JPH01270794A - Operation controller for air conditioner - Google Patents

Abstract

PURPOSE:To optimally set a torque, to operate in a low frequency range, to further reduce an input, and to improve feeling at the time of operation by varying an input voltage in response to a load at the time of low frequency operation. CONSTITUTION:A DC current detector 11 detects a load current of a compressor 16, and inputs it to a LSI 13. The LSI 13 contains a comparator, a discriminator, a calculator, and a memory for storing compressor rotating speed controllers I, II (frequency/voltage characteristics I, II). The LSI 13 compares a DC current value with a set DC current value to discriminates it, and drives a power transistor 14. Thus, the input voltage of the compressor 16 is varied corresponding to the load of the compressor 16 and hence a DC current value to optimally set a torque.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an operation control device for an air conditioner equipped with a frequency converter.

Conventional technology In recent years, air conditioners equipped with frequency converters have been designed with a wide set frequency range to widen the variable range of cooling/heating capacity (to improve the feeling during operation or to save energy during operation). I know.

An example of the above-mentioned conventional air conditioner equipped with a frequency converter will be described below with reference to the drawings.

FIG. 6 and FIG. 7 show a conventional refrigeration cycle diagram and an electric circuit diagram, respectively.

In FIG. 6, 101 is a compressor, 102 is a four-way valve, 1
03 is an indoor heat exchanger, 104 is a pressure reducing device, and 105 is an outdoor heat exchanger.

In FIG. 7, 106 is a power supply device including a noise filter, a diode bridge, etc., 107 is a power transistor device, and 108 is a microcomputer.

The operation of the air conditioner equipped with a frequency converter having the above configuration will be described below.

First, the power transistor device 10 generates a three-phase waveform from unequal width pulses output from the microcomputer 108, and the three-phase compressor 101 is driven. Further, the frequency-voltage characteristics shown in FIG. 5 are set and operated based on the pulse width and period output from the microcomputer 108.

Problems to be Solved by the Invention However, with the above configuration, due to problems such as the torque of the compressor 101, the minimum rotational speed at which the compressor can be operated is limited, especially in the low frequency range where the influence of the load is large, resulting in low performance during cooling and heating. The problem was that it was difficult to pursue human resources.

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention aims to provide an improved feeling during operation and energy savings by pursuing a variable range of power input during heating and cooling, especially low power input.

Means for Solving the Problems In order to solve the above problems, the air conditioner operation control device of the present invention includes a DC current detection means for detecting a DC current value flowing through the outdoor unit, and a voltage value of the DC current detection means. and setting D
A comparison means that compares and determines the voltage value of the C current value and outputs an H-L control signal, and determines whether the operating frequency of the compressor and the set frequency are the same value, and outputs an H-L control signal. a determining means, a calculating means for calculating a combination of the control signal of the comparing means and the control signal of the determining means, and operating the compressor according to numerical control according to the H-L control signal output from the calculating means. It is equipped with an output means for outputting the information.

Effects According to the present invention, with the above-described configuration, the compressor is operated at a specified low frequency, and the compressor rotation speed control can be changed in response to load changes (DC current value changes). The variable range can be increased, making it possible to achieve low-performance input values during cooling and heating, which were not possible with conventional air conditioners equipped with frequency converters.

Embodiment Hereinafter, an embodiment of the operation control device for an air conditioner equipped with a frequency converter according to the present invention will be described with reference to the drawings.

FIG. 1 shows a circuit diagram of an operation control device for an air conditioner equipped with a frequency converter according to an embodiment of the present invention.

In FIG. 1, 11 is a DC current detection circuit, 12 is a resistor circuit for setting DC current value, and 13 is a microcomputer (
(hereinafter referred to as LSI), 14 is a power transistor device;
15 is a power supply device including a power supply, a fuse, a noise filter, a diode bridge, etc., and 16 is a three-phase compressor.

The operation of the operation control device for an air conditioner equipped with a frequency converter configured as described above will be described below with reference to FIGS. 1 to 4.

FIG. 2 is a block diagram representing the control device using function realizing means, and the relationship with each component shown in FIG. 1 is shown below.

The DC current detection circuit 11 shown in FIG. 1 corresponds to the DC current detection means, and the set DC current value resistor circuit 12 corresponds to the set DC current value. In addition, the comparison circuit built in the LS113 serves as a comparison means, the judgment circuit built in the LS113 serves as a judgment means, the arithmetic circuit built in the LS113 serves as a calculation means, and the compressor rotation built in the LS113 Number control 1. A memory circuit that stores n (frequency-voltage characteristic 1.11) corresponds to the memory means. Furthermore, the power supply device 15
and the power transistor device 14 correspond to output means.

Read, compare and judge the operating frequency and set frequency,
If the frequency is the same, the read DC current value and setting DC
Compare and judge the current value, and only if it is larger than the set DC current value, select the compressor rotation speed control (r-v characteristic I),
Drive the power transistor device. In other cases, the compressor rotation speed control [(f-Vk characteristic I) is selected and the power transistor device is driven.

As described above, according to this embodiment, in an air conditioner equipped with a frequency converter, the input voltage of the compressor is changed in accordance with the load of the compressor, that is, the DC current value during low frequency operation, so that torque can be increased. can be set optimally, making it possible to operate in a low frequency range, and furthermore, reducing input power and improving the driving feeling.

Effects of the Invention As described above, the present invention provides an air conditioner that responds to compressor load (DC current value change) during low frequency operation.
By changing the input terminal of the compressor, the torque can be set optimally, making it possible to operate in a low frequency range.
Furthermore, it is possible to reduce input power and improve the driving feeling.

[Brief explanation of the drawing]

Fig. 1 is an electrical circuit diagram of an operation control device for an air conditioner equipped with a frequency converter according to an embodiment of the present invention, Fig. 2 is a block diagram expressing the operation control device as a function realizing means, and Fig. 3 is 4 is a frequency-voltage characteristic diagram of the same control device, FIG. 5 is a frequency-voltage characteristic diagram of a conventional air conditioner equipped with a frequency converter, and FIG. 6 is a refrigeration cycle diagram. FIG. 7 is a conventional electrical circuit diagram. 11...DC current detection circuit, 12...Resistance circuit for setting DC current value, 13...Microcomputer, 14...Power transistor device, 15... ...Power supply device, 16...Three-phase compressor. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 3
figure? s4 diagram rotation &: f (Hz) Fig. 5 ff fall + ('Z) 101° - three-phase pressure = * 10E・-external control focus intersection # Tomoe Fig. 6 /

Claims (1)

[Claims] A refrigeration cycle is constructed in which a compressor, a four-way valve, an indoor heat exchanger, a pressure reducing device, and an outdoor heat exchanger are connected in a ring, and a DC current detection means for detecting a DC current value flowing through the outdoor unit; The comparison means compares and determines the voltage value of the detection means and the voltage value of the set DC current value, and outputs the H/L control signal, and the comparison means determines whether the operating frequency of the compressor is the same as the set frequency, and outputs the H/L control signal. determining means for outputting a control signal of L; a calculating means for performing a combination calculation of the control signal of the comparing means and the control signal of the determining means;
・According to the control signal L, either compressor rotation speed control I or II built in the storage means is selected, and output means is provided for operating the compressor according to the selected compressor rotation speed control. Operation control device for air conditioners.