KR20240006212A - air conditioner - Google Patents

Abstract

An air conditioner according to an embodiment of the present invention includes a connection part connected to an outlet supplied with alternating current power through a power plug; a first voltage sensor that detects an input voltage input through the connection unit; a second voltage sensor connected to the outlet with a signal line to detect the supply voltage of the outlet; and a control unit that stops operation of the air conditioner when the input voltage state detected by the first voltage sensor is different from the supply voltage state sensed by the second voltage sensor.

Description

air conditioner

The present invention relates to an air conditioner, and to an air conditioner that detects arcs and prevents accidents.

Air conditioners are installed to provide a more comfortable indoor environment for humans by discharging hot and cold air into the room, controlling the indoor temperature, and purifying the indoor air to create a comfortable indoor environment. Generally, an air conditioner includes an indoor unit composed of a heat exchanger and installed indoors, and an outdoor unit composed of a compressor and a heat exchanger that supplies refrigerant to the indoor unit.

To supply electricity to home appliances, use outlets, power strips, etc., and extend the wire when necessary to supply electricity. Home appliance power lines can be damaged for a variety of reasons. For example, even if a 45A current flows for just 100ms, there is a possibility that a fire may occur.

In particular, in the case of air conditioners, due to the nature of the product, wires are extended to connect indoor and outdoor units, and contact points occur during the connection process. If these contacts are connected normally, there is no problem, but contact failure may occur due to aging, burnout, etc., and if the contacts come apart in the process, there is a risk of sparks (arcs) occurring.

Arc generation generates copper oxide and cuprous oxide through contact with oxygen, and the generation of Joule heat is accelerated, which can cause a fire due to a series arc, and a fire can occur due to a parallel arc due to coating deterioration, etc. Therefore, in the United States and other countries, the use of AFCI (Arc Fault Circuit Interrupt) circuit breakers is essential to prevent fires by blocking the current when an arc occurs.

Prior literature (Korean Patent Publication No. 10-2010-0045901) discloses an AFCI circuit breaker. These AFCI breakers do not reflect product-specific characteristics such as operating current, voltage, and environment, so arc detection accuracy in the section where the product is operating may be low or may not be detected quickly.

The purpose of the present invention is to provide an air conditioner that can accurately detect the presence of arcs and the location of abnormalities at the product end.

The purpose of the present invention is to provide an air conditioner that can quickly detect whether an arc exists at the product end.

The purpose of the present invention is to provide an air conditioner that can quickly respond to arcs and prevent fires.

An air conditioner according to an embodiment of the present invention for achieving the above object includes a connection part connected to an outlet supplied with alternating current power through a power plug; a first voltage sensor that detects an input voltage input through the connection unit; a second voltage sensor connected to the outlet with a signal line to detect the supply voltage of the outlet; and a control unit that stops operation of the air conditioner when the input voltage state detected by the first voltage sensor is different from the supply voltage state sensed by the second voltage sensor.

The control unit may stop the compressor if the input voltage state and the supply voltage state are different.

The control unit may determine an arc when the input voltage state and the supply voltage state are different and the input voltage state corresponds to a distorted waveform.

If the input voltage state is different from the supply voltage state and the supply voltage state corresponds to a distorted waveform, the control unit may determine that the signal line is abnormal.

The control unit may control the operation state to be maintained when the input voltage state and the supply voltage state are the same.

If the input voltage state and the supply voltage state are the same, the control unit may control the operation state to be maintained even if the input voltage state and the supply voltage state correspond to a distorted waveform.

The air conditioner according to an embodiment of the present invention may further include a rectifier connected to the connection unit and rectifying the AC power input through the connection unit; and a DC terminal capacitor connected to the output terminal of the rectifier unit.

The air conditioner according to an embodiment of the present invention may further include an output unit that outputs an operating state and a warning according to a control command from the control unit.

According to at least one of the embodiments of the present invention, it is possible to accurately detect whether an arc exists and where an abnormality occurs at the product end.

Additionally, according to at least one of the embodiments of the present invention, the presence of an arc can be quickly detected at the product end.

Additionally, according to at least one of the embodiments of the present invention, it is possible to quickly respond to an arc and prevent a fire.

Meanwhile, various other effects will be disclosed directly or implicitly in the detailed description according to embodiments of the present invention to be described later.

1 is a diagram illustrating the configuration of an air conditioner according to an embodiment of the present invention.
Figure 2 is a diagram illustrating a power connection between an indoor unit and an outdoor unit.
Figure 3 is a diagram briefly illustrating a configuration for arc detection according to an embodiment of the present invention.
Figure 4 is a diagram briefly illustrating an arc detection circuit according to an embodiment of the present invention.
5 to 8 are diagrams referenced in the description of arc detection according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. However, it goes without saying that the present invention is not limited to these embodiments and can be modified into various forms.

In the drawings, parts not related to the description are omitted in order to clearly and briefly explain the present invention, and identical or extremely similar parts are denoted by the same drawing reference numerals throughout the specification.

Meanwhile, the suffixes “module” and “part” for components used in the following description are simply given in consideration of the ease of writing this specification, and do not give any particularly important meaning or role in and of themselves. Accordingly, the terms “module” and “unit” may be used interchangeably.

1 is a diagram illustrating the configuration of an air conditioner according to an embodiment of the present invention.

Referring to FIG. 1, the air conditioner 100 according to the present invention may include an indoor unit 20 and an outdoor unit 30 connected to the indoor unit 20.

The indoor unit 20 of the air conditioner can be any of a stand-type air conditioner, a wall-mounted air conditioner, and a ceiling-type air conditioner, but the drawing shows the stand-type indoor unit 20 as an example.

Meanwhile, the air conditioner 100 may further include at least one of a ventilator, an air purifier, a humidifier, and a heater, and may operate in conjunction with the operations of the indoor unit and outdoor unit.

The outdoor unit 30 includes a compressor (not shown) that receives and compresses refrigerant, an outdoor heat exchanger (not shown) that exchanges heat between the refrigerant and outdoor air, and an accumulator (not shown) that extracts gaseous refrigerant from the supplied refrigerant and supplies it to the compressor. and a four-way valve (not shown) that selects the refrigerant flow path according to heating operation. In addition, it further includes a number of sensors, valves, and an oil recovery device, but a description of their configuration will be omitted below.

The outdoor unit 30 operates the provided compressor and outdoor heat exchanger to compress or heat exchange the refrigerant according to settings and supply the refrigerant to the indoor unit 20. The outdoor unit 30 may be driven by a remote controller (not shown) or by a demand from the indoor unit 20. At this time, as the cooling/heating capacity varies in response to the indoor unit being driven, the operating number of outdoor units and the operating number of compressors installed in the outdoor unit can also be varied. In addition, although FIG. 1 shows one indoor unit 20 and one outdoor unit 30, the present invention is not limited thereto. For example, multiple indoor units 20 may be connected to one outdoor unit 30 through refrigerant pipes.

At this time, the outdoor unit 30 supplies compressed refrigerant to the connected indoor unit 20.

The indoor unit 20 receives refrigerant from the outdoor unit 30 and discharges cold air into the room. The indoor unit 20 includes an indoor heat exchanger (not shown), an indoor unit fan (not shown), an expansion valve (not shown) through which supplied refrigerant expands, and a plurality of sensors (not shown).

At this time, the outdoor unit 30 and the indoor unit 20 are connected wired or wirelessly to transmit and receive data with each other, and the outdoor unit and the indoor unit are connected wired or wirelessly to a remote controller (not shown) to be controlled by the remote controller (not shown). It can operate accordingly.

A remote control (not shown) is connected to the indoor unit 20 and can input a user's control command to the indoor unit and receive and display status information of the indoor unit. At this time, the remote control can communicate wired or wirelessly depending on the connection type with the indoor unit.

Figure 2 is a diagram illustrating a power connection between an indoor unit and an outdoor unit.

Referring to FIG. 2, the indoor unit 20 has an indoor connection part 23 connected to the indoor circuit part 21, and the outdoor unit 30 has an outdoor connection part 33 connected to the outdoor circuit part 31. can do.

The indoor connection unit 23 may be provided with an AC power (live) terminal (L), a communication terminal (C), and a neutral terminal (N).

The outdoor connection unit 33 includes a first AC power (live) terminal (L1), a second AC power (live) terminal (L2), a first neutral terminal (N1), a second neutral terminal (N2), and a communication terminal ( C) can be provided.

The first AC power terminal L1, the first neutral terminal N1, and the communication terminal C of the outdoor connection unit 33 are the AC power terminal L and the neutral terminal of the indoor connection unit 23, respectively. (N), can be connected to the communication terminal (C).

The power plug 35 is connected to an outlet supplied with commercial AC power. In the case of the outdoor lead-in wiring method in which the power plug 35 is connected to the outdoor connection unit 33, AC power is applied through the second AC power terminal (L2) and the second neutral terminal (N2), and the outdoor circuit unit ( 31) AC power is supplied.

In addition, AC power is supplied to the indoor circuit unit 21 through the first AC power terminal L1, the AC power terminal L connected to the first neutral terminal N1, and the neutral terminal N. do.

FIG. 3 is a diagram briefly illustrating a configuration for arc detection according to an embodiment of the present invention, and FIG. 4 is a diagram briefly illustrating an arc detection circuit according to an embodiment of the present invention.

5 to 8 are diagrams referenced in the description of arc detection according to an embodiment of the present invention.

2, 3, and 4, the air conditioner 100 according to an embodiment of the present invention is connected to an outlet 301 supplied with AC power 201 through a power plug 35. Connection parts 23, 33, a first voltage sensor 361 that detects the input voltage (V1) input through the connection parts 23, 33, and a signal line connected to the outlet 301 to connect to the outlet. A second voltage sensor 362 detects the supply voltage V2 of 301, and the state of the input voltage V1 detected by the first voltage sensor 361 and detected by the second voltage sensor 362. If the state of the supply voltage V2 is different, it may include a control unit 350 that stops the operation of the air conditioner 100.

Figure 2 shows an outdoor incoming wiring method in which power is input through the outdoor unit 30, and is connected to the outdoor connection unit 33 to which the power plug 35 is connected to receive AC power. In the case of the indoor incoming wiring method, the power plug 35 is connected to the indoor connection part 23, and AC power 201 is supplied through the indoor connection part 23.

The power plug 35 is connected to an outlet 301 supplied with commercial AC power 201. The power plug 35 includes a main power line through which power is supplied for operation of the air conditioner 100, and the input voltage V1 of the commercial AC power source 201 is supplied with air through the main power line. It can be input to the conditioner 100. In Figure 4, the equivalent resistance (Re) of the main power line is illustrated.

The air conditioner 100 includes a rectifier 310 that rectifies the input AC power 201 and outputs it to the DC terminal. The rectifier 310 may include a bridge diode composed of a plurality of diodes. Meanwhile, the rectifier 310 may implement a full-wave rectification circuit using a center-tap transformer and two diodes instead of using a bridge diode. However, there is an advantage that the power supply voltage is reduced by half compared to the case of using a center tap, and the magnitude of the voltage applied in the reverse direction to the non-conducting diode is also reduced by half, so a bridge diode consisting of four diodes is used to replace the rectifier (310). ) is more desirable.

A smoothing capacitor (C) 320 is connected to the output terminal of the rectifier 310. The capacitor 320 can store the power output from the rectifier 310. Since the power output from the rectifier 310 is DC power, the smoothing capacitor 320 may be called a DC stage capacitor.

The rectifier 310 is connected to the connection parts 23 and 33 and can rectify the AC power input through the connection parts 23 and 33.

The connection parts 23 and 33 may include a live terminal and a neutral terminal. The connection parts 23 and 33 are connected to the outlet 301 of the commercial AC power source 201 using three terminals, Live (L), Neutral (N), and Ground (G), respectively, to provide power. can be input. For example, the ground (G) terminal is connected to ground, and the live terminal (L) and neutral terminal (N) are connected with a power line to supply AC power to the air conditioner 100. In the case of general commercial voltage, there is almost no potential difference between neutral and ground, and there are cases where the potential difference between live and neutral is 220V, and there are cases where live and ground or neutral and ground each have a potential difference of 110V.

Meanwhile, the first and second voltage sensors 361 and 362 may sense the input voltage V1 input to the air conditioner 100 and the supply voltage V2 of the outlet 301, respectively.

The first voltage sensor 361 includes a first node (n1) between the live terminal (L) and the rectifier 310, and a second node ( It can be placed between n2).

The second voltage sensor 362 is connected to the outlet 301 through a signal line and detects the supply voltage (V2) of the outlet 301. The second voltage sensor 362 may be connected between the two power terminals (L, N) of the commercial power supply 201.

That is, the first voltage sensor 361 senses the voltage after the equivalent resistance (Re) of the main power line in the current flow, and the second voltage sensor 362 senses the equivalent resistance (Re) in the main power line in the current flow. The subsequent voltage can be sensed.

The first and second voltage sensors 361 and 362 may include a resistor element, OP AMP, etc. for voltage detection. The detected input voltage and supply voltage may be applied to the control unit 350 as a discrete signal in the form of a pulse. The first and second voltage sensors 361 and 362 may include OP AMPs that amplify the potential difference. The amplification gain can be simply set by the ratio of resistances provided in the first and second voltage sensors 361 and 362. The first and second voltage sensors 361 and 362 can also detect the zero crossing point of the input voltage (V1) and the supply voltage (V2).

The control unit 350 can control the overall operation of the air conditioner 100. The control unit 350 may include one or more microprocessors. In some cases, the control unit 350 may include a microprocessor for arc detection and a microprocessor for controlling the operation of the air conditioner 100. Meanwhile, the air conditioner 100 may further include a memory (not shown) that stores various data necessary for arc detection and control of the air conditioner 100.

The control unit 350 can operate the air conditioner 100 in response to user input and control the air conditioner 100 based on data acquired from various sensors. If an abnormal situation is determined, the control unit 350 can control the air conditioner 100 according to corresponding logic. For example, in an abnormal situation, the control unit 350 may stop the air conditioner 100. In addition, the control unit 350 can block the power supply to the air conditioner 100 by controlling a relay (not shown).

According to an embodiment of the present invention, a series arc can be detected and blocked using voltage sensing at the product end of the air conditioner 100.

When an arc occurs, the control unit 350 can stop the air conditioner 100. Additionally, when an arc occurs, the control unit 350 can stop the compressor.

The control unit 350 may continuously monitor the difference between the input voltage (V1) and the supply voltage (V2) sensed by the first and second voltage sensors 361 and 362.

If the states of both the input voltage V1 and the supply voltage V2 are normal, the control unit 350 can maintain the current operating state. Figure 5 illustrates a steady-state voltage waveform.

If an abnormal situation is determined, the control unit 350 can stop the product. The control unit 350 can at least stop the compressor. The control unit 350 may stop the compressor when the input voltage (V1) and the supply voltage (V2) are different.

If the state of the input voltage (V1) and the state of the supply voltage (V2) are different, and the state of the input voltage (V1) corresponds to a distorted waveform, the control unit 350 may determine it to be an arc. In addition, if the state of the input voltage (V1) and the state of the supply voltage (V2) are different, and the state of the supply voltage (V2) corresponds to a distorted waveform, the control unit 350 determines that the signal line is abnormal. can do.

The supply voltage (V2) is a steady waveform, but if the input voltage (V1) is distorted, an arc has occurred, and the control unit 350 can stop the product/compressor.

Alternatively, if the input voltage (V1) is a normal waveform but the supply voltage (V2) is distorted, there is a problem with the signal line, and the control unit 350 can stop the product/compressor.

6A and 6B illustrate voltage waveforms in a distorted state. Referring to FIG. 6A, it can be seen that voltage distortion occurs due to the arc occurring during the arc time. Referring to Figure 6b, it can be seen that distortion of the input voltage and current occurs when an arc occurs.

The control unit 350 can control to maintain the operation state when the input voltage (V1) state and the supply voltage (V2) state are the same. If the input voltage (V1) state and the supply voltage (V2) state are the same, the control unit 350 maintains an operating state even if the input voltage (V1) state and the supply voltage (V2) state correspond to a distorted waveform. It can be maintained.

When the input voltage V1 and the supply voltage V2 are in the same distorted state, the control unit 350 may determine that harmonics have been introduced into the input voltage rather than an arc occurring. Even if distortion occurs in the input voltage, if the input voltage (V1) and supply voltage (V2) are the same, normal operation is possible because no arc has occurred.

As in previous literature, it takes time to detect when a conventional arc current occurs. Therefore, if you focus on quickly capturing the arc current, you can block the current even in situations where no arc occurs. In this case, the product may malfunction. If the detection time is increased to accurately capture the arc current, there is a possibility of a fire.

Figure 7 shows the time that must be interrupted per arc current of the UL 1699 safety standard, and Figure 8 shows the probability of wire ignition according to the interruption time. The blocking time may be the sum of the opening time and arc time in FIG. 6A. Opening Time is the time from the moment the trip control device (coil) of the breaker in the closed state is excited until the arc contactor (or main contactor) opens, and Arc Time is the time when the breaker arc occurs. This is the time from the moment the contactor (or main contactor) is separated to the moment the current in all poles is cut off. Even if the arc is blocked normally according to UL standards, a fire may occur. Therefore, when an arc occurs, the current must be cut off as quickly as possible.

According to an embodiment of the present invention, by comparing the voltage at both ends of the power line (Re), it is possible to check whether an arc has occurred and to quickly respond.

The air conditioner 100 according to an embodiment of the present invention may further include an output unit (not shown) that outputs an operating state and a warning according to a control command from the control unit 350.

When an arc is detected, the control unit 350 can output the fact that the arc has occurred through an output unit. The control unit 350 may output the fact of arc occurrence through a display means or an audio output unit. When an arc occurs, the control unit 350 can generate and output an arc error and stop the product.

According to an embodiment of the present invention, a fire can be prevented by stopping the product when an arc current occurs. Measure the difference between the power cord (wall voltage) and the voltage connected to the air conditioner, and if a difference occurs, it is considered that an arc has occurred, and the air conditioner operation can be stopped and the user notified. Therefore, according to the present invention, unlike conventional AFCI circuit breakers, immediate response is possible when an arc occurs.

The air conditioner according to the present invention is not limited to the configuration and method of the embodiments described above, but all or part of the embodiments are selectively combined so that various modifications can be made. It may be configured.

In addition, although preferred embodiments of the present invention have been shown and described above, the present invention is not limited to the specific embodiments described above, and the technical field to which the invention pertains without departing from the gist of the present invention as claimed in the claims. Of course, various modifications can be made by those skilled in the art, and these modifications should not be understood individually from the technical idea or perspective of the present invention.

Claims (8)

A connection part connected to an outlet supplied with alternating current power through a power plug;
a first voltage sensor that detects an input voltage input through the connection unit;
a second voltage sensor connected to the outlet with a signal line to detect the supply voltage of the outlet; and,
An air conditioner comprising: a control unit that stops operation of the air conditioner when the input voltage state sensed by the first voltage sensor is different from the supply voltage state sensed by the second voltage sensor. According to paragraph 1,
The control unit,
An air conditioner that stops the compressor when the input voltage state and the supply voltage state are different. According to paragraph 1,
The control unit,
The input voltage state and the supply voltage state are different,
An air conditioner that determines the input voltage state as an arc when it corresponds to a distorted waveform. According to paragraph 1,
The control unit,
The input voltage state and the supply voltage state are different,
An air conditioner that determines that the signal line is abnormal when the supply voltage state corresponds to a distorted waveform. According to paragraph 1,
The control unit,
An air conditioner that is controlled to maintain an operating state when the input voltage state and the supply voltage state are the same. According to paragraph 1,
The control unit,
If the input voltage state and the supply voltage state are the same,
An air conditioner that is controlled to maintain an operating state even if the input voltage state and the supply voltage state correspond to a distorted waveform. According to paragraph 1,
A rectifier connected to the connection unit and rectifying the alternating current power input through the connection unit; and
An air conditioner further comprising a DC terminal capacitor connected to the output terminal of the rectifier. According to paragraph 1,
An air conditioner further comprising an output unit that outputs an operation status and a warning according to a control command from the control unit.

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