Method for evaluating reliability of electrical power measuring device

A method for evaluating the reliability of an electrical power measuring device that is connected to a connection point between a high-frequency power supply device and a load having a complex impedance, the electrical power measuring device being configured to measure the high-frequency electrical power at the connection point, the method comprising:

• terminating a transmission line of high-frequency electrical power output from the high-frequency power supply device at a reference load having an impedance equal to a characteristic impedance of the transmission line, arranging an electrical power measuring device to be evaluated and a reference electrical power measuring device enabling calculation of the uncertainty of an electrical power measured value in the transmission line, arranging, after the electrical power measuring device to be evaluated and the reference electrical power measuring device, a first impedance conversion device that converts an impedance so that an impedance as viewed towards the reference load side becomes the complex impedance together with arranging a first electrical power measuring device that measures electrical power input to the reference load between the first impedance conversion device and the reference load, and arranging, before the electrical power measuring device to be evaluated and the reference electrical power measuring device, a second impedance conversion device that converts an impedance so that an impedance as viewed towards the reference load side becomes the characteristic impedance together with arranging a second electrical power measuring device that measures electrical power output from the high-frequency power supply device between the second impedance conversion device and the high-frequency power supply device;
• calculating an uncertainty range of the electrical power measured value, according to a prescribed calculation formula, from an electrical power measured value measured by the reference electrical power measuring device and the uncertainty of the reference electrical power measuring device, and calculating a prescribed electrical power measuring range based on an electrical power measured value measured by the first electrical power measuring device and an electrical power measured value measured by the second electrical power measuring device;
• and
• evaluating the reliability of the electrical power measuring device to be evaluated based on the electrical power measured value measured by the electrical power measuring device to be evaluated, the uncertainty range of the electrical power measured value of the reference electrical power measuring device, and the prescribed electrical power measuring range.