the electronic apparatus needs to periodically detect its own state, and notify the power supply apparatus of a result of this detection.
However, without supplying power required to detect a state of the electronic apparatus to the electronic apparatus, the electronic apparatus cannot detect its own state, and therefore cannot correctly notify the power supply apparatus of its own state. Therefore, in some cases, the power supply apparatus supplies excessive power to the electronic apparatus even though the power supply apparatus has controlled, with use of the state of the electronic apparatus notified from the electronic apparatus, power to be supplied from the power supply apparatus to the electronic apparatus.London E1 4NS, UK $^{ 14}$Technische Hochschule Aachen, III Physikalisches Institut, Sommerfeldstrasse 26-28, D-52056 Aachen, Germany $^{ 15}$University College London, London WC1E 6BT, UK $^{ 16}$Department of Physics, Schuster Laboratory, The University, Manchester M13 9PL, UK $^{ 17}$Department of Physics, University of Maryland, College Park, MD 20742, USA $^{ 18}$Laboratoire de Physique Nucléaire, Université de Montréal, Montréal, Quebec H3C 3J7, Canada $^{ 19}$University of Oregon, Department of Physics, Eugene OR 97403, USA $^{ 20}$CLRC Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 0QX, UK $^{ 22}$Department of Physics, Technion-Israel Institute of Technology, Haifa 32000, Israel $^{ 23}$Department of Physics and Astronomy, Tel Aviv University, Tel Aviv 69978, Israel $^{ 24}$International Centre for Elementary Particle Physics and Department of Physics, University of Tokyo, Tokyo 113-0033, and Kobe University, Kobe 657-8501,