JPS61281973A - Data collector - Google Patents

Abstract

PURPOSE:To reduce the time required for measurement by handling the instantaneous values of AC current and voltage as a digital value by using a microcomputer. CONSTITUTION:A CPU 309 reads the instantaneous values detected by a current transformer 302 and a voltage transformer 304 and calculates the square values of instantaneous electric power and instantaneous current and the square value of instantaneous voltage. The CPU reads in these values by as much as a specified number of times and transfers the data via a shift register 315 to a CPU 314. The CPU 314 integrates the data into a RAM 317 at every time when the data is transferred therein. The CPU 314 calculates the electric energy, the average effective values of the current and voltage, average apparent power, average power factor, average reactive power, etc. within the time limit when a timer 318 detects that the predetermined time limit for measurement is attained. These values are stored together with the data and time into the RAM 317. The CPU 314 transmits the data stored in the RAM 317 through a telephone circuit to the outside if there is a call from the outside.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a function for efficiently collecting data to grasp the power demand situation through a communication line.

(b) Description of the Prior Art FIG. 2 shows an example of a method conventionally used to collect data to examine the temporal distribution of electric power in order to understand the electric power demand situation. The operation will be explained with reference to FIG.

The current flowing through the power line 201 is detected by the current transformer 202, and the voltage applied thereto is detected by the voltage transformer 203. When this signal is input to the power pulse generator 204, the power amount becomes a constant value. Each time a signal is reached, a signal is obtained in the form of an electrical pulse. This pulse and pulses generated at constant time intervals from the timer 205 are recorded on a two-channel analog recording magnetic cassette tape device 206.

To collect data, the magnetic cassette tapes 207 contained in the magnetic cassette tape device are collected, and the recorded time pulses and power pulses are read by a reading device to create temporal distribution data.

+i Problems to be Solved by the Invention In the method shown in FIG. 2, it takes time to read data from a magnetic cassette tape and process the data, and there is a risk that the data may be changed by reproduction noise from recording. Furthermore, it is time consuming to collect the magnetic cassette tape every time data is collected.

The present invention solves these problems and improves voltage, current, and power factor other than electric energy.

This allows data such as reactive power to be collected simultaneously and clarifies the correlation between each data.

B) Means for Solving the Problems FIG. 1 is a functional block diagram showing the overall configuration of the present invention.

In this figure, 101 is a power line to be measured, and a current transformer 102 is used to detect the current flowing through this power line. A voltage transformer 103 that detects the voltage applied between the power lines
．． A sample-and-hold amplifier 104 that simultaneously and independently samples instantaneous values of voltage and current and holds the values.
．． A multiplexer 105 that switches input of current values and voltage values to the A/D converter, an A/D converter that converts analog signals such as current and voltage into digital values, 106. Calculation,
Data processing unit 10 consisting of a microprocessor, program memory, and data memory for performing data processing
7. A timer 108r that supplies a timing signal A transmitting/receiving unit 109 that transmits collected data in response to an external request A communication line 1 connected to the transmitting/receiving unit
It consists of 10.

(E) The instantaneous value inputs of the operating current and voltage are selected by the multiplexer 105 from the sample-and-hold amplifiers 104-1 and 104-2, respectively, by the microprocessor of the processing unit 107 in FIG. It is converted into a digital value at 106. The processing unit 107 reads the digital input, multiplies the instantaneous values of current and voltage, calculates the instantaneous power for this sample value, calculates the square of the instantaneous value of current, and squares the instantaneous value of voltage. It performs calculations to calculate values and temporarily stores these data in an internal storage device. By repeating these predetermined series of operations, collecting instantaneous data, and performing arithmetic operations on this data, data for the required amount can be obtained.

The amount of power is calculated by accumulating the instantaneous power and multiplying it by the sample interval.The effective values of current and voltage are obtained by taking the average value over a certain period of the square value of the instantaneous value and square rooting it. .

Each piece of data obtained in this way is stored in the processing device 107, and when a call signal for data collection is received from the outside, it is retrieved from the data processing device 107 via the transmitting/receiving unit 1o9.

(f) Example FIG. 3 is a configuration diagram of a data collection device according to the present invention.

In the figure, a CPU (A1309 is an 8-bit multi-chip type microcomputer) 310 is a read-only memory ROM for storing programs, and 311 is a memory 9RAM for storing and temporarily storing data. (AJ) It also includes a digital input interface 3-13 for connecting the data sample 307 and the CPU.Furthermore, in order to control various operations on the collected data and data transmission to the outside, an 8-bit multichip type Microcomputer CPU
(Equipped with B1314 and accompanying program memory ROM (B+316 data memory RAM (
B+317 and CPU prisoner 309 to CPU (Bi3
There is a shift register 315 for sending data to 14 and a timer fBl 31B for timed transmission of data collection.

For data transmission to the outside, as an example, a configuration is shown in which data is collected using a telephone line. The communication adapter 319 functions to establish a communication line and to match the format of the data to be sent to match the communication method and conditions on the receiving side. The modem 320 functions to convert signals into a form that can be carried on the telephone line, and converts signals on the telephone line into signals in a form that can be handled by the collection device. The N CU 321 detects the arrival of a calling signal. The other components have the same functions as those explained in the section (e) Function.

The operation of the CPU prisoner 309 is performed as shown in the flowchart of FIG. ” ).

Calculate the square value (U2) of the instantaneous voltage. After reading the specified number of times, the CP is transferred via the shift register 315.
U (Pass data to B1314. CPU U (B1
314 operates as shown in the flowchart in FIG. 4-B, and each time data is sent, it is accumulated in the RAM (B1317), and a timer (Bl 318) is used to indicate that the CPU (B1314) has reached a predetermined measurement time limit. When detected, the power amount, average effective value of current/voltage, average apparent power, average power ratio, average reactive power, etc. within this time limit are calculated and stored in RAM (B1317) along with the date and time.

When there is a call from the outside, the CPU (B1314) operates as shown in the flowchart in FIG.
The data stored in 17 is sent out via the telephone line according to a prescribed format.

The above embodiments have been explained for single-phase circuits, but similarly, single-phase 3-wire, 3-phase 3-wire, and 3-phase 4-wire circuits can also be explained.
If the number of current/voltage detection sections is increased according to the number of lines and the number of phases, and the program is made compatible with each method, a data collection device with similar functions can be realized.

(g) Effects As explained above, according to the present invention, by using a microcomputer to treat instantaneous values of alternating current and voltage as digital values, power transmission and distribution such as electric energy, current, voltage, power factor, reactive power, etc. Data to know the situation can be obtained at the same time, the codified data can be read out without going to the measurement point, and the data can be input directly to the host computer, reducing the time required for measurement. I can do it.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing the overall configuration of the present invention, Fig. 2 is a diagram showing a conventional method, Fig. 3 is an embodiment of the present invention, and Figs. 4 and 5 are embodiments. 3 is a flowchart showing the operation of the microcomputer in FIG. Patent applicant: Takemoto Electric Instrument Co., Ltd. 102°Kameryuhen blc! 1 +03: Voltage transformer +04: Supply/pull/hold amplification 106 each + multiplexer +06: A/DI converter body 2W! I
1o7: Data Department 11! Dairy friend b: Timer 206
=Magnetic cassette tape device No. 7: Magnetic cassette tape player σ diagram Gatorpu (Amendment for filing procedure (spontaneous) Patent application 2 filed on June 7, 1985, title of the invention and 6-Doyu 9' data )
3. Relationship with the case of the person making the amendment Patent Applicant's Specification 5, Statement of Contents of Amendment, page 9, line 14, ``Brief Description of Drawings'' is amended to 4, ``Brief Description of Drawings'' .

Claims (1)

[Claims] In devices that collect the amount of electricity supplied or consumed over time, the instantaneous values of current and voltage are measured at a high-speed sampling frequency that is asynchronous to the power supply frequency, and the data is digitized and sent to a microcomputer. Load it into the computer and calculate the amount of electricity, average effective value of current and voltage, average apparent power, average power factor, average reactive power, etc. within a specified time limit.
A data collection device configured to accumulate the results over time and enable data transmission by reading commands from an external communication line.