Comparison calibration is of great significance for the maintenance and improvement of sensor measurement accuracy， but it is easy to be limited by the field environment， and the cost is expensive. The accuracy of electric grid is constantly updated， and it is increasingly difficult to find an external reference. In order to solve this problem， a self-calibration method of sensor error function was proposed based on the principle of circular closure and the translation law of Fourier series. The error sequence values of electric field time-grating were shifted by 2π/n angular displacement， error sequence values with different phase shift times were used for spectrum analysis to compensate each other for missing harmonic components， finally， the sensor error function was reconstructed using each harmonic component. Accordingly， a self-calibration application platform was designed and built. The experimental results show that the self-calibration method is effective in compensating the periodic errors contained in the electric field time-grating angular displacement sensor. measurement period， the calibration accuracy obtained by using the self-calibration method is similar to that obtained by using the grating as the reference， the measurement error of two different self-calibration methods is 0.05"， and the measurement period error is reduced by 67%. Over the full measurement range， the measurement error of two different self-calibration methods is 0.15"， and the full measurement error dropped by 80%. Compared with the conventional comparison and self-calibration method， the self-calibration method has significant advantages in efficiency， application range and calibration cost.