KR101082424B1 - A multi-function meter with graphic function - Google Patents

Abstract

According to the present invention, the voltage and current output from each electric line are displayed in the form of numerical or waveform signals, and the power, frequency, and power factor are derived using the measured voltage, current, and waveform signals, and then displayed on the display unit. The present invention relates to a composite instrument having a graphic function capable of performing a voltage measurement, comprising: a voltage detecting means for detecting a voltage for each electric line, a current detecting means for detecting a current for each electric line, and an electric line detected from the voltage detecting means and the current detecting means. A control unit for converting a star voltage and a current into a waveform signal form according to a numerical value or a time, and then transmitting it to a display unit, calculating a power factor, power and frequency for each electric line, and transmitting the same to a display unit. The control unit may include a display unit displaying numerical data of voltage and current for each electric line or waveform signal data of voltage and current, power, frequency, and power factor for each electric line converted through the control unit; When a waveform signal having a current or voltage is detected, the waveform signal having a current or voltage above the predetermined level, the current and voltage values detected by the voltage detecting means and the current detecting means, or the waveform signal data, the power and the frequency. A storage unit for storing the power factor; And a control system connected to a management system or controlling the control unit, data stored in the storage unit, numeric data of voltage and current derived through the control unit or waveform signal of voltage and current according to time, and power between voltage and current. It is equipped with a communication unit capable of transmitting overfrequency and power factor to the management system. In addition, the control unit is equipped with an operation unit for converting the information currently displayed on the display unit into another information, or adjusting the PT ratio and CT ratio of the voltage attenuating unit provided in the voltage detecting unit and the current detecting unit and the current transformer. . The composite instrument with the graphic function according to the present invention having such a structure can measure the current and voltage flowing from each electric line, and then express it in the form of a numerical value or a graph. The frequency and power factor can be derived, and then displayed on the display, and the display can show whether the power factor is true or above ground.

Instrument, Instrument, Meter, Voltage, Current, Active Power, Power Factor, Graphic

Description

A MULTI-FUNCTION METER WITH GRAPHIC FUNCTION}

The present invention is a composite instrument having a graphic function that can display the voltage, current, power, frequency and power factor included in each electric line among single-phase or three-phase AC power applied from the outside on one screen. In particular, the present invention relates to a composite instrument having a graphic function for outputting numerical values of the voltage, current, power, frequency, and power factor, and for graphically representing waveform signals of voltage and current.

In general, an integrated power meter that integrates and displays an electric power used so far to check the amount of power used indoors is used on an electric line drawn indoors from the outdoors. The integrated power meter is an electric line drawn from the outside. The amount of power drawn from each load to the load is accumulated, and the accumulated amount of power is displayed on the display unit.

However, since the integrated power meter cannot check an individual voltage or current from an electric line introduced into a home or a factory, a separate multi-point measuring mode may be changed by a manual lever on each electric line. The meters had to be connected in series or in parallel to separately check the current and voltage of each electric line.

In addition, in addition to checking the waveform signal of the current and voltage for each electric line, and to check the power factor between the current and the voltage and whether the current is progressing or the ground, the time on the electric line instead of the multimeter. It was a hassle to connect an oscilloscope that can display changes in current and voltage in the form of waveform signals.

In addition, the multimeter and the oscilloscope as described above had a problem that only the temporary voltage and current change on the electric line had to be checked, and the measurement means and the display means for simultaneously monitoring the change of the voltage and current were not provided. It was not easy to judge the situation of the electric line, and there was no communication means for storing the voltage and current values or waveform signal data measured on each line in the order of time or transmitting to other computing devices. There was a problem that it is too difficult to analyze the cause of the failure of the load connected to the line more closely.

Accordingly, the present invention solves the problems as described above, and detects the voltage and current output from each electric line to display in the form of a numerical or waveform signal, the power factor between the voltage and current and the ground or It is possible to check and display the fact that there is an abnormality, to check the abnormality of the electric line, to check the efficiency of the power output from each electric line, and to determine the cause of the failure of the load equipment branched from the electric line. The goal is to provide a complex instrument with graphical capabilities that can be analyzed closely.

The composite instrument with a graphic function of the present invention for achieving the above object includes a voltage detecting means for detecting a voltage for each electric line, a current detecting means for detecting a current for each electric line, and the voltage detecting means and a current detection. The control unit converts the voltage and current for each electric line detected by the means into a waveform signal form according to the numerical value or time, and then transmits it to the display unit. Equipped.

The control unit may include a display unit displaying numerical data of voltage and current for each electric line or waveform signal data of voltage and current, power, frequency, and power factor for each electric line converted through the control unit, and a predetermined level through the control unit. When a waveform signal having the above current or voltage is detected, the waveform signal having the current or voltage above the predetermined level, the current and voltage values detected by the voltage detecting means and the current detecting means, or the waveform signal data and the electric power. A storage unit for storing a frequency, a power factor, and a power factor; and a control system connected to the control system to control the control unit, or to store data stored in the storage unit, numerical data of voltage and current derived through the control unit, or voltage and current according to time. Waveform signals, and the power factor, frequency and power between voltage and current can be sent to the management system. The communication unit is mounted.

In addition, the control unit is equipped with an operation unit for converting the information currently displayed on the display unit into another information, or adjusting the PT ratio and CT ratio of the voltage attenuating unit provided in the voltage detecting unit and the current detecting unit and the current transformer. .

A complex instrument with a graphic function according to the present invention having such a structure can measure the current and voltage flowing from each electric line using a cheaper low speed microprocessor, and then express it in the form of numerical or signal waveforms. The power, frequency, and power factor may be derived from the measured current and voltage values, and then displayed on the display, and the display may indicate whether the current is advanced or ground.

Therefore, the composite instrument with a graphic function according to the present invention can check the power consumption of the electric line branched to each load, and can check the incorrect wiring of the electric line.

In addition, the power factor between the current and the voltage drawn from each electric line and the fact that the current is advanced or grounded can be grasped in real time to estimate the power efficiency, and the cause of failure of the load equipment branched from the electric line can be estimated. It can work.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

In addition, the terms to be described later are terms defined in consideration of functions in the present invention, which may vary according to intentions or customs of users or operators, and the definition thereof describes a composite instrument having a graphic function according to the present invention. It should be based on the content throughout.

Hereinafter, with reference to the accompanying drawings will be described in detail the present invention.

1 is a control block diagram of a composite instrument with a graphic function according to the present invention, Figure 2 is a detailed block diagram of the voltage detection means and current detection means equipped in the present invention, Figure 3 is a This is a flow chart.

4 is a state diagram in which a plurality of data is displayed on the display unit provided in the present invention.

As shown in these figures, the composite instrument with a graphic function according to the present invention includes a voltage detecting means 3 for detecting a voltage per electric line, a current detecting means 1 for detecting a current per electric line, and the The voltage and current for each electric line detected by the voltage detecting means 3 and the current detecting means 1 are converted into a waveform signal form according to the numerical value or time, and then transmitted to the display unit 5, and at the same time, the power factor for each electric line And a control unit 7 for calculating the over frequency and power, and then transmitting them to the display unit 5.

In addition, the control unit 7 includes a display unit 5 which displays numerical data of voltage and current for each electric line or waveform signal data of voltage and current, and power, frequency, and power factor for each electric line converted through the control unit 7. And, when a waveform signal having a current or voltage of a predetermined level or more is detected through the control unit 7, the waveform signal having a current or voltage of the predetermined level or more, the voltage detecting means 3 and the current detecting means (1). The storage unit 9 for storing current and voltage values or waveform signal data, power, frequency, and power factor detected from the control unit 9 and the management system 11 to control or store the control unit 7. Manage data stored in the unit 9, numerical data of voltage and current derived through the control unit 7 or waveform signals of voltage and current over time, and power, frequency, and power factor between the voltage and current. The communication unit 13 can transmit to the stem 11 is mounted.

In addition, the control unit 7 converts the information currently displayed on the display unit 5 into another information, or the voltage attenuating unit 17 provided in the voltage detecting unit 3 and the current detecting unit 1; An operation unit 15 capable of adjusting a PT (Power Transformer) ratio and a CT (Current Transformer) ratio of the current transformer 23 may be mounted, and the display unit 5 may easily display characters converted into Korean characters. It is preferably made of a graphic LCD.

In addition, the control unit 7 is provided with a microprocessor capable of operation and control to convert the characters to be displayed on the display unit in the form of Hangul.

In addition, as shown in FIG. 2, the voltage detecting means 3 attenuates a high voltage input from each electric line to a predetermined level, and then outputs the attenuated voltage waveform. And an A / D converter 21a that receives an analog voltage of an AC voltage waveform attenuated to a predetermined level via the voltage attenuator 17 and converts the analog voltage into digitized information.

As shown in FIG. 2, the current detecting means 1 drops down to a predetermined level via the current transformer 23 for lowering a high current input from each electric line to a level that can be measured, and the current transformer 23. And a voltage converting section 25 for converting the alternating current into a voltage, and an A / D converting section 21b for receiving an analog voltage of the alternating voltage passed through the voltage converting section 25 and converting it into digitized information. .

In addition, as shown in Figure 1, the communication unit 13 is made of a wired network RS-232 or RS-485 or other network protocols to enable data communication with a separate computing device.

Therefore, the operator receiving data from a remote location through the RS-232 or RS-485 or a network protocol is the numerical data of the voltage and current for each electric line transmitted through the communication unit 13 or the waveform signal data of the voltage and current In addition, the power and frequency and the power factor between the voltage and the current, or whether the current progresses through the waveform signal data or the ground can be checked to improve the efficiency of the effective power or to analyze the cause of the failure of the load connected to the electric line. .

In the composite instrument having a graphic function having such a structure, the control unit 7 describes a process of deriving various data using the voltage detecting unit 3 and the current detecting unit 1 as follows.

First, when each electric line is connected to the composite instrument with the graphic function, the user can use the operation unit 15 and the CT (Current Transformer) ratio and PT (related to the current transformer 23 and the voltage attenuation unit 17). Adjust the power transformer ratio (S1).

Next, the control section 7 is a sampling programmed in the control section 7 to obtain sampling values of 20 voltages and currents per cycle of the waveform signals input from the voltage detecting means 3 and the current detecting means 1. Initialize the variable, ie, the value of 'n' to 1 (S2).

In addition, the controller 7 initializes the value of the timer variable 't' to 0 and operates the timer at the same time to obtain a sampled value at regular time intervals while the waveform signal of voltage and current is in progress for one cycle. (S3)

Next, the control unit 7 uses the A / D converters 21a and 21b provided in the voltage detecting unit 3 and the current detecting unit 1 to input instantaneous voltages v (n Value) and the instantaneous current i (n) value are read (S4), and the read instantaneous voltage v (n) and instantaneous current i (n) values are stored (S5).

Next, the controller 7 calculates various data such as an effective value of a voltage, a current, and power to be displayed on the display unit 5 by using an equation as follows.

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Next, the control unit 7 includes a variable of 't' which is constantly increased by a timer to obtain 20 sampled data values at predetermined time intervals in a waveform signal of voltage and current in one cycle range, and the control unit 7 ) Compare the constant 0.83ms stored in (S7).

In this case, since the repetition time per cycle of voltage and current having a frequency of 60 Hz is 16.6 ms, the 0.83 ms means that the frequency of one cycle can be divided into 20 samples and sampled.

Next, the control unit 7 compares the value of 't' with 0.83 ms (S7), if the value of 't' is less than 0.83 ms, the instantaneous current (i (n)) value and the instantaneous voltage The value of (v (n)) is equal to the previous instantaneous current (i (n)) value and the instantaneous voltage (v (n)) value currently displayed on the display section 5 (S8).

At this time, the instantaneous current i (n) value and the instantaneous voltage v (n) value are displayed on the display unit 5 before the instantaneous current i (n) value and the instantaneous voltage v (n) value. If different from the above, the updated instantaneous current i (n) value and the instantaneous voltage v (n) value are displayed on the display unit 5. (S9)

On the other hand, the updated instantaneous current i (n) and instantaneous voltage v (n) are displayed on the display unit 5, and the instantaneous current i (n) and instantaneous voltage v (n) are displayed. If the value is equal to), go to step (S7) comparing the value of 't' and the constant 0.83ms again and receive the updated data (S8a).

Such a display method is a method suitable for a microprocessor operating at a low speed instead of a microprocessor operating at a high speed, and has an economic advantage in that a manufacturing cost can be reduced in manufacturing a composite instrument.

On the other hand, when the control unit 7 compares the value of 't' with 0.83 ms, if the value of 't' is greater than or equal to 0.83 ms, the control unit 7 performs one cycle of voltage and current. In order to attempt 20 samplings, 1 is added to the value of the sampling variable 'n' (S10), and then it is checked whether the value of 'n' to which the 1 is added is greater than the constant 20 (S11).

In this case, when the value of 'n' is compared with the constant 20, if the value of 'n' is not equal to or greater than 20, the control unit 7 determines the value of 't' to obtain 20 sampling values per cycle. After initializing the value to 0, the process returns to step S11 of operating the timer.

On the other hand, as a result of comparing the value of 'n' with the constant 20, if the value of 'n' is greater than 20, the control unit 7 samples 20 samples sampled while 'n' increases from 1 to 20. Value and the following value derived from the previous step,

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The calculated voltage, current, active power, reactive power, apparent power, frequency, power factor (PF), active power amount, and reactive power amount are calculated using the same, and then the derived result is transmitted to the display unit for display.

Next, the control unit 7 returns to step S2 of initializing the value of 'n' to 1 so that new data can be collected from the current and voltage waveform signals (S13a).

The composite instrument with a graphic function according to the present invention having such a structure can measure the current and voltage flowing from each electric line, and then express it in the form of a numerical or waveform signal, and the power from the measured current and voltage values After deriving the excess frequency and power factor, the display unit 5 can be displayed, and the current can be displayed on the display unit 5 as shown in the display example of FIG.

Therefore, the composite instrument with a graphic function according to the present invention can check the power consumption of the electric line branched to each load, as shown in Figure 4d attached to Figure 4, the electric current is 180 degrees out of phase Incorrect wiring can also be checked.

In addition, as shown in Figures 4e to 4f, it is possible to determine in real time the power factor between the current and the voltage drawn from each electric line and whether or not the progress or ground between the current and the voltage in real time to estimate the efficiency of the power, It is effective to guess the cause of the failure of load equipment branching from the line.

The present invention described above is limited to the above-described embodiments and drawings because various substitutions, modifications and changes are possible to those skilled in the art without departing from the spirit of the present invention. It is not.

1 is a control block diagram of a composite instrument with a graphics function according to the present invention,

2 is a detailed block diagram of a voltage detecting means and a current detecting means according to the present invention;

3 is an operation flowchart of a composite instrument according to the present invention,

4 is a state diagram in which a plurality of pieces of data are displayed on the display unit 5 according to the present invention.

Description of the Related Art [0002]

1. Current detecting means 3. Voltage detecting means

5. Display part 7. Control part

9. Storage 11. Management System

13. Communication unit 15. Control panel

17. Voltage attenuation portion 21a. A / D converter

23. Current transformer 25. Voltage converter

Claims (6)

Voltage detecting means (3) for detecting voltage for each electric line; Current detecting means (1) for detecting electric current for each electric line; The voltage and current for each electric line detected by the voltage detecting means 3 and the current detecting means 1 are converted into a waveform signal form according to a numerical value or time, and then transmitted to the display unit 5, and the power factor for each electric line A control unit 7 which calculates power and frequency and then transmits the power to the display unit 5; A display unit (5) for displaying numerical data of voltage and current for each electric line or waveform signal data of voltage and current, power factor, power, and frequency for each electric line converted through the control unit (7); When a waveform signal having a current or voltage of a predetermined level or more is detected through the control unit 7, the waveform signal having a current or voltage of a predetermined level or more, and the current and voltage values detected by the voltage detecting means and the current detecting means. Or a storage unit 9 for storing waveform signal data, power, frequency, and power factor;  And an operation unit (15) mounted to the control unit (7) for converting the information currently displayed on the display unit (5) to another information. The method of claim 1, The voltage detecting means (3) includes: a voltage attenuator (17) for attenuating a high voltage input from each electric line to a predetermined level and then outputting the attenuated voltage waveform; And an A / D converter (21a) which receives the analog voltage of the voltage attenuator (17) and converts the analog voltage into digitized information. The method of claim 1, The current detecting means (1) includes a current transformer (23) for dropping a high current input from each electric line to a level capable of measuring; A voltage converter 25 for converting an alternating current dropped to a predetermined level via the current transformer 23 into a voltage; And an A / D converter (21b) which receives the analog voltage of the voltage converter (25) and converts the analog voltage into digitized information. delete The method of claim 1, The controller 7 updates the instantaneous voltage and the instantaneous current sampled and updated by the voltage detecting means 3 and the current detecting means 1 when the instantaneous voltage and the instantaneous current value are the same as the previous instantaneous voltage and the instantaneous current value displayed on the display unit. If the updated instantaneous voltage and instantaneous current are not equal to the previous instantaneous voltage and instantaneous current value displayed on the display unit 5 without displaying the voltage and instantaneous current on the display unit 5, the instantaneous voltage and instantaneous current are displayed. (5) A composite instrument with a graphics function, characterized by the display. delete

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