N-type Coaxial Power Transfer Standard

High frequency and microwave power are two fundamental parameters of electronic measurement. In order to approach our national electronics measurement to the International System of Units (SI) and ensure the result consistency, establishing the national standards for high-frequency and microwave power measurement is very important. Hence, the study of high frequency and microwave power measurement is of great theoretical and practical value.Since the original power standard in our country is unab le to meet the standard of domestic demand, setting up a new broadband national power standard is critical. The measurement system used in the latest primary power standard was mainly studied in this paper. Ensuring accuracy of measurement and minimizing the system time constant are the key work of the research.The traditional power measurement methods based on the theory of the calorimetric-substitute technique and the principles of control systems were analyzed. The importance of the use of auxiliary control system to shorten the time constant was discussed.The relative measurement and the two steps of mearsurement which were used to improve the veracity had been analyzed.The DC substitute method was been studied and the PID controller was been be modelled in the way of calorifics - electrics conversion.Based on the result,there will be more better if the proportion controller and the integral controller was separated in different situation.