Ultra-low-frequency cosine square wave-based parameter acquisition circuit and dielectric loss angle calculation method

The invention discloses an ultra-low-frequency cosine square wave-based parameter acquisition circuit and a dielectric loss angle calculation method. According to the circuit, a cosine square wave control generator is electrically connected with a divider resistor and a current transformer, and the cosine square wave control generator is used for generating ultra-low-frequency cosine square waves and controlling the polarity switching of an ultra-low-frequency cosine square wave power supply; the input end of a signal gain module is electrically connected with the divider resistor and the current transformer, and the output end of the signal gain module is electrically connected with an acquisition card; and the output end of the acquisition card is in communication connection with a processing module, and the acquisition card is in communication connection with the cosine square wave control generator and used for high-frequency acquisition of parameters after receiving a trigger signal. With the ultra-low-f