JP2606228Y2 - Inverter device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inverter device for driving an AC motor at a variable speed.

[0002]

2. Description of the Related Art For example, a general-purpose inverter device used for driving an induction motor for an industrial machine at a variable speed is required to be able to change its operation specifications on a user side. For this reason, the conventional general-purpose inverter device includes a parameter setting unit for changing and setting parameters such as a starting frequency, an acceleration / deceleration time, and a voltage boost amount, and a display unit for displaying the set parameter data. Configuration is adopted.

[0003] Among various types of parameters prepared in a general-purpose inverter device, there is a type in which a change setting operation is performed while an induction motor is actually driven. Specifically, for example, when changing parameters such as the acceleration / deceleration time and the voltage boost amount, the parameter data to be changed is raised or lowered while the induction motor is actually driven, and the associated parameter data is changed. The parameter is adjusted to an optimum state while monitoring the change state of the parameter by the display means.

[0004]

[Problem to be Solved by the Invention] When performing a parameter change operation while the induction motor is actually driven as described above, once the change operation is started, the parameter adjustment is not as expected. Instead, the parameter data before the change operation is often better than the parameter data after the change operation. In such a case, in the conventional inverter device, even if it is attempted to return to the parameter data before the change, it is difficult to return to the original state because the parameter data has already been changed. There is. In addition, in order to deal with such a problem, it is necessary to take time to write down the parameter data before the change, and as a result, operability and workability when changing and setting the parameter are inferior. It was under circumstances.

The present invention has been made in view of the above circumstances, and has as its object to easily and reliably return to the parameter data before the change even after the parameter data for determining the operating specifications of the AC motor is once changed. It is therefore an object of the present invention to provide an inverter device capable of improving operability and workability when changing parameters.

[0006]

According to the present invention, in order to achieve the above object, an inverter device for controlling an AC motor at a variable speed, in particular, changing a plurality of parameters for determining an operation specification of the AC motor. In an inverter device including a parameter setting unit that can be set and a display unit that displays setting parameter data by the parameter setting unit, current parameter data is stored when a parameter changing operation is performed by the parameter setting unit. A storage means is provided, and a notification means for performing a notification operation when the parameter data being changed coincides with the parameter data stored in the storage means at the time of the parameter changing operation is provided.

In this case, the notification means may be configured to perform the notification operation by blinking the parameter data displayed by the display means.

[0008]

When changing a parameter while actually driving the AC motor, when the change operation is performed, the parameter data before the change is stored in the storage means. When the parameter data being changed matches the parameter data stored in the storage unit as described above during the parameter change operation as described above, the notification unit performs the notification operation. Therefore, when performing the parameter change operation while driving the AC motor, once the change operation is started, if the change operation is stopped when the above-described notification operation is performed, the change operation can be performed before the start of the change operation. Can be easily and reliably returned to the parameter data.

In the case where the above-described notification operation is performed by blinking the parameter data displayed by the display means, it is not necessary to add another component for the notification operation. This is advantageous in cost.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. That is, in FIG. 1, a PWM inverter unit 1 as an inverter device rectifies and smoothes the output of a three-phase AC power supply 2 through a rectifier circuit 3 and a smoothing capacitor 4, and converts the smoothed DC output into AC power by an inverter circuit unit 5. The conversion output controls the three-phase induction motor 6 as an AC motor at a variable speed. In this case, the inverter circuit section 5 includes, for example, six IGBTs 5a connected in a three-phase bridge and a flywheel diode 5b connected to each of the IGBTs 5a. It is configured to generate a three-phase AC output of a variable frequency and a variable voltage in response to being turned off.

The PWM inverter unit 1 is provided with a parameter unit 8, a control unit 9, and a power supply circuit 10 constituting a control power supply, in addition to the inverter circuit unit 5, the drive circuit 7, and the like as described above. .

The parameter unit 8 is provided with an operation panel 11 which is exposed on the surface of the PWM inverter unit 1. The operation panel 11 has a key switch group 12 as parameter setting means, and a display. A display panel 13 as means is provided.

The parameter unit 8 includes various command signals such as operation start and stop, operation frequency (corresponding to the target rotation speed of the induction motor 6), start frequency, acceleration / deceleration time, In addition to signals for specifying various operation parameter data such as voltage boost amount and protection characteristics, a parameter specification signal for specifying the parameter to be changed, a change start command signal for instructing the start of the parameter change, and a parameter change stop , A command signal for increasing the parameter data, and a command signal for decreasing the parameter data. These signals are given to the control unit 9. Particularly, in this case, the key switch group 12 is provided with an increment key 12a and a decrement key 12b as keys for generating the increase command signal and the decrease command signal throughout the ON operation period. The display panel 13 is configured to display character and numeric data by, for example, a liquid crystal display panel.

The control unit 9 includes a PWM control circuit 14 for performing PWM control of the inverter circuit unit 5 through the drive circuit 7, an overvoltage protection operation based on the terminal voltage of the smoothing capacitor 4, and a load detected by the current transformer 15. In addition to a protection circuit 16 that performs an overcurrent protection operation based on a current, an operation circuit 17 and a storage circuit 18 corresponding to the notification unit and the storage unit according to the present invention are provided.
Note that the control unit 9 actually includes a microcomputer.

The operation circuit 17 calculates an output frequency, an output voltage, a protection characteristic and the like based on various command signals and parameter data given from the parameter unit 8, and based on the calculation results, the PWM control circuit 14 and the protection circuit 16 And the control described below in connection with the parameter changing operation.

That is, the operating circuit 17 receives from the parameter unit 8 a parameter designation signal for designating a parameter to be changed and a change start command signal for instructing a start of parameter change in a drive state of the AC motor 6. Sometimes, the configuration is such that a parameter change program as shown in FIG. 2 is executed.

In FIG. 2, in the parameter change program, first, the currently set value of the designated parameter (hereinafter referred to as parameter data ΔP).
Is displayed on the display panel 13 (step S1), and the display parameter data ΔP is updated and stored in the storage circuit 18 as the original parameter data ΔPa (step S2). After the execution of the storage operation, a loop is formed to wait until any of the increase command signal, the decrease command signal, and the change stop command signal is input (steps S3 to S5).

When the increase command signal is input ("YES" in step S3), that is, the increment key 12a
Is turned on, the parameter data ΔP is incremented by a unit amount (step S6), and switching is performed so that the PWM control of the inverter circuit unit 5 through the PWM control circuit 14 is performed based on the parameter data ΔP after the increment (step S6). S7), and display panel 1
3 is changed to a new one (step S8).

Next, it is determined whether or not the parameter data ΔP displayed on the display panel 13 matches the original parameter data ΔPa (corresponding to the parameter data ΔP before the change) stored in the storage circuit 18 (step). S
9).

If the two parameter data ΔP and ΔPa match, a blinking command for the parameter data ΔP displayed on the display panel 13 is generated (step S1).
0), and thereafter, step S11 of waiting for a predetermined short time τ is executed, and the process returns to step S3. On the other hand, the parameter data ΔP and the original parameter data ΔP
If a does not match, steps S12 and S11 for generating a command to stop the blinking of the parameter data ΔP displayed on the display panel 13 are executed, and the process returns to step S3.

When a decrease command signal is input ("YES" in step S4), that is, when the decrement key 1
2b is turned on, the parameter data ΔP
Is decremented by a unit amount (step S13), and PW
Switching is performed so that the PWM control of the inverter circuit unit 5 through the M control circuit 14 is performed based on the decremented parameter data ΔP (step S14), and the parameter data ΔP displayed on the display panel 13 is changed to a new one. (Step S15). Thereafter, the control after the determination step S9 is executed in the same manner as described above.

Further, when the change stop command signal is input ("YES" in step S5), the execution of the parameter change program is stopped as it is, and the parameter data at the time of input of the change stop command signal is thereby stopped. ΔP will be set as a new parameter.

In short, the parameter change operation using the above-described parameter change program is performed while the AC motor 6 is actually driven. When such a change operation is performed, the change before the change is performed. The parameter data ΔP is stored in the storage circuit 18 as the original parameter data ΔPa
And the changed parameter data Δ
P are sequentially displayed on the display panel 13. When the parameter data ΔP changed according to the parameter changing operation through the key switch group 12 matches the original parameter data ΔPa after being increased or decreased once, the operation circuit 17 is displayed on the display panel 13. By making the parameter data ΔP blink, the notification operation according to the present invention is performed.

Therefore, after the parameter change operation is started once while driving the induction motor 6, if the parameter change operation is stopped when the above-described notification operation is performed, the original parameter before the start of the change operation is obtained. Data ΔPa
Will be returned to. As a result, the induction motor 6
After the parameter change operation is started once in a state where is driven, the parameter adjustment is not as expected, and the original parameter data ΔPa before performing the change operation is better than the parameter data ΔP after the change operation. If the parameter data is changed, it is possible to easily and reliably return to the original parameter data ΔPa. The workability and workability are improved.

Further, according to the configuration of the above-described embodiment, the notification operation that the parameter data .DELTA.P being changed matches the original parameter data .DELTA.Pa before the change is performed by using the originally existing display panel 13. In addition, there is an advantage that the number of parts is not increased and the cost becomes advantageous.

The notifying operation when the parameter data being changed coincides with the parameter data before the change during the parameter changing operation is not limited to the blinking of the display data by the display panel 13 as in the above-described embodiment, but may be a buzzer. It is good also as composition which performs by ringing of etc.

[0027]

As is apparent from the above description, according to the first aspect of the present invention, it is possible to change the parameters for determining the operating specifications of the AC motor while actually driving the AC motor. Even after the parameter data has been changed once, the parameter data can be easily and reliably returned to the parameter data before the change based on the notification operation by the notification means, so that the operability and workability when changing the parameter are improved. It has an excellent effect that the improvement of the quality can be realized.

According to the second aspect of the present invention, since the above-described notification operation is performed using the display means which is originally present, another component is newly added in performing the notification operation. This eliminates the need and is advantageous in terms of cost.

[Brief description of the drawings]

FIG. 1 is a functional block diagram showing an electrical configuration of an embodiment of the present invention.

FIG. 2 is a flowchart for explaining control contents;

[Explanation of symbols]

In the drawing, 1 is a PWM inverter unit (inverter device), 2 is a three-phase AC power supply, 5 is an inverter circuit unit, 6 is a three-phase induction motor (AC motor), 8 is a parameter unit, 9 is a control unit, and 12 is a key. A switch group (parameter setting means), 13 indicates a display panel (display means), 17 indicates an operation circuit (notification means), and 18 indicates a storage circuit (storage means).

Claims (2)

(57) [Scope of request for utility model registration] 1. An AC motor for performing variable speed control, wherein parameter setting means for changing and setting a plurality of parameters for determining an operation specification of the AC motor, and setting parameter data by the parameter setting means are provided. in the inverter device provided with a display means for displaying the row parameter changing operation by said parameter setting means
When cormorants, storage means for storing the current parameter data, and a notification means for performing notification operation when the parameter data being changed at the time of change operation the parameter matches the parameter data stored in said storage means An inverter device characterized by being provided. 2. The inverter device according to claim 1, wherein the notifying unit is configured to perform the notifying operation by blinking the parameter data displayed by the display unit.