AN ELECTRIC CHARGING SYSTEM, A POWER MEASURING INSTRUMENT AND A MOBILE TERMINAL FOR AN ELECTRIC CHARGING SYSTEM AND A CONTROL METHOD THEREOF

PURPOSE: An electric fee payment system, an electric measuring device therefor, a portable terminal, and a control method thereof are provided to impose differentiated payments by calculating electric fees according to time. CONSTITUTION: An electric amount measuring device (201) measures electric usage rates in the time of a consumer (210) and stores information for the electric usage rates by encrypting the information with encryption codes (215). Applications and the encryption key of a calculation device are installed in a portable terminal by enabling the portable terminal to download the applications and the encryption key from a service provider of an electric fee payment system (220). The electric rate measuring device recognizes the portable terminal and connects the portable terminal to the electric rate measuring device (230) when the portable terminal is approached to the electric rate measuring device. The electric rate measuring device transmits information for electric usage rates and an encryption code to the portable terminal (240) after the electric rate measuring device and the portable terminal are authenticated from each other. The portable terminal transmits the information and the encryption code to a calculation device (205) (245). The calculation device verifies the justification of the information received from the portable terminal by using the encryption code (250) and transmits the information to the portable terminal (255). The calculation device uses fee information in each time and the information, generates charging information (260), and calculates the fees (265). The calculation device notifies the calculated fees to the portable terminal (270). [Reference numerals] (201) Electric amount measuring device; (203) Mobile communication terminal; (205) Calculation device; (210) Measure electric usage rates in the time of a consumer; (215) Store information for the electric usage rates by encrypting the information; (220) Download the applications; (225) Near to the mobile communication terminal; (230) Mutual recognition and connection setting (Association); (235) Mutual authentication; (240,245) Transmit information about the amount of consumed electricity and an encoding code; (250) Verify the correctness of the information about the amount of consumed electricity; (255) Transmit the verification result; (260) Generate fee information; (265) Calculate the fees; (270) Notify the calculated fees