This invention relates to a method and circuit arrangement for measuring the in-phase and quadrature components of current in an alternating power supply. Starting from a certain value, the consumer must assume the burden of the electric company for the use of quadrature current in an alternating current power supply. This is because the quadrature currents burden the main line. Consequently, it is necessary to measure the portions of the quadrature current. In many cases, it is just as necessary to measure the portion of in-phase current in order to determine wattage factor cost from both of these current components. From this, the circuit arrangements for the idle wattage compensation must also possess measuring equipment with which the wattage factor over the quadrature current and thereby over the corresponding live voltage and idle wattage can be determined.
Measuring tools for the recording of in-phase current and quadrature current as well as for wattage factors and costs are already established. In the book "Measure Rectifier", published by G. Braun, Karlsurule, West Germany, 1963, pages 90 and 91, such a measuring tool is described. Also, the principal circuit diagram is shown. When measuring the quadrature currents, a potential/voltage meter must be set so that the needle deviation is at a minimum. Only then can the quadrature current component read I.sub.b on the analog indicator.
In the handbook, "Electrical And Heat Technology Measurements", published by Hartman and Braun, 11th Edition, 1963, page 100, it is shown how the quadrature current and in-phase current are measured by means of a multiple instrument. Here too, with a watt voltage meter, the needle deviation must be set at the smallest amount.
In the book "Alternating Current Technology", by F. Koppelmann, 1956, pages 36 through 38, a possibility of measuring the quadrature and in-phase circuit components with a measuring contact is shown. Here, the measuring area is to be adjusted to the neutral passage of the respective component to be measured. The measured value is determined and indicated in a needle type indicator instrument. In order to keep the margin of error at the smallest level, aside from the length of time, the position of the contact phase is also especially important. Lastly, due to the measuring technology used and also because of frequently existing strong overlying components, it is very difficult to determine the in-phase and quadrature current with the necessary exactness. It is not so acceptable to use half conductor diodes in order to determine the contact phase, because the flow voltage from these diodes and the temperature influences on the one-half wave are especially disadvantageous to exact measurement.
USPTO Backgrounds
USPTO Backgrounds