JP3237393B2 - Operation and display of power converter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an operation / display of a power converter such as an inverter for driving a motor at a variable speed.

[0002]

2. Description of the Related Art FIG. 5 shows an example of a configuration of a power conversion device having a built-in operation / display unit. In this figure, a power converter 1 is composed of an operation / display 2, a power converter control circuit 3, and a power converter 4, and a power supply 5, for example, a commercial power is supplied to the power converter control circuit 3 and a power semiconductor switch. The power is converted into desired power by a power converter 4 composed of elements and the like, and is supplied to a load 6.

The operation / display unit 2 includes a panel unit 10 and a control unit 2.
The panel unit 10 includes a 7-segment LED 11 that displays the operating state of the power converter 1 in characters.
And a liquid crystal display 12 for displaying text and the like, and a plurality of key switches 13 for inputting control operation parameters and operation / stop commands.
Operating means 21 for operating and stopping the operation of the power conversion device 1 and a seven-segment LED 11
Control means 22 for displaying on the LCD and the liquid crystal display 12
And parameter setting means 23 for setting and changing various parameters required for the control operation of the power conversion device 1 instructed by the key switch 13 and the like. The control circuit 3 performs a control operation.

[0004]

In the above-mentioned conventional power converter, a liquid crystal display without a normal backlight is used as a liquid crystal display for displaying the operating state of the power converter in text or the like. In this case, since the displayed characters are not clear, there is a problem that it takes time to confirm the displayed contents. In addition, as a countermeasure for the above, a liquid crystal display with a backlight is used to sharpen displayed characters, but usually, when the power converter is charged, the backlight is always turned on. Since the backlight is turned on, as shown in FIG. 6, there is a problem that the brightness of the backlight decreases with the passage of the lighting time, and the display becomes unclear after long use.

[0005] It is an object of the present invention to provide an operation / display device for a power conversion device that solves the above-mentioned problems.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention relates to a power converter for supplying a desired power to a load by a power converter comprising a power semiconductor switch element or the like. Operating means for operating the operation and stop of the device, display control means for displaying an operation state and the like of the power converter, setting of various parameters necessary for control operation of the power converter,
A parameter setting means for changing, a liquid crystal display with a backlight for displaying by an output of the display control means, and a plurality of key switches for inputting to the operation means and the parameter setting means, as follows: Shall be configured. (1) The parameter input by the key switch is provided with a parameter for instructing turning on and off of the backlight of the liquid crystal display, and based on the instruction of the parameter, turning on and off of the backlight of the liquid crystal display. Control. (2) The backlight of the liquid crystal display is turned on when any one of the key switches for performing operations such as operation and stop, and setting and changing of various parameters is input by the display control means, and the key switch The backlight is turned off when any one of them has not been input for a preset period. (3) In the above (1) or (2), the backlight of the liquid crystal display is turned on by the display control means if the backlight is on when an abnormality occurs in the power converter. If the backlight is off, the backlight is turned on.

[0007]

In the present invention, a backlit liquid crystal display for clearing the displayed characters is used for the liquid crystal display for displaying the operation state and the like of the power conversion device in text, etc. When the luminance of the backlight decreases, the backlight is turned off when the backlight is unnecessary, so that the progress of the luminance decrease can be suppressed.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 5 shows an example of the configuration of a power conversion device having a built-in operation / display unit, in which a display control means 22a using a liquid crystal display unit 12a with a backlight is used to turn on and off the backlight. FIG. 5 shows the control operation of the present invention.
This will be described with reference to the flowchart shown below.

FIG. 1 is a flowchart showing a first embodiment of the present invention. In FIG. 1, the key switch 13
Then, each time the key switch is pressed, the backlight of the backlit liquid crystal display 12a is turned on / off.
A light-off key is provided, and it is checked whether the light-on / light-off key has been pressed (step S11). If the light-on / light-off key has been pressed (step S11, branch Y), it is checked whether the backlight is currently turned on (step S12). If the backlight is on (step S12, branch Y), the backlight is turned off (step S13). If the backlight is off (step S12, branch N), the backlight is turned on (step S14).

FIG. 2 is a flowchart showing a second embodiment of the present invention. In FIG. 2, the key switch 13
A parameter for turning on and off the backlight of the liquid crystal display with backlight 12a is provided as a parameter of the parameter setting means 23 input from the controller. If the parameter is "1", the parameter is turned on; (Step S21), if the parameter is "1" (step S21, branch Y), the backlight is turned on (step S22), and if the parameter is "0" (step S21, branch N). Then, the backlight is turned off (step S23).

FIG. 3 is a flowchart showing a third embodiment of the present invention. In FIG. 3, it is checked whether any one of the plurality of key switches 13 has been pressed (step S31), and if it has not been pressed (step S3).
(1, branch N), the timer (not shown) provided in the display control means 22a is incremented (step S32), and it is checked whether or not the timer has counted a predetermined time (step S33). If the time has elapsed (step S33, branch Y), the backlight of the liquid crystal display with backlight 12a is turned off (step S34). When the key is pressed in step S31 (step S31, branch Y), the timer is reset (step S35), and the liquid crystal display with backlight 1 is reset.
The backlight of 2a is turned on (step S3
6).

FIG. 4 is a flowchart showing a fourth embodiment of the present invention. In FIG. 4, it is checked whether or not an abnormality has occurred in the power converter 1 (step S41), and when an abnormality has occurred (step S41,
(Branch Y9), it is checked whether or not the backlight of the liquid crystal display with backlight 12a is turned on (step S4).
2) If not turned on (step S42, branch N), the backlight is turned on (step S43).

Although the first to fourth embodiments have been described above, an embodiment in which the first to fourth embodiments are appropriately combined,
For example, an embodiment in which the first embodiment and the fourth embodiment are combined can be naturally implemented. Further, it is also possible to detect the brightness around the place where the power conversion device 1 is installed, and to control the turning on / off of the backlight of the liquid crystal display with backlight 12a based on the detected signal.

[0014]

By controlling the turning on and off of the backlight of a liquid crystal display with a backlight according to preset conditions, the backlight is turned on only when necessary, thereby enabling the display content of the screen of the liquid crystal display to be changed. Confirmation is facilitated, and a decrease in the brightness of the backlight can be suppressed.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a first embodiment of the present invention.

FIG. 2 is a flowchart showing a second embodiment of the present invention;

FIG. 3 is a flowchart showing a third embodiment of the present invention.

FIG. 4 is a flowchart showing a fourth embodiment of the present invention.

FIG. 5 is a configuration example diagram of a power converter.

FIG. 6 is a characteristic diagram of a backlight of a liquid crystal display with a backlight.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Power converter, 2 ... Operation / display, 3 ... Power converter control circuit, 4 ... Power converter, 5 ... Power supply, 6 ... Load, 10
... Panel section, 11 ... 7-section LED, 12 ... Liquid crystal display, 12a ... Liquid crystal display with backlight, 13 ... Key switch, 20 ... Control part, 21 ... Operation means, 22,2
2a: display control means, 23: parameter setting means.

Claims (3)

(57) [Claims] 1. A power converter for supplying a desired power to a load by a power converter composed of a power semiconductor switch element or the like, comprising: operating means for operating the power converter, starting and stopping the power converter, and the like. Display control means for displaying an operation state and the like of the power conversion device; parameter setting means for setting and changing various parameters necessary for the control operation of the power conversion device; display by an output of the display control means A backlight-equipped liquid crystal display, and a plurality of key switches input to the operation means and the parameter setting means, wherein the parameters input by the key switches include:
A parameter for instructing turning on and off of the backlight of the liquid crystal display is provided, and turning on and off of the backlight of the liquid crystal display is controlled based on the instruction of the parameter. display. 2. A power converter for supplying a desired power to a load by a power converter composed of a power semiconductor switch element and the like, comprising: operating means for operating the power converter, starting and stopping the power converter, and the like. A display control unit for displaying an operation state of the power conversion device, a parameter setting unit for setting and changing various parameters necessary for a control operation of the power conversion device, and a display by an output of the display control unit A backlight-equipped liquid crystal display, and a plurality of key switches for inputting to the operation means and the parameter setting means, wherein the display control means performs operations such as operation and stop, and operations for setting and changing various parameters. When any of the key switches is input, the backlight of the liquid crystal display is turned on, and any of the key switches is set in advance. Operation and display unit of the power conversion apparatus characterized by turning off the backlight when not duration input. 3. The operation / display of the power converter according to claim 1, wherein the backlight of the liquid crystal display is turned on by the display control means when an abnormality occurs in the power converter. An operation / display unit for a power conversion device, characterized in that if the light is on, the lighting is continued, and if the backlight is off, the light is turned on.