Electric Machinery’s (EM) brushless excitation system consists of a high frequency AC generator (armature & field) and rotating rectifier bridge.

EM’s brushless excitation system provides high reliability through elimination of brushes, collector rings and carbon dust, which in turn greatly reduces inspection and maintenance costs. Rotating rectifier redundancy with detection of diode failure which in operation allows for more convenient maintenance intervals.

EM is the industry leader in brushless excitation for 2 pole turbine generators with over 500 units installed. EM brushless exciters are used by generator manufacturers worldwide to meet brushless requirements.

EM brushless exciters offer customers many advantages including:

• Series redundant diode designs and parallel fused diode designs are available to ensure continuous service
• Various designs are available to match current voltage and shaft mounting arrangements
• No exciter outboard bearing is required which eliminates alignment problems associated with three bearing arrangements
• The shaft driven permanent magnetic generator pilot exciter provides a reliable source of exciter field power that eliminates bulky power transformers and dependence on station battery for field flashing
• Short circuit sustaining capability provides fault current support
• No heavy bus work or cable connections are required between excitation cubicles and the generator, thus simplifying installations
• Large expensive field field circuit breaker and field discharge resistors are not required
• Compact voltage regulator hardware for installation and control panel or switchgear eliminates large excitation cubicles