KR0157649B1 - Watt hour meter - Google Patents

Abstract

The present invention relates to a power supply complex meter, and converts the current value measured in the current transformer and measures the effective pulse using the voltage value and the voltage value modulated by the pulse width measured by the voltage transformer and instrument,

In the instrument transformer outputs a phase value at a voltage value via an abnormal circuit and a pulse width modulation circuit,

By outputting an invalid pulse at a voltage value converted from the current value and a voltage value via the pulse width modulation circuit,

Regarding the effective pulse, the phase value and the invalid pulse, the user can easily and simply check the operating status, total power, power for power factor measurement, reactive power for power factor measurement, maximum demand power, current demand power, and current time. It is designed to be compatible with other devices around you.

Description

Power supply complex instrument

1 is a block diagram showing a schematic configuration of the present invention,

(a) shows the configuration of analog circuits for power measurement,

(b) shows the configuration of digital circuits for analysis and display of power,

2 is an external front view of the present invention showing the display portions,

(a) shows the current display state,

(b) shows the display state of the meter reading date.

* Explanation of symbols for main parts of the drawings

2a-2c: current-voltage converter 4a-4c, 9a-9c: pulse width modulator

5a-5c, 11a-11c: Multiplier 6,12: Integrator

7,14: voltage-frequency converter 8a-8c: fault

10: imaging detection unit 15: input compensation unit

16: central control processing unit 20: hardware control processing unit

The present invention relates to a precision multi-function meter for power supply, in particular, installed in a commercial or industrial consumer to measure the precision power, the total power for power factor measurement, the reactive power for power factor measurement, and the maximum demand power to provide details to the user The present invention relates to a precision multi-function meter for power supply.

In general, it is well known that an integrated electric power meter reads an effective amount of power for use in setting a charge while accumulating and displaying the sum of power consumed within a certain time.

In addition, a normal power meter is used to measure the effective power amount, a precision power meter is used to measure the daily power and the maximum demand power, and a time switch and a reactive power meter are additionally installed to measure the reactive power amount by the power factor measurement. It was.

In addition, it is necessary to replace the installed electricity meter when the billing system or the method of power supply is changed while using power in business or industrial customers. It is difficult to measure the electrical characteristics in various ways for the efficiency of power supply by itself. Inconvenient and there was a problem that a separate facility must be added.

Accordingly, an object of the present invention is to provide a power supply complex meter combined with a transformer transformer for the instrument to have the functions of a precision power meter, a reverse side precision power meter, a reverse side reactive power meter and a time switch at the same time.

To this end, the present invention outputs an effective pulse by using a voltage value obtained by converting a current value measured by a current transformer and a voltage value measured by an instrument transformer and modulating a pulse width, and converting the abnormal circuit and the pulse width modulation circuit from the instrument transformer. A phase value is output from the voltage value passed through, and an invalid pulse is output from the voltage value changed from the current value and the voltage value passed through the pulse width modulation circuit, thereby operating state with respect to the valid pulse, phase value, and invalid pulse. Power consumption, power for power factor measurement, reactive power for power factor measurement, maximum demand power, current demand power, and current time are displayed so that users can easily and simply check the power supply status and compatibility with other devices around them. will be.

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

The first detecting the value of the current consumption through each of the four wires according to the power of the three-phase supplied through the three wires not shown in the figure as the current value of the proper magnification by the inverse of the internal winding ratio Current transformer (la), second current transformer (1b) and third current transformer (lc), and the current value detected in the first to third current transformers (la) to (lc) by outputting the voltage value, respectively A first current-voltage converter 2a, a second current-voltage converter 2b, and a third current-voltage converter 2c,

A first instrument transformer (PT) that detects the value of the voltage applied through the wire at an appropriate magnification, that is, a voltage value proportional to the voltage, depending on the turns ratio.

3a, the second instrument transformer 3b, and the third instrument transformer 3c,

A first pulse width modulator for modulating each pulse width according to a modulation signal with respect to the voltage values from the first to third instrument transformers 3a to 3c and outputting the duty cycle in a duty cycle ( A first multiplier 5a, a second multiplier 5b, and a third multiplier 5c each performing time division multiplication according to the on / off state by the pulse width duty cycles from 4a) to 4c;

A first integrator 6 in which the voltage values from the first to third multipliers 5a to 5c are sequentially input through an analog switch not shown in the figure and output at a voltage proportional to the instantaneous power;

A first voltage-frequency converter configured to receive a voltage proportional to the instantaneous power output from the first integrator 6 and output a frequency proportional to the voltage, that is, a frequency proportional to the instantaneous power, as an effective pulse WP; 7) with,

A first abnormal part for inputting a voltage value proportional to the load power from the first to third instrument transformers 3a to 3c and outputting a phase-shifted reactive voltage value shifted by? Phase Shifter) 8a, the second abnormal part 8b and the third abnormal part 8c,

A fourth pulse width modulator 9a which receives the reactive voltage value which is phase-converted from the first to second abnormalities 8a to 8c, modulates each pulse width according to a modulation signal, and outputs the pulse width duty cycle; ), The fifth pulse width modulator 9b and the sixth pulse width modulator 9c,

An imaging detector 10 for outputting a phase value PE according to a ground fault or a short circuit of an input wire from the phases of pulse width duty cycles input from the fourth to sixth pulse width modulators 9a to 9c; ,

Pulse widths are received from the fourth to sixth pulse width modulators 9a to 9c while receiving voltage values proportional to power consumption from the first to third current-voltage converters 2a to 2c. A fourth multiplier 11a, a fifth multiplier 11b, and a sixth multiplier 11c each performing time division multiplication according to a state turned on / off by the duty cycle;

A second integrator 12 which sequentially inputs the voltage values from the fourth to the multipliers 11a to 11c through an analog switch not shown in the figure, and converts and outputs the voltage in proportion to the instantaneous reactive power;

The voltage-frequency converter 14 receives a voltage proportional to the instantaneous reactive power from the second integrator 12 so that the instantaneous reactive power is not affected by the frequency;

An input compensator 15 that receives the effective pulse WP, the phase value PE, and the invalid pulse QP, and compensates for the weakening or the conversion by noise during signal transmission;

While receiving the normal effective pulse WP, the phase value PE, and the invalid pulse QP via the input compensator 15, the clock generator 17 receives the time setting clock and receives the power amount pulse signal, which is effective. A central control processor 16 for outputting a pulse compensation signal and an invalid pulse compensation signal;

A time invalid pulse compensation unit 18 for receiving an invalid pulse compensation signal from the central control unit 16 and outputting a modulated signal to the fourth to sixth pulse width modulators 9a to 9c;

A time-effective pulse compensation unit 19 for receiving an effective pulse compensation signal from the central control unit 16 and outputting a modulated signal to the first to third pulse width modulators 4a to 4c;

While receiving the power pulse signal from the central control unit 16, the clock generator 21 receives the clock for setting the time and the control signal according to the user's processing operation from the switch operation unit 22 to receive various display signals. A hardware control processor 20 for outputting,

The corresponding LEDs 24a, 24b, and 24c of the first display unit 24 are inputted from the hardware control processing unit 20, respectively, while receiving a power meter operation display signal, a reactive power meter operation display signal, a no-measurement display signal, and a power failure display signal. A first display driver 23 for selectively blinking 24d to indicate that the power meter is in operation state (Kwh), the reactive power meter operation state (Kvarh), no metering (or counter current flow) or power failure;

The display signal for the accumulated power amount from the hardware control processing unit 20 to the present from the hardware control processing unit 20 is received from the hardware control processing unit 20 and the six digits (for example, 7027.31 and the second display unit 26). The second display driver 25 for notifying the cumulative total daily power amount up to the present by a number of six digits including two decimal places;

A third display driver which receives the power factor measurement signal for power factor measurement from the hardware control processor 20 and informs the cumulative amount of power in the power factor measurement time period to the present by 6 digits (for example, 0255.81) through the third display unit 28; With 27,

A fourth display driver for receiving the reactive power amount display signal for power factor measurement from the hardware control processor 20 and notifying the cumulative reactive power amount of the power factor measurement time period by a number of six digits (for example, 0028.14) through the fourth display unit 30 ( 29) and,

A fifth display driver 31 which receives the screen display signal from the hardware control processor 20 and indicates whether or not to read the meter while expressing no display or meter reading through the fifth display unit 32;

A sixth display driver 33 which receives the maximum demand power display signal from the hardware control processor 20 and informs the maximum demand power up to the present after the last reading through the sixth display unit 34 by four digits;

The seventh display driver 35 which receives the cumulative maximum demand power signal from the hardware control processor 20 and informs the cumulative maximum demand power of the demand power or the meter reading date in four digits through the seventh display unit 36. )Wow,

An eighth display driver 37 which receives a time display signal or a power factor display signal from the hardware control processor 20 and informs the eighth display unit 38 of two-digit power factor of the current demand time or power factor of 100 percent; ,

The ninth display unit receives the time display signal from the hardware control processing unit 20 and informs the ninth display unit 40 of the current hour / minute (12:13) or the month / day (10.24) to be read. The display driving units 39 are configured.

The power supply and demand composite instrument of the present invention configured as described above allows the power charged in the battery to be used in case of power failure while supplying all the internal parts with the driving power of DC which is full-wave rectified AC power dropped through a transformer (Pwer Trans former). The current of each phase flowing through the wire through the first to third current transformers 1a to 1c is detected at a predetermined ratio and converted by the first to third current-voltage converters 2a to 2c. The width of the pulse through the first to third pulse width modulators 4a to 4c with respect to the set voltage value and the voltage value of each phase detected by the first to third instrument transformers 3a to 3c. The necessary values are obtained on the basis of the pulse width modulation duty cycle modulated by the phase shift and the phase shifted reactive voltage value phase shifted by [pi] / 2 via the first to third or more portions 8a to 8c.

The above voltage value is subjected to time division multiplication in the first to third multipliers 5a to 5c in accordance with the on / off state by the pulse width duty cycle, and then again proportional to the instantaneous power by the first integrator 6. The voltage is obtained to output the effective pulse WP from the first voltage-frequency converter 7.

The phase-change reactive voltage values are modulated by the fourth to sixth pulse width converting units 9a to 9c and outputted as pulse width duty cycles, and then the phase detection unit 10 detects the phases of the wires. While outputting the phase value PE according to the ground or short circuit,

In the fourth to sixth multipliers 11a to 11b according to the state where the above voltage values are turned on / off by the pulse width modulation duty cycles from the fourth to sixth pulse width modulations 9a to 9c. Performing a time division multiplication and converting and outputting a voltage proportional to the instantaneous reactive power by the second integrator 12 and receiving a frequency correction signal from the frequency correction unit 13 so that the instantaneous reactive power is not affected by the frequency; The voltage-frequency converter 14 outputs an invalid pulse QP.

Therefore, the input compensator 15 compensates the values due to loss or noise with respect to the effective pulse WP, the phase value PE, and the invalid pulse QP, and then inputs them to the central control processor 16. It outputs the effective pulse compensation signal and the reactive pulse compensation signal as well as the strategic amount pulse signal of the reactive power amount.

The invalid pulse compensation signal and the effective pulse compensation signal are respectively passed through the fourth to sixth pulse width modulators 9a to 9c via the timed invalid pulse compensator 18 and the timed valid pulse compensator 19, respectively. The modulated signals are output to the first to third pulse width modulators 4a to 4c.

The hardware control processing unit 20 receiving the above-mentioned power amount pulse signal divides the clock from the clock generator 21 and calculates the time, and sets the meter reading month set using a switch (not shown) of the switch operation unit 22. When the date is reached, the cumulative amount from the previous meter reading date until now is stored in the internal memory (not shown), and the maximum demand power and current demand power are reset to zero.

While performing the metering operation, the electricity meter of the first display unit 24 through the first display driver 23 to the ninth display driver 39 flashes the operation state display LED 24a, and the operation of the electricity meter is performed. Whether or not the reactive power meter is operating while flashing the status indicator LED 24b, whether there is no metering or reverse current flow while flashing the non-metered status indicator LED 24c, and whether the power failure is indicated by flashing the power failure status indicator LED 24d Let me know

The second display unit 26 informs the cumulative power and the amount of power up to the present by six digits, and the third display unit 28 informs the cumulative reactive power amount of the power factor measurement time to the present by six digits, and the fifth display. (32) displays no display, the sixth display section (34) displays the maximum demand power up to the present after the last meter reading in four digits, and the seventh display section (36) shows the demand power for the hanging demand time by four. The number of digits is displayed, the elapsed time of the hanging time set in the eighth display section at 15 minute intervals is displayed as two digits from 00 to 14, and the current hour and minute is displayed on the ninth display section 40. Flashes the clones once per second, displaying as a four-digit number.

On the other hand, the meter reading date is displayed alternately with the above-described current screen at a predetermined time period, and the cumulative previous power amount of the meter reading date is displayed in six digits on the second display unit 26, and the power factor of the meter reading date is displayed on the third display unit 28. The cumulative reactive power amount of the measurement time period is displayed by 6 digits, the cumulative reactive power amount of the heat rate measurement time period of the meter reading date is displayed by 6 digits on the fourth display part 30, and the meter reading is displayed on the fifth display part 32. On the sixth display unit 34, the maximum demand power of the meter reading day is displayed in four digits, and the power factor of the meter reading day is displayed on the eighth display unit 38 as a percentage value of two digits, and the ninth display unit 40 is displayed. The period between the month and day will blink, indicating the month and day of the meter as a four-digit number.

Therefore, according to the power supply and demand multi-function meter of the present invention, the precise power amount, the reactive power amount for power factor measurement, and the maximum demand power are displayed by dividing them into detailed items as well as the current display and meter reading date are different from each other. It can be seen that it is precisely understood.

Claims (3)

A first voltage-frequency converting section 7 for outputting an effective pulse with respect to a voltage value proportional to the instantaneous power from the first integrator 6, and the first to third abnormalities 8a to 8c. The phase detection unit 10 detects the phase by receiving the reactive voltage value from and outputs the phase value according to a short circuit or ground fault, and outputs an invalid pulse with respect to a voltage proportional to the instantaneous reactive power from the second integrator 12. In the power supply / complex instrument comprising the second voltage-frequency converters 14, the power pulse signal and the effective pulse compensation are received while the effective pulse, the phase value and the invalid pulse are input through the input compensator 15. For setting the time from the clock generator 21 while receiving a pulse signal of the amount of active power and the amount of reactive power from the central control processor 16 for outputting a signal and an invalid pulse compensation signal, Pulse and switch control panel 22 The first to ninth display drivers 23 are input to the first to ninth display parts 24, 26, 28, 30, 32, 34, 36, 38, and 40 by receiving a switch operation signal. (25) (27) (29) (31) (33) (35) (37) (39) through operation and status, total power, reactive power for power factor measurement, no display / reading, maximum demand power, cumulative maximum A power supply and demand multi-function instrument comprising a hardware control processing device (20) for displaying the power demand, the power factor of the meter reading and the meter reading days. 2. The hardware control processing unit 20 according to claim 1, wherein the elapsed time of the current demand time is two digits (00 to 100) while the current state is displayed on the eighth display unit 38 through the eighth display driver 37. A power supply and demand multi-function meter that displays power factor in two digits while the status of meter reading is indicated. The method of claim 1, wherein the hardware control processing unit (20) displays the current time (00: XX) while displaying the current state on the ninth display unit (40) through the ninth display driver (39). Meter reading during status display. Multi-function multi-function instrument for displaying days (00: XX).