The converters control layer is the layer which controls the
VSC units in VSC-HVDC control system. It receives the
instructions from the pole control layer and feedbacks the
information from the next control layers to the pole control
layer, more than it judges the information whether meet the
requirements, adjust real-time the instruction that convey to the
next layers. According to the instructions such as DC voltage,
DC power, AC voltage or frequency supplied by pole control
layer, it compares the instruction with the measured value to
adjust the PWM pulse various parameters for making the
measured value equal to the instruction. DC voltage maximum
limit control, power rate of variation control, sequence control
about converters units opening and locking, emergency
locking