JPH0463977B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a control device for determining the maximum operating frequency of a variable capacity air conditioner.

BACKGROUND ART In recent years, variable capacity air conditioners have become increasingly popular, and various control devices have been devised to optimally operate them.

An example of the above-mentioned air conditioner control device will be described below with reference to the drawings.

FIG. 4 is a configuration diagram of a conventional maximum operating frequency control device for a variable capacity air conditioner.

In the figure, 1 is a room temperature detection means, 11 is a room temperature detection value, 2 is a maximum operating frequency determination means, and 21 is a room temperature comparison means, which compares the room temperature detection value 11 detected by the room temperature detection means 1 and the room temperature reference value Ti. Comparison means 21
Based on the comparison, the maximum operating frequency determination means 2 issues a maximum operating frequency instruction.

The operation of the air conditioner control device configured as described above will be described below.

First, during heating operation of a variable capacity air conditioner,
Room temperature detection value 11 detected by room temperature detection means 1
is input to the room temperature comparison means 21, and the room temperature reference value Ti
compared to

At this time, conventionally, as shown in Figure 5, the room temperature was
The maximum operating frequency was controlled to be Fmax if it was below Ti, and FH if it was Ti or more. here
FH is the operating frequency at which the air conditioner exhibits its standard performance during heating operation, and was determined in consideration of the fact that the operating current does not exceed the limit value even when the room temperature and outside temperature are high, so-called heavy loads. It is. Further, Fmax is the operating frequency at which the air conditioner exhibits its maximum capacity (for example, Japanese Patent Laid-Open No. 58-228724).

Problems to be Solved by the Invention In the above configuration, only the room temperature is detected, so even when the outside temperature is low, if the room temperature is Ti or higher, the maximum operating frequency is FH.

However, when the outside temperature is low, the load is light and the operating current is reduced, making it possible to operate at a higher frequency, which poses the problem that conventional control devices cannot reach the full potential of the air conditioner. was.

In view of the above-mentioned problems, the present invention detects the room temperature and the outside temperature, and determines the maximum operating frequency from both of them. The objective is to provide a control device that more effectively utilizes the capabilities of the system.

Means for Solving the Problems In order to solve the above problems, the present invention includes a room temperature detection means, a room temperature comparison means for comparing a room temperature detection value detected by the room temperature detection means with a room temperature reference value,
The device comprises an outside temperature detection means and an outside temperature comparison means for comparing an outside temperature detection value detected by the outside temperature detection means with an outside temperature reference value, and the room temperature detection value is lower than the room temperature reference value during heating operation. or when the outside temperature detected value is lower than the outside temperature reference value, the maximum operating frequency instruction is permitted up to the maximum operating frequency Fmax of the compressor, and when the room temperature detection value is higher than the room temperature reference value and the A maximum operating frequency determining means is provided that limits the maximum operating frequency instruction to a frequency lower than the Fmax when the detected outside temperature value is higher than the outside temperature reference value, and allows stable operation even when the refrigeration cycle is overloaded. It is something.

Effects According to the present invention, with the above-described configuration, during the heating operation of the variable capacity air conditioner, if the outside temperature is low even if the room temperature is Ti or higher, this is detected by the outside temperature detection means, and the maximum operating frequency is set to Fmax. Maximum heating capacity will be obtained.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows the configuration of an air conditioner control device in an embodiment of the present invention.

In FIG. 1, 1 is a room temperature detection means, 11 is a detected room temperature value, 2 is a maximum operating frequency determining means, 21 is a room temperature comparison means, 22 is an outside temperature comparison means, 3 is an outside temperature detection means, and 31 is an outside temperature detection means. It is a value. The room temperature detection value 11 and the room temperature reference value Ti are determined by the room temperature comparison means 21,
The outside temperature detection value 31 and the outside temperature reference value To are compared by the outside temperature comparison means 22, and based on this, the maximum operation frequency determination means 2 issues a maximum operation frequency instruction.

The operation of the air conditioner control device configured as described above will be described below with reference to FIGS. 1 to 3.

First, Figure 2 shows the relationship between room temperature, outside temperature, and maximum operating frequency during heating operation.When the room temperature is Ti or higher and the outside temperature is To or higher, the maximum operating frequency is FH.
This indicates that when the room temperature and outside temperature are outside the above range, Fmax is set.

FIG. 3 is a determination flowchart of the maximum operating frequency determining means 2 during heating operation. The operation will be explained below based on the flowchart.

First, the room temperature detection value 11 detected by the room temperature detection means 1 and the outside temperature detection value 31 detected by the outside temperature detection means 3 are input to the room temperature comparison means 21 and the outside temperature comparison means 22, respectively. Next, the room temperature detection value 11 is compared with the room temperature reference value Ti by the room temperature comparison means 21, and if the room temperature detection value 11 is less than or equal to Ti, the maximum operating frequency instruction is set to Fmax. Also, room temperature detection value 1
1 is greater than or equal to Ti, the outside temperature detection value 31 and the outside temperature reference value To are further compared by the outside temperature comparison means 22,
If the outside temperature detection value 31 is greater than or equal to To, the maximum operating frequency instruction is FH, and if it is greater than To, the maximum operating frequency instruction is Fmax.

As described above, according to this embodiment, by providing the room temperature and outside temperature detection means, the room temperature and outside temperature comparison means, and the maximum operating frequency determination means, even if the room temperature is Ti or higher during heating operation, the outside temperature is
If it is below, the maximum operating frequency is Fmax, and the maximum heating capacity can be obtained.

Effects of the Invention As described above, the present invention provides a room temperature detection means, an outside temperature detection means, and a maximum operating frequency determination means having a comparison means for comparing these detected values with respective reference values. Even if the room temperature is above the room temperature standard value Ti, if the outside temperature is below the outside temperature standard value To, the maximum operating frequency is set to Fmax.
This allows maximum heating capacity to be achieved at low outside temperatures. In addition, since the room temperature reference value and the outside temperature reference value are absolute values, it is possible to detect whether the indoor temperature is higher or lower than the reference value, regardless of the indoor temperature set by the user. Since overload conditions can be accurately determined, the air conditioner can always operate at its maximum capacity without strain.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of a maximum operating frequency control device during heating operation of an air conditioner in an embodiment of the present invention;
FIG. 2 is a diagram showing the relationship between room temperature, outside temperature, and maximum operating frequency during heating operation in the embodiment of the present invention, FIG. 3 is a flowchart for determining the frequency of the maximum operating frequency determining means of FIG. 1, and FIG. 4 5 is a configuration diagram of a maximum operating frequency control device during heating operation of a conventional air conditioner, and FIG. 5 is a diagram showing the relationship between room temperature, outside temperature, and maximum operating frequency during conventional heating operation. 1... Room temperature detection means, 2... Maximum operating frequency determination means, 3... Outside temperature detection means, 21... Room temperature comparison means, 22... Outside temperature comparison means.

Claims (1)

[Claims] 1. A room temperature detection means, a room temperature comparison means for comparing the room temperature detection value detected by the room temperature detection means with a room temperature reference value, an outside temperature detection means, and an outside temperature detection value detected by the outside temperature detection means. and an outside temperature comparison means for comparing the outside temperature reference value with the outside temperature reference value, and when the room temperature detection value is lower than the room temperature reference value during heating operation, or when the outside temperature detection value is lower than the outside temperature reference value, The maximum operating frequency instruction is permitted up to the maximum operating frequency Fmax of the compressor, and if the detected room temperature value is higher than the room temperature reference value and the detected outside temperature value is higher than the outside temperature reference value, the maximum operating frequency instruction is issued. A control device for an air conditioner, comprising a maximum operating frequency determining means that limits the frequency to a lower frequency than the Fmax and allows stable operation even when the refrigeration cycle is overloaded.