Power converter and method of controlling a power converter

Abstract

Provided is a power converter capable of easily performing the same input as an input from a digital input terminal. The power converter includes an input terminal for inputting an input signal in either an on or off state, a first operation key for accepting an operation, and a control section, wherein the control section performs a first process selected from a plurality of input process candidates by setting according to the input signal input to the input terminal, and in the case where the first operation key is pressed, the control section performs either a standard process set in advance or a second process selected from the plurality of input process candidates by setting according to a state at the time of pressing the first operation key.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a power converter and a control method of a power converter. BACKGROUND

[0002] A power converter is known which converts alternating current input from a commercial power source or the like and supplies alternating current of a different frequency to a load such as a motor. The power converter is provided with a digital input terminal. The power converter performs control such as starting or stopping operation or changing the output frequency by inputting a control signal from the digital input terminal.

[0003] Patent Document 1 discloses an inverter device (power converter) which can change functions for each input of an input device.

[0004] <RELATED ART DOCUMENTS>

[0005] <PATENT DOCUMENTS>

[0006] Patent Document 1: Japanese Patent Application Publication No. 2005-354778 SUMMARY

[0007] PROBLEMS TO BE SOLVED BY THE INVENTION

[0008] In order to use the digital input terminal of the power converter, a switch of an external device needs to be prepared. In addition, the switch of the external device needs to be wired to the digital input terminal.

[0009] The present disclosure provides a power converter which can easily perform the same input as from a digital input terminal.

[0010] MEANS FOR SOLVING THE PROBLEMS

[0011] According to one aspect of the present disclosure, a power converter includes an input terminal for inputting an input signal of either on or off, a first operation key for accepting an operation, and a control section, wherein the control section performs a first process selected from a plurality of input processing candidates by setting, according to the input signal input to the input terminal, and when the first operation key is pressed, the control section performs either a standard process set in advance or a second process selected from the plurality of input processing candidates by setting, according to a state at the time when the first operation key is pressed.

[0012] EFFECTS OF THE INVENTION

[0013] According to the power converter of the present disclosure, the same input as from a digital input terminal can be easily performed. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1is a block diagram of the power converter of the present embodiment.

[0015] Figure 2 is a front view of an operation section of the power converter of the present embodiment.

[0016] Figure 3 is a flowchart for explaining processing of a control section of the power converter of the present embodiment.

[0017] Symbol Explanation

[0018] 1 Power converter

[0019] 10 Power conversion section

[0020] 20 Operation section

[0021] 30 Control section

[0022] 50 Input terminal section

[0023] 60 Output terminal section

[0024] 217 Multifunction key

[0025] 225 Multi-display LED

[0026] TX1, TX2, TX3, TX4 Digital input terminal

[0027] TY1, TY2, TY3, TY4 Digital output terminal DETAILED DESCRIPTION

[0028] Hereinafter, each embodiment of the present application will be explained with reference to the drawings. Note that, regarding the description and the drawings according to each embodiment, the same symbol will be given to a constituent element having substantially the same or corresponding function configuration in order to omit repeated explanation. In addition, in order to facilitate understanding, the ratio of each part in the drawings will sometimes be different from the actual one.

[0029] <<Power converter 1>>

[0030] Figure 1 is a block diagram of the power converter 1 of the present embodiment. The power converter 1 converts, for example, three-phase alternating current supplied from a power supply 2 into direct current inside. Then, the power converter 1 converts the direct current into alternating current having a set frequency, and supplies power to a load 3 such as a motor.

[0031] The power converter 1 includes a power conversion section 10, an operation section 20, a control section 30, a power supply terminal section 40, an input terminal section 50, and an output terminal section 60.

[0032] <Power conversion section 10>

[0033] The power conversion section 10 internally converts the three-phase alternating current supplied from the power supply 2 into direct current. Then, the power conversion section 10 converts the converted direct current into alternating current having a predetermined frequency. Then, the power conversion section 10 supplies the power to the load 3.

[0034] The power supply 2 is a so-called commercial power supply. The power supply 2 supplies, for example, three-phase alternating current. The voltage of the power supplied from the power supply 2 is, for example, 200 V or 400 V. The frequency of the power supplied from the power supply 2 is, for example, 50 Hz or 60 Hz. Note that the voltage and the frequency shown above are examples, and other voltage or frequency can also be used.

[0035] Note that the power supply 2 is not limited to three-phase alternating current, and can be single-phase alternating current or two-phase alternating current, for example. In addition, the power supply 2 is not limited to alternating current, and can be direct current.

[0036] The power converter 1 is provided with power supply input terminals TL1, TL2, and TL3, and power supply output terminals TU, TV, and TW in the power supply terminal section 40. The power supplied from the power supply 2 is supplied to the power conversion section 10 of the power converter 1 via the power supply input terminals TL1, TL2, and TL3 of the power supply terminal section 40, respectively.

[0037] The power supplied from the power supply 2 to the power conversion section 10 is rectified and converted into direct current by a converter circuit composed of, for example, a diode bridge or the like inside the power conversion section 10. The converted direct current is converted into alternating current having a desired frequency by an inverter circuit composed of, for example, a switching element such as an IGBT (Insulated Gate Bipolar Transistor).

[0038] The alternating current converted and output by the power conversion section 10 is supplied to the load 3 via the power supply output terminals TU, TV, and TW of the power supply terminal section 40, respectively.

[0039] The load 3 is, for example, an electric motor such as a three-phase motor.

[0040] By converting the frequency of the power supplied from the power supply 2 by the power conversion section 10 of the power converter 1 and supplying it to the load 3, it is possible to control, for example, the rotational speed of the electric motor as the load 3 or the like.

[0041] <Operation Section 20>

[0042] The operation section 20 receives an operation from an operator to perform start or stop of the power converter 1 or change of a setting. Figure 2 is a front view of the operation section 20 of the power converter 1 of the present embodiment.

[0043] The operation section 20 has seven operation keys, six light emitting elements, and a seven-segment LED display of five digits on the touch panel 21.

[0044] [Operation keys]

[0045] The operation section 20 has a run key 211, a stop key 212, a program reset key 213, a function data key 214, an up key 215, a down key 216, and a multifunction key 217 as operation keys.

[0046] The run key 211 is a key that is pressed when starting the operation of the power converter 1. Specifically, when the run key 211 is pressed, the power converter 1 starts the operation. When the power converter 1 starts the operation, alternating current having a set frequency is supplied from the power supply output terminals TU, TV, and TW of the power supply terminal section 40 to the load 3. For example, in the case where the load 3 is a motor, the motor starts rotating. During the operation of the power converter 1, an operation LED 221 to be described later is lit.

[0047] The stop key 212 is a key that is pressed when stopping the operation of the power converter 1. Specifically, when the stop key 212 is pressed, the power converter 1 stops the operation. When the power converter 1 stops the operation, the supply of power from the power supply output terminals TU, TV, and TW of the power supply terminal section 40 to the load 3 is stopped. For example, in the case where the load 3 is a motor, the rotation of the motor is stopped. When the power converter 1 is stopped, the lit operation LED 221 is turned off.

[0048] The program reset key 213 is a key that is pressed when switching the operation mode.

[0049] As one example, the power converter 1 has three operation modes, namely, a run mode, a program mode, and an alarm mode. The run mode performs the setting of a frequency or an instruction value, and a run / stop instruction. The program mode is a mode for confirming a function setting or a device state. The alarm mode is a mode for displaying information of an alarm that occurs when an alarm occurs.

[0050] When the program reset key 213 is pressed in the run mode, the operation mode is switched to the program mode. When the program reset key 213 is pressed in the program mode, the operation mode is switched to the run mode. When the program reset key 213 is pressed after the alarm cause is resolved in the alarm mode, the operation mode is switched to the run mode.

[0051] The function data key 214 is a key that is pressed when confirmation of switching or selection of display is made. When the function data key 214 is pressed in the operation mode, the monitoring items of the running state, such as the output frequency, the output current, the output voltage, and the like are switched. When the function data key 214 is pressed in the program mode, the displayed data on the 7-segment LED display 230 is confirmed, for example. When the function data key 214 is pressed in the alarm mode, the display of the alarm information is switched.

[0052] The up key 215 and the down key 216 are keys that are pressed when selection of a set item or a displayed item or change of a displayed value on the 7-segment LED display 230 is made.

[0053] The multifunction key 217 is a key that has different functions depending on the state when the multifunction key 217 is pressed. For example, in the case where the multifunction key 217 is pressed for less than 1 second, movement of a cursor displayed on the 7-segment LED display 230 is made. Also, for example, in the case where the multifunction key 217 is pressed for 1 second or more, the control section 30 processes the input set.

[0054] [Light emitting element]

[0055] The operation section 20 has the operation LED 221, the unit LEDs 222, 223, and 224, the multiple display LED 225, and the keyboard control LED 226 as light emitting elements.

[0056] The operation LED 221 is an LED that is lit when the power converter 1 is operating, and is turned off when the power converter 1 is stopped.

[0057] The unit LEDs 222, 223, and 224 are used to indicate the physical quantity (monitoring item) and the unit of the value displayed on the 7-segment LED display 230 in the operation mode. Also, the unit LEDs 222, 223, and 224 are used to indicate that the operation mode is the program mode.

[0058] For example, when only the unit LED 222 is lit, it indicates that the monitoring item is "consumed power" and the unit is "kW". When only the unit LED 223 is lit, it indicates that the monitoring item is "output current" and the unit is "A". When only the unit LED 224 is lit, it indicates that the monitoring item is "output frequency" and the unit is "Hz".

[0059] Also, when the unit LED 222 and the unit LED 223 are lit and the unit LED 224 is turned off, it indicates that the monitoring item is "linear speed" and the unit is "m / min". When the unit LED 223 and the unit LED 224 are lit and the unit LED 222 is turned off, it indicates that the monitoring item is "motor rotation speed" or "load rotation speed" and the unit is "r / min".

[0060] Further, when the unit LED 222 and the unit LED 224 are lit and the unit LED 223 is turned off, it indicates that the operation mode is the program mode.

[0061] The multiple display LED 225 is an LED having different display functions according to the setting.

[0062] The keyboard control LED 226 indicates that the operation key 211 of the touch panel 21 is active.

[0063] [7-segment LED display]

[0064] The 7-segment LED display 230 is used to display a numerical value or a setting item.

[0065] [Control section 30]

[0066] The control section 30 controls the power converter 1. The control section 30 includes, for example, a central processing unit (CPU) and a storage device such as a memory, which are not shown. By reading out and executing a program stored in the storage device, a desired process is executed in the power converter 1.

[0067] The control section 30 receives inputs from the digital input terminals TX1, TX2, TX3, and TX4 of the input terminal section 50, respectively. The digital input terminals TX1, TX2, TX3, and TX4 are programmable general-purpose digital input terminals, respectively.

[0068] The digital input terminals TX1, TX2, TX3, and TX4 of the input terminal section 50 are used to input an arbitrary input signal of ON or OFF. The power converter 1 of the present embodiment determines whether conduction or non-conduction is established between each of the digital input terminals TX1, TX2, TX3, and TX4 and the input common terminal TxC. Also, the power converter 1 of the present embodiment determines whether the input signal from each of the digital input terminals TX1, TX2, TX3, and TX4 is ON or OFF, depending on whether conduction or non-conduction is established. For example, the power converter 1 determines that it is ON when conduction is established between the digital input terminal and the input common terminal, and determines that it is OFF when non-conduction is established.

[0069] The user can select the input process assigned to each of the digital input terminals TX1, TX2, TX3, and TX4 from among a plurality of input process candidates by setting. For example, the control section 30 can assign the functions of Table 1 to the digital input terminals TX1, TX2, TX3, and TX4, respectively. The process assigned to each of the digital input terminals TX1, TX2, TX3, and TX4 by the control section 30 is one example of the first process.

[0070] Note that the input signal in the on or off is not limited to the on or off signal described above, and can be, for example, a voltage signal, a current signal, a frequency signal, or the like.

[0071] [Table 1]

[0072] Functions settable in digital input terminals and multifunction keys Multi-stage frequency selection (0~1 stage) Multi-stage frequency selection (0~3 stage) Multi-stage frequency selection (0~7 stage) Multi-stage frequency selection (0~15 stage) Acceleration / deceleration selection (2 stage) Acceleration / deceleration selection (4 stage) Self-holding selection Idle operation command Alarm (abnormality) reset External alarm Micro-motion operation ···

[0073] The control section 30 outputs the output signal from the digital output terminals TY1, TY2, TY3, and TY4 of the output terminal section 60. The digital output terminals TY1, TY2, TY3, and TY4 are programmable general-purpose digital output terminals, respectively.

[0074] The digital output terminals TY1, TY2, TY3, and TY4 of the output terminal section 60 are used to output an arbitrary output signal in the on or off. The power converter 1 of the present embodiment outputs the output signal from each of the digital output terminals TY1, TY2, TY3, and TY4, depending on whether the on or off between each of the digital output terminals TY1, TY2, TY3, and TY4 and the output common terminal TYC. For example, the power converter 1 outputs the on when the on between the digital output terminal and the output common terminal, and outputs the off when the off.

[0075] In the power converter 1 of the present embodiment, the on or off between each of the digital output terminals TY1, TY2, TY3, and TY4 and the output common terminal TYC is switched by the switches SW1, SW2, SW3, and SW4, respectively.

[0076] The user can select the output processing respectively assigned to the digital output terminals TY1, TY2, TY3, and TY4 from among a plurality of output processing candidates by setting. For example, the control section 30 can assign the functions of Table 2 to the digital output terminals TY1, TY2, TY3, and TY4, respectively.

[0077] [Table 2]

[0078] Functions settable in output terminals and multi-display LEDs Operation period Frequency (speed) reaching Frequency (speed) detection Insufficient voltage stop period Torque polarity detection Inverter output restriction period Transient power failure recovery operation period ···

[0079] The digital output terminals TY1, TY2, TY3, and TY4 are connected to, for example, the external device 4, respectively. The external device 4 is, for example, a display LED, a programmable logic controller.

[0080] Further, for example, the control section 30 can assign the functions of Table 1 to the multifunction key 217. In addition, for example, the control section 30 can assign the functions of Table 2 to the multiple display LEDs 225. That is, the user can select the display processing assigned to the multiple display LEDs 225 from among a plurality of display processing candidates by setting. The multiple display LEDs 225 are one example of a display element. The processing displayed by the multiple display LEDs 225 is one example of a display processing.

[0081] Note that the output signal in the on or off is not limited to the on or off signal described above, and can be, for example, a voltage signal, a current signal, a frequency signal, or the like.

[0082] Next, the processing of the control section 30 when the multifunction key 217 is pressed, that is, the control method of the power converter 1 will be described. Figure 3 is a flowchart of the processing of the control section 30 of the power converter 1 of the present embodiment when the multifunction key 217 is pressed.

[0083] When the start processing is started, the control section 30 determines whether or not the multifunction key 217 is pressed (step S10). In the case where the multifunction key 217 is not pressed (NO in step S10), the control section 30 performs the processing of step S40.

[0084] In the case where the multifunction key 217 is pressed (YES in step S10), the control section 30 determines whether or not the multifunction key 217 is pressed for a predetermined time or more, for example, whether or not it is pressed for 1 second or more (long pressing) (step S20).

[0085] In the case where the multifunction key 217 is pressed for 1 second or more (long pressing) (YES in step S20), the control section 30 toggles the input signal between on and off with the multifunction key 217 with respect to the processing selected from among a plurality of input processing candidates by setting (step S30). That is, in step S30, the control section 30 performs the input processing selected from among a plurality of input processing candidates by setting. Then, the control section 30 performs the processing of step S40.

[0086] Note that in step S30, in the case where the input signal is on, the control section 30 can momentarily display "On" on the 7-segment LED display 230, and in the case where the input signal is off, the control section 30 can momentarily display "Off" on the 7-segment LED display 230. That is, the control section 30 can display the content of pressing the multifunction key 217 for a predetermined time or more on the 7-segment LED display 230. The 7-segment LED display 230 is one example of a display section.

[0087] On the other hand, in a case where the multifunction key 217 is pressed for a time shorter than the predetermined time, for example, in a case where it is not pressed for 1 second or more (not pressed for a long time) (NO in step S20), the control section 30 performs the preset input processing (step S50). Then, the control section 30 performs the processing of step S40.

[0088] In step S40, the control section 30 determines whether or not to continue the processing. In a case where the processing is to be continued (YES in step S40), the processing returns to step S10 and the above-described processing is repeated. In a case where the processing is not to be continued (NO in step S40), the processing is ended.

[0089] Note that the multifunction key 217 is one example of the first operation key. Step S50 is one example of the standard processing. Step S30 is one example of the second processing or the selection processing. In addition, step S20, step S30, and step S50 are one example of a procedure of performing either one of the standard processing or the selection processing according to the state at the time when the first operation key is pressed.

[0090] In the power converter 1 of the present embodiment, although it is determined whether or not the multifunction key 217 is pressed for a certain time, for example, the selection processing can be performed in a case where the multifunction key 217 and another key are pressed at the same time. The key that is pressed at the same time as the multifunction key 217 is one example of the second operation key. In addition, for example, the selection processing can be performed in a case where the multifunction key 217 is pressed a plurality of times (for example, two or more times) within a certain period (for example, 0.5 seconds).

[0091] <Effects>

[0092] The power converter 1 of the present embodiment performs either one of the standard processing or the selection processing that is selected from a plurality of input processing candidates by setting, according to the state at the time when the multifunction key 217 is pressed. Therefore, the multifunction key 217 can be switched and used in a case where the standard processing is performed and in a case where the selection processing is performed.

[0093] By switching and using the multifunction key 217 in a case where the standard processing is performed and in a case where the selection processing is performed, the user can instruct the selection processing to the power converter 1 without adding a new key to the touch panel 21.

[0094] In addition, the power converter 1 of the present embodiment can perform the processing that is selected from a plurality of input processing candidates by setting, without preparing a switch and performing wiring, by using the multifunction key 217.

[0095] Further, the power converter 1 of the present embodiment uses the multifunction key 217 to perform the same processing as the processing selected from among a plurality of input processing candidates assigned to any one of the digital input terminals TX1, TX2, TX3, and TX4 by setting. Since the processing assigned to the digital input terminal is the same as the processing assigned to the multifunction key 217, it is possible to perform the processing in a manner that mimics the digital input terminal.

[0096] Note that the power converter 1 of the present embodiment is provided with a plurality of operation keys. In the power converter 1 of the present embodiment, although the multifunction key is one among the plurality of operation keys, it is also possible to be provided with a plurality of operation keys that operate as multifunction keys. That is, in the power converter 1 of the present embodiment, at least any one of the plurality of operation keys can function as a multifunction key when it is pressed.

[0097] Note that the present embodiment disclosed this time should be considered as illustrative in all points and not restrictive. Various modifications can be suggested with regard to the above-described embodiment without departing from the scope and the spirit of the appended claims.

Claims

1. A power converter comprising: an input terminal for inputting an input signal of any of on or off; an operation section provided with a plurality of operation keys including a first operation key for accepting an operation; and a control section, wherein the control section executes a first process selected from a plurality of input process candidates by setting in accordance with the input signal input to the input terminal, and in pressing the first operation key, the control section performs any one of a standard process set in advance or a second process selected from the plurality of input process candidates by setting in accordance with a pressing state at the time of pressing the first operation key.

2. The power converter according to claim 1, wherein in pressing the first operation key for a time longer than a predetermined time, the control section performs the second process, and in pressing the first operation key for a time shorter than the predetermined time, the control section performs the standard process.

3. The power converter according to claim 2, wherein the power converter further comprises a display section, and in pressing the first operation key for a time longer than the predetermined time, the control section displays on the display section a content of pressing the first operation key for a time longer than the predetermined time.

4. The power converter according to claim 1, wherein the plurality of operation keys further include a second operation key for accepting an operation, and in pressing the first operation key and the second operation key at the same time, the control section performs the second process, and in pressing the first operation key and not pressing the second operation key, the control section performs the standard process.

5. A power converter comprising: an input terminal for inputting an input signal of any of on or off; an operation section provided with a plurality of operation keys for accepting an operation; and a control section, wherein the control section executes a first process selected from a plurality of input process candidates by setting in accordance with the input signal input to the input terminal, and in pressing at least any one of the plurality of operation keys, the control section performs any one of a standard process set in advance or a second process selected from the plurality of input process candidates by setting in accordance with a pressing state at the time of pressing the any one of the operation keys.

6. The power converter according to any one of claims 1 to 5, wherein the second process is the same process as the first process.

7. The power converter according to any one of claims 1 to 5, wherein the power converter further comprises a display element, and the control section performs a display process selected from a plurality of display process candidates by setting.

8. A control method of a power converter according to any one of claims 1 to 7, the control method having the following process: in pressing the first operation key, the control section performs any one of a standard process set in advance or a selection process selected from the plurality of input process candidates by setting in accordance with a pressing state at the time of pressing the first operation key. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

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