JP3654930B2 - Inverter device - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to an inverter device for performing variable speed control of an electric motor.
[0002]
[Prior art]
In the conventional inverter device, an input terminal for inputting an operation command or the like from the outside and an output terminal for outputting the operation status to the outside are arbitrarily selected from a plurality of functions for each terminal by fixing, for example, 8 input terminals and 4 output terminals. Had a means to assign functions.
[0003]
[Problems to be solved by the invention]
In the above inverter device, the functions to be allocated are abundant, but only a part of the functions can be used because of the limited number of terminals. In actual applications, in most cases, a logical operation is performed on a specific operation state and an external signal to obtain an operation command or the like, and an external control device for a programmable controller is required.
[0004]
The present invention has been made in view of the above problems, and its purpose is to use more functions that can be assigned to input / output terminals than the actual number of terminals, and to control a programmable controller or the like externally in actual applications. It is an object of the present invention to provide an inverter device that can perform a logical operation of a specific operation situation and an external signal to obtain an operation command without requiring an apparatus.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, in the present invention, a control circuit unit for controlling an inverter circuit for driving an electric motor, a switch unit for setting control condition data, data on conditions set by the switch unit, and current data A setting display unit comprising a display unit for displaying the operation status, at least one input terminal for inputting an operation command from the outside, at least one virtual input terminal not connected to the outside, and the operation status externally a plurality of output terminals for outputting, in an inverter apparatus having a plurality of output terminals of the virtual that is not connected to the outside, have a firm signal on terminal to one of the virtual input terminals, a plurality of functions to a plurality of input terminals A means for arbitrarily assigning functions, a means for arbitrarily assigning functions from a plurality of functions to a plurality of output terminals, and an external input / output terminal and an internal virtual terminal. It comprises a means for performing a logic operation, a means for allocating an operation result on any terminal in the meaning of the terminal.
[0006]
[Action]
The inverter device includes a current setting data, and the state of the input terminal by the signal from the outside, a state of the functions assigned to the result performs logical operation set in advance from the state of the virtual input terminals, the operation in accordance with the signal Execute and output the status of the function assigned to the output terminal or virtual output terminal to the terminal. The function assigned to the virtual input terminal of the constant signal on is always the signal on.
[0007]
【Example】
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
First, the overall configuration will be described with reference to FIG. The inverter circuit 1 includes power-side terminals 2, 3 and 4 and load-side terminals 5, 6 and 7. A three-phase AC power supply 8 is connected to the power-side terminals 2, 3 and 4, and the load-side terminal 5 , 6 and 7 are connected to an electric motor, for example, a three-phase induction motor 9. The inverter circuit 1 includes a DC power supply circuit 10. This DC power supply circuit 10 includes a full-wave rectifier circuit 11 having an AC input terminal connected to the power supply side terminals 2, 3, 4, and a smoothing capacitor 12 connected between the DC output terminals of the full-wave rectifier circuit 11. DC buses 13 and 14 are connected to both terminals of the smoothing capacitor 12.
[0008]
Further, between the DC buses 13 and 14, an inverter main circuit 21 formed by connecting transistors 15 to 20 as six switching elements in a three-phase bridge is connected, and the emitters of the transistors 15 to 17 are connected to the load side terminals 5 and 6. , 7. The six output terminals of the base drive circuit 22 are connected to the bases of the respective transistors 15 to 20 of the inverter main circuit 21. The inverter circuit 1 includes a control power supply circuit 23 whose input terminals are connected to the DC buses 13 and 14 so as to output a DC constant voltage control power supply between the output terminals. In the control power supply circuit 23 in this case, Vcc represents the control power supply voltage, and E represents the ground potential.
[0009]
The control circuit unit 24 includes a Mycolo computer (hereinafter abbreviated as CPU) 25. The CPU 25 has a built-in RAM 25a as a memory, and an input / output port is connected to a memory such as a rewritable nonvolatile memory 26. This is the non-volatile memory 26 the operating mode and the control condition data of a number of control items for example 350 entries are stored. The output port of the CPU 25 is connected to the base drive circuit 22 and controls the switching of the transistors 15 to 20 as switching elements to control the rotation of the induction motor 9. All the control circuit units 24 are managed by the CPU 25 and controlled according to the data in the built-in RAM 25a. Control condition data in the built RAM25a is stored in writable non-volatile memory 26 for storing the current setting data is transferred to the internal RAM25a during initialization.
[0010]
The control circuit unit 24 further includes a power supply monitoring circuit 29. The power supply monitoring circuit 29 has an input terminal connected to the output terminal of the control power supply circuit 23 and an output terminal connected to the input port of the CPU 25 until the control power supply voltage Vcc from the control power supply circuit 23 reaches a set level. Is configured to reset the CPU 25 to a reset (power-on reset) state. The control circuit unit 24 includes a terminal block 30. The terminal block 30 has a plurality of terminals such as 8 terminals connected to the input port of the CPU 25 via the buffer 27, and a plurality of terminals such as 4 terminals connected to the output port of the CPU 25 via the buffer 28. The plurality of terminals are connected to an external controller (not shown).
[0011]
The panel (setting operation unit) 31 includes a key matrix circuit 32 for setting operation, and these input and output terminals are connected to the input and output ports of the CPU 25. Further, an LED 33 for data and operation status display is provided, and these are connected to an output port of the CPU 25 via driver circuits 34 and 35.
[0012]
The operation of the inverter device configured as described above will be described.
First, when the three-phase AC power supply AC of the apparatus is turned on and the DC power supply Vcc is supplied from the control power supply circuit 23 to the control circuit unit 24, the CPU 25 starts the operation by the built-in program, and first clears the data in the built-in RAM 25a once. Measure. After this initialization, it reads the control condition data stored in the nonvolatile memory 26, and writes to the internal RAM25a. The CPU 25 performs a predetermined logical operation from the control condition data of the built-in RAM 25a, the state of the input terminal by an external signal, and the state of the virtual input terminal, and the operation is performed according to the signal as the assigned function state. Execute and output the status of the function assigned to the output terminal or virtual output terminal to the terminal. The function assigned to the virtual input terminal of the always-on signal is always on.
[0013]
The input terminals are 20 external input terminals (IT0 to IT7) and 12 virtual input terminals (IT8 to IT19), and the output terminals are 4 external output terminals (OT0 to OT3) and 8 virtual output terminals (OT4 to OT4). There are a total of 12 terminals of OT11). 20 input terminals are arbitrarily selected and assigned from 52 functions shown in FIG. 2, and 12 output terminals are arbitrarily assigned from 64 functions shown in FIG. As standard, the external input terminal 8 and the external output terminal 4 are assigned as shown in FIG. 4, the virtual input terminal IT19 is always on, and the virtual terminals are all assigned without control.
[0014]
The logical operation function includes, for example, an AND function, an OR function, a NOT function, and a timer function, and examples of commands include AND, OR, NOT, and = commands. Arithmetic is performed and assigned to any terminal. The setting is performed on the panel 31, and arbitrary terminals (IT0 to IT19, OT0 to OT11) are selected, the NOT command is selected when inverting the signal as necessary, and the time is input when the timer function is added. Next, select an AND command or an OR command, select an arbitrary terminal (IT0 to IT19, OT0 to OT11) to perform the next operation, and similarly select the NOT command to invert the signal and attach a timer function. If you enter a time. This is repeated as many times as necessary, and the result is assigned to the selected terminal after selecting the command. Similarly, the NOT command is selected when inverting the signal, and the time is input when the timer function is added.
[0015]
The virtual input terminal IT19 for always-on signal will be described. Here, the ST function is an operation preparation completion signal. When the ST function is always used as the signal on, the ST function can be assigned to the IT 19 so that the standard external input terminal IT7 can be assigned to any other function. . Similarly, when operation is stopped only by forward rotation and the operation is stopped by the frequency command value, the external input terminals ITO and IT5 of the standard setting are assigned to any other function by assigning the F (forward operation) function to IT19. It becomes possible.
[0016]
Next, the virtual terminal and the logical operation function will be described. For example, there is a case where high speed operation is performed at light load in an elevator inverter. Usually, it operates at 60 Hz, and at a light load, it operates at a high speed of 120 Hz. At this time, a current value is detected as a load detection, and when the current value is smaller than a preset current value for a certain period, the operation is switched to high speed operation. In a conventional inverter device, a signal is output from the output terminal when the current value is lower than a preset current value, an external programmable controller or the like reads the signal, measures the time, and switches the frequency command value to the inverter device, and two external devices An input terminal and one external output terminal were used. In the inverter device of the present embodiment, SSI (multi-speed operation 1) is selected for IT1 of the external input terminal, SS2 (other speed operation 2) is selected for IT9 of the virtual input terminal, and an undercurrent alarm is generated for OT4 of the virtual output terminal. Then, (IT1) AND (OT4 timer setting) = (IT9) is set as the logical operation, and the command value is set to 60 Hz when the SSI signal is on, and the command value is set to 120 Hz when both the SSI signal and the SS2 signal are on. By setting in this way, the inverter device itself checks the level of the current value by simply inputting an SSI signal from the outside, measures the time, and switches to high speed operation.
[0017]
According to the present embodiment, a plurality of input terminals for inputting a driving command from the outside, a plurality of virtual input terminals not connected to the outside, a plurality of output terminals outputting the driving status to the outside, and a virtual not connected to the outside In the inverter apparatus having a plurality of output terminals, a means for allocating a function arbitrarily from a plurality of functions to a plurality of input terminals, having a signal on terminal at one of the virtual input terminals, and a plurality of outputs to the plurality of output terminals It is necessary as an input signal because it has means to assign functions arbitrarily from functions, but the function to give always-on signal input becomes effective for limited external input terminals by assigning it to always-on virtual input terminals Can be used.
[0018]
Furthermore, according to the present embodiment, since a means for performing a logical operation on an external input / output terminal and an internal virtual terminal and a means for assigning an operation result to an arbitrary terminal are provided, a signal indicating an operation status is provided. Application control can be performed without assigning to the external output terminal by performing logical operation with the input terminal instead of the external output terminal, performing logical operation with the input terminal, and setting the result to the virtual input terminal and assigning the function to the virtual input terminal. It is possible to use limited external output terminals effectively. In addition, since it has a logic operation function and timer function, application control can be realized without the need for an external programmable controller when an external programmable controller is used for simple logic operations and timer functions. It becomes.
[0019]
(Other examples)
As another embodiment, the virtual input terminal and the virtual output terminal are both internal terminals, the function of the internal terminal can be arbitrarily selected from the input terminal function and the output terminal function, and the logical command is AND, OR. There are inverter devices that use other commands instead.
[0020]
【The invention's effect】
As described above, in the present invention, the inverter device for driving the electric motor has a constant signal on terminal as one of the virtual input terminals, and assigns a function arbitrarily from a plurality of functions to a plurality of input terminals, A means for arbitrarily assigning a function from a plurality of functions to an output terminal, a means for performing a logical operation on an external input / output terminal and an internal virtual terminal, and a means for assigning an operation result to an arbitrary terminal are provided. Therefore, more functions than the actual number of terminals can be used. Moreover, in an actual application, it is possible to provide an inverter device that can perform a logical operation of a specific operation state and an external signal to obtain an operation command without requiring an external control device such as a programmable controller. .
[Brief description of drawings]
FIG. 1 is a circuit configuration diagram of an embodiment of the present invention;
FIG. 2 is a diagram showing input terminal selection;
FIG. 3 is a diagram showing an output terminal function;
FIG. 4 is a diagram showing standard settings of input / output terminals.
[Explanation of symbols]
1 ... Inverter circuit, 9 ... Electric motor,
23 ... Control power supply circuit, 24 ... Control circuit section,
25 ... Microcomputer (CPU), 25a ... Built-in RAM,
26 ... Read / write nonvolatile memory,
29 ... Power supply monitoring circuit, 31 ... Panel (setting operation section),
IT0 to IT7 ... external input terminals,
IT8 to IT19: virtual input terminal,
OT0 to OT3 ... external output terminal terminals,
OT4 to OT11: Virtual output terminal terminals.

Claims (2)

A setting display comprising a control circuit unit for controlling an inverter circuit for driving an electric motor, a switch unit for setting control condition data, a condition data set by the switch unit, and a display unit for displaying a current operation status Unit, at least one or more input terminals for inputting operation commands from the outside, at least one or more virtual input terminals that are not connected to the outside, a plurality of output terminals for outputting the operation status to the outside, and connected to the outside In an inverter device with a plurality of virtual output terminals that are not, comprising: means for arbitrarily assigning functions from a plurality of functions to a plurality of input terminals; and means for arbitrarily assigning functions from a plurality of functions to a plurality of output terminals; One of the virtual input terminals is a signal on terminal at all times. 2. The inverter apparatus according to claim 1, further comprising means for performing a logical operation on an arbitrary terminal of an external input / output terminal and an internal virtual terminal, and means for assigning an operation result to the arbitrary terminal. .

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