Method for detecting anomalies of active filter current sensor and active filter

The invention provides a detection method which is used for detecting whether a current sensor of an active filter is abnormal or not. The current sensor is configured to detect and acquire a load current on a load. The detection method comprises the steps of obtaining the angle and direction of load fundamental wave current based on load current, obtaining the angle and direction of voltage of a power supply, and comparing the obtained angle and direction of the load fundamental wave current with the obtained angle and direction of the voltage of the power supply to judge whether the current sensor is abnormal or not. The power supply is configured to provide power to a load. Under the condition that no extra hardware circuit is added, the detection method is implemented by improving the controller of the active filter, so that the cost is saved. Moreover, whether the current sensor is abnormal or not is judged from the angle and direction of the fundamental current, and the types of the abnormal conditions