Development of an Analog Electronic Wattmeter

The paper deals with the development of an analog electronic wattmeter which is simple in design and can measure power, from very low values to very high values, with simple modifications, at different frequencies and with good order of accuracy. It can also be used in the measurement of power of distorted signals and can be interfaced with out any loading error. Basically, it measures I cosPhi with good order of accuracy and effect of variation of voltage is taken care off by introducing a voltage sensitive resistance. By introducing electronic circuits at different stages, phase angle errors due to imperfections can be compensated. Output voltage, at the final stage, will be proportional to average power of the system.