is determined that the remaining capacity of the storage battery 10 has decreased to a predetermined value or less due to the storage battery voltage dropping rapidly and falling below a predetermined value Vs (see FIG. 3) (discharge state). Upon detection (Step-C3), the discharging operation is terminated (Step-C4). When the remaining capacity of the storage battery 10 decreases below a predetermined value due to discharge, the storage battery voltage generally rapidly decreases.
[0030]
By the operation of the discharge converter 11, constant power is supplied to the inverter 5 according to the discharge permission signal instructed by the control device 7, and power is complemented.
As described above, the surplus power at midnight is stored in the storage battery 10, and during the daytime, the control device 7 drives the discharge converter 11 to the inverter 5 operating on the commercial power supply to supplement the low power of the storage battery 10. Thus, it is possible to obtain a substantial energy saving effect by reducing power consumption, and to obtain an economic effect of an annual electricity bill by low-cost late-night power.
[0031]
In addition, the storage battery 10 can be reduced in capacity and cost can be reduced because of the power supplementing method, so that the present invention can be applied to room air conditioners for general households. In addition, even if the storage battery 10 finishes discharging due to the power supplementing method, the operation is continued with the commercial power supply, so that comfort can be maintained.
[0032]
Further, since the output of the discharge converter 11 is of a constant power type, stable power can be supplied to the air conditioner according to the storage capacity of the storage battery 10. Further, when the air conditioner is started (when large power is consumed) by the control device 7, Discharge is started, the discharge is started when a predetermined time Ts has elapsed from the start of the operation of the air conditioner and the drive frequency of the compressor 6 has become equal to or higher than the predetermined frequency Ls, and power is supplemented during stable operation. Time stable power supplementation is possible.
[0033]
In addition, since the storage battery 10 is configured to use a highly reliable nickel-metal hydride storage battery or lithium-ion storage battery, it has many advantages such as long-term maintenance-free operation and safety.
[0034]
In the present embodiment, the small power of the storage battery 10 is supplemented to the commercial power supply. However, as shown in the area B of the timing chart of FIG. The power can be supplemented from the storage battery 10 even in the low-capacity driving at night following the driving. Thus, when the cooling load is small, the power can be complemented within the output capacity of the discharge converter 11. Then, the discharge converter 11 detects that the remaining capacity of the storage battery 10 has reached the lower limit value and the battery voltage has dropped, and stops the discharging operation.
[0035]
【The invention's effect】
As described above, according to the present invention, the surplus electric power at midnight is stored in the storage battery, and the control unit drives the discharging unit to the driving unit of the compressor operating on the commercial power supply to supplement the small power of the storage battery. Thus, it is possible to obtain a substantial energy saving effect by reducing power consumption, and to obtain an economic effect of an annual electricity bill by low-cost late-night power. In addition, when a predetermined time has elapsed from the start of the operation of the air conditioner and the driving frequency of the compressor has become equal to or higher than the predetermined frequency, the discharge is started, and the power is complemented during the stable operation, so that the power can be stabilized for a long time. It becomes possible.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram of an air conditioner according to an embodiment of the present invention.
FIG. 2 is an operation flowchart of the air conditioner.
FIG. 3 is a timing chart of the air conditioner.
FIG. 4 is an electric configuration diagram of an outdoor unit of the air conditioner.
FIG. 5 is a refrigeration cycle diagram of the air conditioner.
[Explanation of symbols]
1 Commercial power supply 2 Indoor unit of air conditioner 3 Outdoor unit of air conditioner 4 Converter (conversion means)
5 Inverter (drive means)
6 Compressor 7 Outdoor control device (control means)
8 Midnight power supply 9 Charging converter (charging means)
10 Storage battery 11 Discharge converter (discharge means)

Claims (3)

An electric compressor, an outdoor heat exchanger, a capillary tube, and an indoor heat exchanger connected by piping to form a refrigeration cycle, an outdoor blower, an indoor blower, a conversion unit for converting an AC power supply to DC, and the compressor. A variable capacity air conditioner comprising a variable voltage and a variable frequency driving means,
A storage battery charged with midnight power,
Discharging means connected to the storage battery;
When a predetermined time has elapsed after the air conditioner has started operating and the drive frequency of the compressor is equal to or higher than a predetermined frequency, the air conditioner drives the discharge means to supply power of the storage battery to the drive means of the compressor. Control means for supplementing the operating power of the air conditioner supplied from the conversion means. 2. The air conditioner according to claim 1, wherein the discharging unit of the storage battery is configured to output a constant power or a constant current, and stably supply the discharging power of the storage battery to the driving unit of the compressor. 3. The air conditioner according to claim 1 , wherein the storage battery is a nickel hydrogen storage battery or a lithium ion storage battery .

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