JPS5818567B2 - How to operate an air conditioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an air conditioner that uses a common electric motor for different rated voltage conditions.

For example, electric compressors used in air conditioners for export have many rated voltages, and manufacturing motors with different specifications for each rated voltage increases the variety of products, which is undesirable in terms of production costs and inventory management.

In addition, if several similar rated voltages are treated as one voltage category and used with the same load, the lower voltage side will suffer from insufficient output, and the higher voltage side will have a poor power factor at low loads. There are some problems involved.

Next, an example of a usage state of a conventional electric compressor in which the same motor is used for two rated voltages will be explained with reference to FIG.

In the figure, the horizontal axis represents voltage, and the vertical axis represents current and motor output.

In Figure 1, if point A has a lower voltage than point B, then
For the same load, the higher the voltage, the smaller the current, and
The motor output increases as the voltage increases.

Therefore, when used with the same load at voltages A and B as in the past, if the maximum load is at point 3 at voltage A, there will be a margin of 4-5 at voltage 'B, and the motor will be wasted. , and voltage A when using a protection device that senses current value.

Since the current value is different in B, it is impossible to use a protection device with the same operating value.

In FIG. 1, point 2 corresponds to the current value at voltage A, and point 6 corresponds to point 5 at voltage A.

This invention is intended to eliminate the above-mentioned drawbacks.The present invention is designed to eliminate the above-mentioned drawbacks by adjusting the motor output at each voltage using the same motor for multiple rated voltages, using the higher voltage one under heavy load conditions, and the lower voltage one. used under conditions with a smaller load than that, and
The current value under both overload conditions is the same, and the protection device based on the current value has the same specifications.

Hereinafter, one embodiment of the present invention will be explained with reference to FIG.

In the figure, the horizontal and vertical axes represent the same things as in FIG. 1, respectively.

Match the motor output 3 at low voltage A with a specification with a small load (for example, when the condensing method of the air conditioner is a water cooling type), and match the motor output 5 at high voltage B with a specification with a large load (for example, when the condensing method of the air conditioner is a water cooling type). (e.g., when the condensing method of the machine is air-cooled), and the current value 2 for the specification with a small load at voltage A and the current value 1 for the specification with a large load at voltage B.
′ are chosen equally.

This makes it possible to reduce the number of types of electric motors, achieve an inexpensive and optimal design without adding any extra margin to the electric motor, and use the same protection device that operates based on the current value.

Note that 1 is the current value at voltage B for specifications with a small load.

According to the invention described above, the following effects can be obtained.

(1) Since the same electric motor and the same protection device can be used even if the rated voltages are different, it is possible to reduce the types of electric motors and electric compressors incorporating them, and to reduce manufacturing costs and management costs.

(2) The method of use matches the motor output, and the motor can be made inexpensive and compact with no extra margin.

[Brief explanation of drawings]

FIG. 1 is a graph illustrating usage conditions of a conventional electric compressor, and FIG. 2 is a graph illustrating usage conditions of an electric compressor according to the present invention. 1... Current value for specifications with small load at voltage B, 1'... Current value for specifications with large load at voltage B, 2... Current value for specifications with large load at voltage A. Specification current value, 3...motor output at low voltage A, 5...motor output at high voltage B.

Claims (1)

[Claims] 1. In an air conditioner in which a refrigeration cycle is formed by connecting in series an electric compressor, a condenser, an expansion valve, and an evaporator that have a common electric motor that can be used at different rated voltages, the current value of the electric motor is The setting value of the protective device to be detected is set to be almost the same for different rated voltage conditions, and where the motor is operated at a high rated voltage, the condenser of the air conditioner is an air-cooled condenser, and when the motor is operated at a high rated voltage, the condenser of the air conditioner is an air-cooled condenser. A method for operating an air conditioner, characterized in that the condenser is used as a water-cooled condenser when the air conditioner is operated.