NON-CONTACT POWER SUPPLY SYSTEM, POWER TRANSMITTER, AND FOREIGN MATTER DETECTION METHOD

摘要

PROBLEM TO BE SOLVED: To provide a non-contact power supply system, power transmitter, and foreign matter detection method that are capable of securely detecting a foreign matter between a power transmission coil and power reception coil without being influenced by fluctuations in signal intensity caused by an external factor.SOLUTION: A non-contact power supply system for non-contact supplying power from a power transmission coil 32L of a power transmitter A1 to a power reception coil of a power receiver includes: the power receiver for generating a spread spectrum signal obtained by performing spread spectrum modulation using a reference PN code to transmit the generated signal; the power transmitter A1 comprising a reception antenna 43 for receiving the transmitted spread spectrum signal; a despread demodulation circuit 44 that generates a demodulation PN code whose series is the same as that of the reference PN code, gradually changes the demodulation PN code's phase, and detects a correlation characteristic with a reception PN code included in the spread spectrum signal received by the reception antenna 43; and a communication control unit 45 that detects a foreign matter between the power transmission coil 32L and the power reception coil.SELECTED DRAWING: Figure 5