Auto-Measuring system for Track to Earth transition resistance in Subway;

Analysis and research on the ability of distance protection element standing the influence of transition resistance;

The phase selector has overcome the disadvantage of previous phase selectors influenced by the transition resistance,and the principle of the fault selector is simple.

Research on the ability of ultra-high voltage transmission line distance protection standing fault resistance influence;

Ground distance relay based on fault resistance calculation;

The existence of fault resistance may add an additional reactive or capacitive component to the impedance seen by the protection.

Analysis of neutral grounded via a transition resistor;

A novel arcless on-load tap-changing model is proposed,which adopts inverse parallel high-power thyristor as a control switch and regulates the output voltage by switching corresponding tap-changing windings,and uses thyristor s null-current cut-off characteristic to cancel transition resistor input process to simplify the regulation process and accelerate the regulation speed effectively.

It is found out that the two algorithms can both eliminate the influence of transition resistor on the accuracy of fault location,and both have advantages and disadvantages.

To improve reaction sensitivity of ground distance relay to high voltage high resistance ground fault, a new type of action criterion of highly adaptive protection boundary for transient resistances is put forward.

The method is not influenced by the operating mode of the system and transient resistance.

The ability of zero sequence relay against transient resistance under different running conditions is analyzed in detail.

Compensation algorithm of grounding distance protection considering FCL and fault resistance