JPH05236777A - Controller for air-conditioner - Google Patents

Abstract

PURPOSE:To make it possible to follow up a target number of revolution quickly by retrieving a memory table based on the time variation rate of the number of revolution of an indoor fan and the difference between a detected number of revolution and a target number of revolution thereby setting a sampling time and then performing number of revolution control of a motor at thus set sampling time. CONSTITUTION:In the controller for controlling the phase of a fan motor 3 in an indoor unit, when modification of air flow is commanded at an indoor control section 5 the number of revolution at that time is detected through a number of revolution detecting circuit 4 and the number of revolution of the motor 3 is varied at a time variation rate toward a target number of revolution during a preset sampling time (t1). At the same time, a number of revolution comparing circuit 7 determines the difference between the target number of revolution and a detected number of revolution while a time variation rate calculating circuit 9 determines the time variation rate of the number of revolution and then a sampling time (t2) is set by retrieving a table in a memory 8. Upon elapse of the sampling time t1, the number of revolution of the motor 3 is varied for a sampling time t2 newly set.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for an air conditioner, and more particularly to control of the rotation speed of an indoor blower.

[0002]

2. Description of the Related Art Conventionally, in the case of controlling the operation of an indoor blower by phase control, a position detecting element composed of a Hall IC or the like is provided in a blower motor, and the number of revolutions of the blower motor is detected and pulsed to control the indoor side. , The pulse is counted every predetermined sampling time, the difference from the preset target rotation speed is obtained, and the applied voltage is changed by phase control to correct and control the rotation speed of the blower motor. ing. However, the number of revolutions of the blower motor varies depending on the air-conditioning load and the load condition of the suction port, the outlet, etc., so frequent sampling is required, but from the difference between the number of revolutions obtained by sampling and the target number of revolutions. , It takes some time to change the rotation speed of the blower motor by changing the applied voltage by the phase control, and especially when the rotation speed is lowered, the rotation speed decreases rapidly because the blower motor does not have a brake mechanism. However, depending on how the sampling time is set, the rotation speed of the blower motor hardly changes, and correction control that further lowers the applied voltage is performed until the next sampling time, resulting in a situation where the target rotation speed is lowered and so on. However, there is a problem that the target rotation speed cannot be quickly followed. FIG. 4 shows the change in the rotation speed and the sampling time when the indoor control unit issues an instruction to increase the air flow.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art.
It is an object of the present invention to provide a control device for an air conditioner that can control the rotation speed of a blower motor so as to quickly follow a preset target rotation speed.

[0004]

In order to achieve the above object, a rotation speed detecting means for detecting the rotation speed of an indoor blower at every predetermined sampling time, and a first speed change rate for calculating the rotation speed. Predetermined sampling based on a calculation means, a second calculation means for calculating a difference between the detected rotation speed and a preset target rotation speed, and a difference between the temporal change rate of the predetermined rotation speed and the target rotation speed. A memory having a table in which the time is set is stored, and the sampling time is read from the memory and set by the output of these calculating means. In addition, the sampling time is set long when the difference with the target speed is large and the temporal change rate of the rotational speed is low, and set short when the difference with the target rotational speed is small and the temporal change rate of the rotational speed is high. I decided to do it.

[0005]

According to the above construction, the rotational speed of the indoor blower is detected, the temporal change rate of the detected rotational speed is calculated, and the difference between the detected rotational speed and the preset target rotational speed is calculated. When the difference from the target rotation speed is large and the time change rate of the rotation speed is low, the sampling time of the rotation speed detection means is lengthened, and when the difference from the target rotation speed is small and the time change rate of the rotation speed is high. By controlling the sampling time of the rotation speed detection means to be short, the indoor blower can be controlled so that the detected rotation speed quickly follows the target rotation speed without exceeding the target rotation speed.

[0006]

Embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a block diagram schematically showing the rotation speed control of the indoor blower 3. 1 is a commercial power supply, 2 is a drive circuit for controlling the phase of the blower motor 3, 3 is a blower motor, and 4 is a Hall IC built in the blower motor. A rotation speed detection circuit 5 and the like are indoor control units that are supplied with power from the power supply circuit 6, and the indoor control unit 5 compares the detected target rotation speed with the preset target rotation speed. The rotational speed comparison circuit 7, the temporal change rate calculation circuit 9 for calculating the temporal change rate of the rotational speed from the detected rotational speed and the immediately preceding rotational speed, and the preset target rotational speed and detected rotational speed. A memory 8 for storing a table for setting a sampling time based on a temporal change rate of the difference and the rotational speed is provided, and the table of the memory 8 is searched from the outputs of the rotational speed comparison circuit 7 and the temporal change rate calculating circuit 9 to perform sampling. Time t is calculated and driving time And controls the rotational speed of the blower motor 3 via the 2.

FIG. 2 is a diagram showing the state of the rotation speed and the sampling time when the rotation speed of the blower motor 3 is brought close to the target rotation speed by the air volume change instruction from the indoor side control unit 5.
(A) shows the time when the number of revolutions increases, and (b) shows the time when the number of revolutions decreases. When the air volume change is instructed from the indoor side control unit 5, the rotation speed at that time is detected, and the rotation of the blower motor 3 according to the temporal change rate toward the target rotation speed during the preset sampling time t1. Change the number. At the same time, the temporal change rate of the rotational speed is calculated from the difference between the target rotational speed and the detected rotational speed at that time, the immediately preceding rotational speed and the detected rotational speed, and the table of the memory 8 is searched to set the sampling time t2. When the sampling time t1 has elapsed, similarly, the rotation speed at that time is detected, and during the set sampling time t1, the rotation speed of the blower motor 3 is changed according to the temporal change rate toward the target rotation speed, and so on. Repeatedly match the target speed. As shown in the figure, by increasing the sampling time as the target rotation speed is approached, the rotation speed of the blower motor 3 gradually increases, so that the target rotation speed is exceeded or an unstable increase / decrease occurs. Repetition can be prevented.

FIG. 3 is a flow chart showing the details of the present invention. When the indoor side control unit 5 gives an instruction to change the air volume (2
1), the sampling time t1 is set (22), the rotation speed of the indoor blower is changed according to the temporal change rate of the rotation speed, and when the sampling time t1 has elapsed (23), the rotation speed R of the indoor blower is detected. (24) If the target rotation speed does not match (25), the difference from the target rotation speed and the temporal change rate ΔR
Is calculated (26) and the table in the memory 8 is searched (2
7) Then, the sampling time t2 is set (28), and the sampling time t2 is used instead of the sampling time t1 and the process is repeated until the target rotational speed is matched (29).

As described above, according to the present invention, the sampling time of the rotational speed is set from the difference between the temporal change rate of the rotational speed detected by the indoor blower and the target rotational speed, and every set sampling time is set. The target rotation speed is quickly tracked by detecting the rotation speed and changing the rotation speed by phase control.

[Brief description of drawings]

FIG. 1 is a block diagram showing an outline of rotation speed control of an indoor blower 3.

FIG. 2 is a diagram showing a state of a rotation speed and a sampling time when the rotation speed of a blower motor 3 approaches a target rotation speed.

FIG. 3 is a flow chart showing details of the present invention.

FIG. 4 is a diagram showing a state of conventional rotation speed and sampling time.

[Explanation of symbols]

 1 Commercial power supply 2 Drive circuit 3 Blower motor 4 Rotation speed detection circuit 5 Indoor side control unit 6 Power supply circuit 7 Rotation speed comparison circuit 8 Memory 9 Temporal change rate calculation circuit

Claims (2)

[Claims] 1. A rotation speed detection means for detecting the rotation speed of an indoor blower at every predetermined sampling time, a first calculation means for calculating a temporal change rate of the rotation speed, a detected rotation speed and a preset setting. Second calculation means for calculating a difference from the target rotational speed, and memory for storing a table in which a predetermined sampling time is set based on a difference between the temporal change rate of the preliminary rotational speed and the target rotational speed, An air conditioner controller, wherein the sampling time is read out from the memory and set by the output of these arithmetic means. 2. The sampling time is set long when the difference from the target rotation speed is large and the time change rate of the rotation speed is low, and the difference from the target rotation speed is small and the time change rate of the rotation speed is high. The control device for an air conditioner according to claim 1, wherein the control device is set to be short in some cases.