SU1486947A1 - Method and apparatus for determining electric power - Google Patents

Description

The invention relates to measuring equipment. The purpose of the invention is to simplify the measurement of power. The magnitude of the voltage is converted to frequency. The conversion is carried out in positive half-periods. The current is converted into a code in discrete time intervals, inversely proportional to the frequency of the voltage conversion. Power is defined as the sum of the code values of the instantaneous current. The device includes, for the implementation of the method, transducers 1 and 2 of current and voltage, the first and second blocks 3 and 8 of the sign definition, the analog-to-code converter 4, the rectifier 5, the analog-frequency converter 6, and the computing unit 7. 2p.s.f-ly, 1 ill.

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The invention relates to measuring equipment.

The purpose of the invention is to simplify the measurement of power.

The method of measuring Electrical Power is that they measure instantaneous current values, convert them into a code, convert the voltage into positive half-periods to a frequency £ ;, convert the current into a code into discrete time intervals / 5C · = 1 / £; , and. power is determined by the formula

ten

_2

CT

15

^Ν , · '

(one)

where K T

20

25

constant rate; power measurement period; instantaneous code values

The drawing shows a device for implementing the method of determining electrical power.

The device contains measuring transducers 1 and 2 of current and voltage, the first block 3 of the definition of the sign, the Converter 4 analog - code, rectifier 5, the Converter 6 analog-frequency, block 7 calculations and /. 30 second sign determining unit 8, with the output of current measuring converter 1 being connected to the input of the first sign determining unit 3 and converter 4 input analogue — a code whose information output and “Ready” output are connected to information and first inputs of calculation unit 7, the second input of which under the keys to the output of the first block 3 of the sign definition, and the third to the output of the second block 8 of the sign definition, the input of which is connected to the output of the voltage measuring transducer 2 and through the rectifier 5 and the transducer 6 tax-rate - a star- * tovomu input converter 4 analogue code.

The device works as follows. 50

Signal transmitter 2 voltage through the rectifier

5 is fed to the input of the converter

6 analog-frequency. The latter transforms the positive half of the input signal'in a sequence of pulses with a variable repetition rate proportional to the amplitude of the signal.

35

40

55

This sequence of pulses is fed to the starting input of the converter 4 analog-code, thereby allowing the beginning of the conversion of the input signal of the current measuring converter 1. After the conversion from the converter output 4 analog-code to the input of the computing unit 7, the "Ready" signal is received, with which the computing unit 7 reads the digital code from the information outputs of the converter 4 analogue code, as well as information about the sign of the measured current from the output of the first block 3 sign definitions. The obtained values are stored in the random access memory of the computing unit 7.

When the polarity of the input signal of the voltage measuring transducer 2 is changed, which the output signal of the second sign determining unit 8 informs, the calculation unit 7 processes the accumulated information in accordance with expression (1). In this case, the code values of the instantaneous currents are summed up taking into account their signs.

Claims (2)

Formula isob a problem 1. The method of determining electrical power, which consists in measuring instantaneous values of current and converting them into a code that differs from me in that, in order to simplify the measurement of power, the voltage value is converted into positive half periods into the frequency £; , convert current into code into discrete time intervals Λϋ. =! / £ ·, and the power is determined by the formula _2 CT where K T constant rate; power measurement period; Ν. - code value of instantaneous current. 2. A device for determining electrical power, containing a measuring voltage converter, a measuring current converter connected to an analog converter — a code, information outputs and the “Ready” output of which is connected 1486947 6 to the information and the first inputs of the computing unit, characterized in that, in order to simplify the measurement of power, the first and second sign determining blocks, a rectifier and an analog-to-frequency converter are introduced into it, and the output of the current measuring transducer is connected to the input of the first block the definition of the sign, the output of which is connected to the second input of the computing unit, to the third input of which the output of the second. sign definition unit is connected, to the input of which the output of the voltage measuring transducer and the input are connected rectifier, the output of which is connected through the analog-frequency converter to the start input of the analog-code converter.