LTC745A101 | 3BHE039905R0101 ABB Voltage Drive Crowbar Circuit Board

The crowbar circuit is used for overvoltage protection in abnormal grid conditions,e.g. loss of grid voltage or short circuit. The converter is equipped with activecrowbar. The crowbar consists of the crowbar unit and a high power resistor.Active crowbar is needed when the converter must stay connected to the grid duringgrid transients, i.e. the converter supports the grid by producing capacitive reactivepower. The crowbar can be switched ON and OFF based on grid voltage transientinfluences on the rotor-side converter. This allows the converter to be connected tothe grid even during very severe grid transient(s)