Measurement circuit and method of alternating current sampling value phase error of intelligent substation

The invention discloses a measurement circuit and method of the alternating current sampling value phase error of an intelligent substation. The circuit mainly comprises a clock analysis module, a frequency multiplication module, a signal conditioning module, an analog-digital conversion module, an Ethernet fiber receiver, an Ethernet MAC, an Ethernet PHY and a CPU processor, wherein the CPU processor obtains the sampling value of a merging unit from the Ethernet MAC, obtains the sampling circuit of the circuit from the analog-digital conversion module, obtains the sending time of sampling value message from effective pulse, and performs phase error computation. The measurement circuit is used for measuring the phase error caused by the accessing of the merging unit, and avoids the direct measurement of a conditioning circuit and rated time delay.