JP2008116155A - Operation control method for air conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an operation control method for an air conditioner for stably carrying out compressor drive control without requiring man-hours for software development, in the air conditioner performing defrosting operation for removing frost sticking onto an outdoor heat exchanger while continuing heating. <P>SOLUTION: The method comprises a compressor rotation speed change means, which changes a rotation speed of a compressor to a predetermined rotation speed, and a compressor rotation speed change control time decision output means deciding the time for changing the rotation speed of the compressor and outputting the time are installed. Based on the outputs from the compressor rotation speed change means and the compressor rotation speed change control time decision output means, the rotation speed of the compressor is changed to a predetermined rotation speed during a predetermined period before applying electric power to a heat generation part in a refrigerant heater. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an air conditioner that performs a defrosting operation for defrosting frost attached to an outdoor heat exchanger while continuing heating.

  Conventionally, there are the following inventions as an air conditioner that performs a defrosting operation while continuing heating.

As shown in FIG. 1, a heat pump refrigeration cycle in which a compressor, a four-way valve, an indoor heat exchanger, a decompressor, and an outdoor heat exchanger are connected by a refrigerant circuit, and the indoor heat exchanger connected to the refrigeration cycle, A first bypass circuit that connects between the pressure reducer, the four-way valve, and the outdoor heat exchanger is provided; a first two-way valve and a refrigerant heater are provided in the first bypass circuit; and A second bypass circuit is provided to connect the four-way valve and the indoor heat exchanger connected to the refrigeration cycle, and between the pressure reducer and the outdoor heat exchanger, and the second bypass circuit includes a second bypass circuit. When the defrosting of the outdoor heat exchanger is performed, the two-way valve of the first bypass circuit is opened and the refrigerant heated by the refrigerant heater is allowed to flow to the suction side of the compressor After a certain time after the first bypass operation, the second bypasser A second bypass operation for opening the two-way valve of the circuit and allowing the refrigerant to pass through the outdoor heat exchanger is performed, and defrosting while continuing the heating operation by making this configuration (For example, refer patent document 1).
And as this applied technology, before defrosting, the heat generating part of the refrigerant heater is energized to store heat in the refrigerant heater, and then the first two-way valve of the first bypass circuit is opened to produce the refrigerant. There is a method of flowing the refrigerant heated by the heater to the suction side of the compressor, and when this technique is used, the heating part of the refrigerant heater is energized as shown in the time chart of the control of the prior art in FIG. Before step 3, by providing step 2 in which the operating current control value is reduced to forcibly reduce the compressor rotational speed and then the heat generating portion of the refrigerant heater is energized, the refrigerant is heated within the current capacity range. The technology devised to energize the device is installed, and these technologies are widely used.
JP 2006-132729 A

  However, in the prior art, when the operating current control value is reduced to forcibly reduce the compressor rotational speed before energizing the heat generating part of the refrigerant heater, the compressor rotational speed changes suddenly, thereby reducing the compression. The machine drive control surface becomes unstable, and in the worst case, a step-out phenomenon occurs and the compressor operation is stopped.

  To solve this problem, it is only necessary to install a control that can follow the compressor drive control even when the load suddenly changes. In this case, the control becomes complicated, and if the refrigeration cycle capacity is changed, the drive control is also performed accordingly. There was a problem that it was necessary to re-tune, and as a result, the man-hours for software development increased.

  The present invention has been made in view of such problems of the prior art, and provides an air conditioner operation control method that is stable on the compressor drive control surface without increasing the number of steps for software development. It is aimed.

In order to achieve the above object, the air conditioner operation control method of the present invention comprises a compressor having a variable speed, a four-way valve, an indoor heat exchanger, a decompressor, and an outdoor heat exchanger connected by a refrigerant circuit. A heat pump refrigeration cycle, and a first bypass circuit that connects between the indoor heat exchanger and the decompressor connected to the refrigeration cycle, and between the four-way valve and the outdoor heat exchanger, A first bypass circuit is provided with a first two-way valve and a refrigerant heater, and further, a second bypass connecting between the four-way valve and the indoor heat exchanger and between the pressure reducer and the outdoor heat exchanger. A circuit is provided, and the second bypass circuit is arranged in the order of the second two-way valve and the check valve from the four-way valve side, and the check valve is a refrigerant from the second two-way valve side. The refrigerant is arranged to flow only before the defrosting of the outdoor heat exchanger After energizing the heat generating part of the heater and storing the heat in the refrigerant heater, the first two-way valve of the first bypass circuit is opened and the refrigerant heated by the refrigerant heater is sucked into the compressor Air for performing a first bypass operation for flowing to the side and a second bypass operation for opening the second two-way valve of the second bypass circuit and allowing the refrigerant to pass through the outdoor heat exchanger. In the harmony device, a compressor rotation speed changing means for changing the rotation speed of the compressor to a predetermined rotation speed, and a compressor rotation speed change control time determination output for determining and outputting a time for changing the rotation speed of the compressor Means for changing the rotational speed of the compressor before energizing the heat generating portion of the refrigerant heater by means of outputs from the compressor rotational speed changing means and the compressor rotational speed change control time determination output means. Change to a certain number of revolutions for a certain period of time It is characterized in.

  By using the above means, it is possible to achieve stable compressor drive control while maintaining the conventional control without taking the effort of software development.

  Furthermore, the operation control method for an air conditioner according to the present invention is characterized in that the time for changing the rotational speed of the compressor is changed while reading the rotational speed of the compressor, the indoor and outdoor temperatures.

  By using the above means, the rotation speed of the compressor is changed for an optimum time according to the operation load of the air conditioner, so that the operation can be controlled at the optimum time for each load.

  The operation control method for an air conditioner according to the present invention is a stable compressor that does not require software development man-hours for an air conditioner that performs a defrosting operation that defrosts frost attached to an outdoor heat exchanger while continuing heating. Drive control can be performed.

  The first invention is a compressor having a variable rotation speed, a heat pump refrigeration cycle in which a four-way valve, an indoor heat exchanger, a decompressor, and an outdoor heat exchanger are connected by a refrigerant circuit, and the refrigeration cycle. A first bypass circuit is provided to connect between the indoor heat exchanger and the pressure reducer, and between the four-way valve and the outdoor heat exchanger, and the first two-way valve and the refrigerant heating are provided in the first bypass circuit. A second bypass circuit that connects the four-way valve and the indoor heat exchanger, and between the pressure reducer and the outdoor heat exchanger, and the second bypass circuit includes the second bypass circuit, Arranged in the order of the second two-way valve and the check valve from the four-way valve side, the check valve is arranged so that only the refrigerant from the second two-way valve side flows, and the outdoor heat exchanger Before defrosting, energize the heat generating part of the refrigerant heater to store heat in the refrigerant heater. A first bypass operation in which the first two-way valve of the first bypass circuit is opened and the refrigerant heated by the refrigerant heater is caused to flow to the suction side of the compressor; and In the air conditioner, wherein the second two-way valve is opened to allow the refrigerant to pass through the outdoor heat exchanger, and the rotation speed of the compressor is changed to a predetermined rotation speed. And a compressor rotation speed change control means for determining and outputting a time for changing the rotation speed of the compressor. The compressor rotation speed change means, and the compressor rotation speed are provided. The rotation speed of the compressor is changed to a predetermined rotation speed for a predetermined time period before the power supply to the heat generating portion of the refrigerant heater is performed by the output from the number change control time determination output means. By configuring the Without taking man-hours while conventional control, it is possible to stabilize the compressor drive control.

  According to the second to third aspects of the invention, the air conditioner is configured by changing the compressor rotation speed, the indoor / outdoor temperature, and changing the time for changing the rotation speed of the compressor while reading. Since the rotation speed of the compressor is changed only for the optimum time according to the operation load, the operation can be controlled at the optimum time for each load.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment)
FIG. 1 is a configuration diagram of an air conditioner according to an embodiment of the present invention, FIG. 2 is a control block diagram, FIG. 3 is a control flowchart, and FIG. 4 is a control time chart.

  In FIG. 1, an outdoor unit 20 includes a compressor 1, a four-way valve 2, a pressure reducer 4, an outdoor heat exchanger 5, a first bypass circuit 6, and a first bypass circuit that can change the number of rotations. Two-way valve 7, refrigerant heater 8, second bypass circuit 9, second two-way valve 10 in the second bypass circuit, check valve 11, refrigerant heater 13, refrigerant passage pipe section 14, heat storage section 15 An outdoor temperature sensor 21 is disposed on the upwind side of the ventilation path of the outdoor fan 19 and the outdoor heat exchanger. In the indoor unit 18, an indoor temperature sensor 22 is disposed on the windward side of the ventilation path of the indoor heat exchanger 3, the indoor blower 17, and the indoor heat exchanger. The decompressor 4 here may be an electromagnetic expansion valve.

  Next, the flow of control will be described with reference to FIGS.

  When the air conditioner is heated and frost is formed on the outdoor heat exchanger 5 and frost is formed on the whole, a defrost start signal is transmitted. When the defrost start signal is received, the process proceeds from step 0 to step 1 and defrost control is started. (S301).

  The calculation unit in the microcomputer 23 calculates the time ta for changing the compressor speed from the compressor speed change control time determination output means (S305), and determines the time ta (= t0) for changing the compressor speed. (S306) The change to the compressor low-speed rotation setting is performed by the compressor rotation speed changing means for ta time (S307). In this case, since the rotational speed of the compressor is operated at an optimal rotational speed change speed as compressor drive control, the compressor can be stably operated in terms of drive performance.

  If the change time ta has passed, the process proceeds to step 2, but with regard to the set value of the compressor rotation speed, the rotation speed corresponding to the current when the refrigerant heater is energized after step 2 at the maximum load of the refrigeration cycle. Since the compressor rotation speed change time ta is set based on the change speed time from the compressor maximum rotation speed to the set rotation speed, the compressor rotation speed is set to the set rotation at step 2 Since the rotational speed is reduced to a certain number, stable compressor drive control can be realized without a sudden change in the rotational speed.

  Further, in the microcomputer 24, the compressor rotational speed f is detected by the compressor rotational speed reading output means (S302), the indoor temperature Tin is detected by the indoor temperature reading output means (S303), and the outdoor temperature is read by the outdoor temperature reading output means. Tout is detected (S304), and the values of f, Tin, and Tout are read by the calculation unit. When a predetermined condition is satisfied, a correction value is added to the compressor rotation speed change time ta (ta = t0 + (+ a -B + c)) (S305), the time ta for changing the compressor speed is determined (S306), and the change to the compressor low speed setting is performed by the compressor speed changing means for ta time (S307). Thereby, the setting of the rotation speed of the compressor can be changed in an optimum time according to the operation load of the air conditioner, and the operation can be controlled in the optimum time for each load.

Configuration diagram of an air conditioner according to the present invention Control block diagram according to the present invention The flowchart of embodiment concerning this invention Time chart of embodiment according to the present invention Time chart of conventional air conditioner operation control method

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Compressor 2 Four-way valve 3 Indoor heat exchanger 4 Pressure reducer 5 Outdoor heat exchanger 6 1st bypass circuit 7 1st two-way valve 8 Heater 9 2nd bypass circuit 10 2nd two-way valve 11 Reverse Stop valve 12 Refrigerant heating decompressor 13 Heater heater 14 Refrigerant passage tube 15 Thermal storage unit 17 Indoor fan 18 Indoor unit 19 Outdoor fan 20 Outdoor unit 21 Outdoor temperature sensor 22 Indoor temperature sensor 23 Microcomputer

Claims (3)

A compressor having a variable speed, a heat pump refrigeration cycle in which a four-way valve, an indoor heat exchanger, a decompressor, and an outdoor heat exchanger are connected by a refrigerant circuit, and the indoor heat exchanger connected to the refrigeration cycle A first bypass circuit that connects between the pressure reducer, the four-way valve, and the outdoor heat exchanger is provided; a first two-way valve and a refrigerant heater are provided in the first bypass circuit; and A second bypass circuit is provided to connect between the four-way valve and the indoor heat exchanger, and between the pressure reducer and the outdoor heat exchanger, and the second bypass circuit includes a second bypass circuit from the four-way valve side. The two-way valve and the check valve are arranged in this order, the check valve is arranged so that only the refrigerant from the second two-way valve side flows, and before defrosting the outdoor heat exchanger The first heating unit is energized to store heat in the refrigerant heater, and then the first A first bypass operation in which the first two-way valve of the bypass circuit is opened and the refrigerant heated by the refrigerant heater flows to the suction side of the compressor, and the second two-way valve of the second bypass circuit In the air conditioning apparatus, wherein a second bypass operation is performed in which the refrigerant is passed through the outdoor heat exchanger and the compressor rotational speed is changed to a predetermined rotational speed. And a compressor rotation speed change control time determination output means for determining and outputting a time for changing the rotation speed of the compressor, the compressor rotation speed change means, and the compressor rotation speed change control time determination output An air conditioner characterized in that the rotational speed of the compressor is changed to a predetermined rotational speed for a predetermined time before the heating of the heat generating part of the refrigerant heater is energized by the output from the means. Operation control method. Compressor rotation speed reading output means for reading and outputting the rotation speed of the compressor is provided, and the time for changing the rotation speed of the compressor is changed by the output from the compressor rotation speed reading output means. The operation control method of the air conditioner according to claim 1. The indoor temperature reading output means for reading and outputting the indoor temperature at the suction port of the indoor heat exchanger, and the outdoor temperature reading output means for reading and outputting the outdoor temperature at the suction port of the outdoor heat exchanger, the indoor temperature reading output The operation control method for an air conditioner according to claim 1 or 2, wherein the time for changing the rotational speed of the compressor is changed by means of the means and the output from the outdoor temperature reading output means.

Images