6-Pulse Bridge (2019)

 Name for Identification

Text

Optional text parameter for identification of the component.

 Thyristor Direction

Choice

Select Up or Down. Up signifies rectifier operation, whereas Down signifies inverter operation

Firing Order Input

Choice

Select Angle in Radians, Array of 6 Pulses, 6 Pulses + 6 Interp. times or Angle in Degrees. This input configures the external alpha order input (AO) depending on how the bridge is to be controlled. See Firing and Blocking Control and Setting Up Firing Control for more details

Use Snubber Circuit

Choice

Select Yes or No. See Snubber Circuit for more details

Transformer Phase Shift

REAL

Constant

Enter a transformer phase shift between -180° and 180° degrees [deg].

If the transformer valve side is lagging, then the phase shift should be entered as a negative value. For example, a Yd1 transformer configuration corresponds to -30°.

Unblock Time

REAL

Constant

The valve group will be locked until this time

has passed.

Graphics Display

Choice

Select 3 phase view, or Single line view

 Rated Frequency

REAL

Constant

The system rated frequency [Hz]

PLO Proportional Gain

REAL

Constant

The proportional gain constant GP for the Internal Phase Locked Oscillator (PLO)

PLO Integral Gain

REAL

Constant

The integral gain constant GI for the Internal Phase Locked Oscillator (PLO)

PLO Reference Voltage

Choice

Select Bus Voltage, Bus Voltage, Zero Sequence Removed, Star Source Voltage or Delta Source Voltage. This input adds a phase shift directly to the PLO output in order to account for the converter transformer configuration. The phase shift angles are summarized as follows:

• Bus Voltage: 30° lead (not used in HVDC)

• Bus Voltage, Zero Sequence Removed: No Phase Shift

• Star Source Voltage: 30° lag

• Delta Source Voltage: 60° lag

See Choosing a Converter Transformer for more details

 Thyristor ON  Resistance

REAL

Constant

Resistance of all thyristors when in the ON state (conducting) [W]

Thyristor OFF Resistance

REAL

Constant

Resistance of all thyristors when in the OFF state [W]

Forward Voltage Drop

REAL

Constant

Forward voltage drop for all thyristors. This input may be 0 [kV]

Forward Breakover Voltage

REAL

Constant

Forward break-over voltage for all thyristors. Thyristors will be forced into conduction if this voltage is exceeded (with or without a gate pulse)  [kV]

Protected Against Forward Breakover

Choice

Select Yes or No.  

If Yes is selected, the valve group will send a firing pulse just before the Forward Breakover Voltage is exceeded, avoiding permanent failure to the thyristor.

Reverse Withstand Voltage

Choice

Select Same As Forward Breakover Voltage or Specify.

Reverse Withstand Voltage

REAL

Constant

Enter the reverse withstand voltage [kV].  This input is enabled only if Reverse Withstand Voltage | Specify is selected.

Minimum Extinction Time

REAL

Constant

Minimum extinction time for all thyristors. Thyristors will re-fire if the voltage exceeds Forward Voltage Drop within the this time since last turn off [ms]

Snubber Capacitance

REAL

Constant

Enter a value for snubber capacitance.  See Snubber Circuit for more details [mF]

Snubber Resistance

REAL

Constant

Enter a value for snubber resistance. See Snubber Circuit for more details [W]

 Firing Pulse Array(6) Name

REAL

Output

Name for the 6-element array of firing pulses. Array number corresponds with valve number

Snubber Circuit Current Array(6) Name

REAL

Output

Name for the 6-element array of snubber circuit currents.  Array number corresponds

with valve number [kA]

Valve Voltages Array(6) Name

REAL

Output

Name for the 6-element array of valve voltages. Array number corresponds with valve number [kV]

Valve Current Array(6) Name

REAL

Output

Name for the 6-element array of valve currents. Array number corresponds with valve number [kA]