SU534698A1 - Device for measuring active power - Google Patents

Description

(54) DEVICE FOR MEASURING ACTIVE POWER

one

The invention may find a widespread application in case of iamereni51X active powers. circuits with signals of complex shape with established and transient modes of their operation. -5

i Analog-to-digital converters are known: active power transmitters containing quad- °: matching blocks l.

 The lack of analog-digital conversion; Active power transducers with an interval-to-Yu transform into frequency is that their quadrature devices are little accurate and inert.

Closest to the proposed device for measuring active power, containing a resistor, is the same calculator; units, the outputs of which are connected to the adder's codes, and the registering units, 1 which are connected to the outputs of the computing units, 20

The disadvantage of such a device is: low accuracy, due to the fact that the device does not allow receiving output signals proportional to the measured active power, 25

The purpose of the invention, an increase in measurement accuracy, is achieved by the fact that a device for measuring active power, containing a resistor, the same computational blocks, the outputs of which are connected to the inputs of the adder, and the registering blocks that are connected to the outputs of the computational blocks, are entered into two spectrum analyzers, the inputs of which are connected in parallel, one to the resistor, the other to the next section of the circuit, and their single-ended outputs are connected to one from computing blocks.

The drawing shows a block diagram of the device.

The device contains a resistor 1, which is connected in series with the studied one, a part of circuit 2, and two spectrum analyzers. ; 3 and 4, the same computing units 5: including peak detectors 6-3,,:: Adders 9, 10, quadrants 11-13 and; inverters 14 and 15, adder 16 and recording devices 17-20.,

Claims (2)

The device operates as follows C for 1IMOB.in the investigated section of circuit 2 and resistor 1, signals proportional to the voltage and load current, are sent to spectrum analyzers 3 and 4, with single-front harmonic components applied to one of the 5 units, where the active is calculated power of the corresponding harmonic. To this end, constant voltage voltages are removed from peak detectors 6, 7, which are respectively the amplitude values of voltages f and. , and, and to the peak detector 8, the signal is supplied from the adder 9, then the voltages supplied to the quadrants 11-13 are squared, and in the inverters 14, 15 the proportions {Г3) and change the eyyaki. (Here p is the resistance of the resistor 1; E and I. are the amplitude values of the current and voltage of the k-th harmonic} U is the geometric sum of the vectors U and), With the help of a three-input adder 10, the active power of the k-th harmonic is calculated, and the adder 16 outputs A signal proportional to the measured active power that can be fed to a recording device: (oscillograph digital voltmeter, digital printing device) or entered into other computational units. The active powers of the constant component & n and individual harmonics are recorded with recording instruments 17–20. The number of output channels of the spectrum analyzers is chosen based on the required TO measurements. The use of new spectrum analyzers — gains — distinguishes the proposed device from the known analog devices for the intention of active power, since it excludes the component of error caused by the wattmeter voltage winding and extends the frequency range, since the device operates at industrial and high frequencies Each power factor and measures in the selected time interval in the established and transient modes both the total active power and the active power constant component and individual harmonics. A formula for measuring a device for measuring activeness, containing a resistor, the same computational units, whose outputs are connected to the inputs of the adder, and recording units, which are connected to the outputs of the computational units, in order to increase the measurement accuracy , two spectral analyzers were introduced into it, the inputs of which are connected in parallel, one to the resistor, the other to the section of the circuit under study, and their “° No. connected to one,” computing unit. Sources of information taken into account in the examination: 1. USSR author's certificate J9 42O114, cl. G 01 R 21/06, 28.06.72: 2. Electrical measurements. Ed. E. G. Shramkova. Higher School, M., 197, pp. 292-295.