Voltage Source Converter (VSC)

We implemented VSC as part of the VSC HVDC FACTS device based on the following source:

A. Panosyan, “Modeling of advanced power transmission system controllers”, Ph.D. dissertation, Gottfried Wilhelm Leibniz Universität Hannover, 2010.

The Voltage Source Converter (VSC), is a power electronic device used to convert alternating current (AC) to direct current (DC) and vice versa. It connects an AC system to a DC system. The VSC is connected with a coupling transformer to the ac system. In pandapower the VSC model includes the coupling transformer and considers it via the input parameters r_ohm and x_ohm.

See also

Unit Systems and Conventions

Create Function

pandapower.create.create_vsc(net, bus, bus_dc, r_ohm, x_ohm, r_dc_ohm, pl_dc_mw=0.0, control_mode_ac='vm_pu', control_value_ac=1.0, control_mode_dc='p_mw', control_value_dc=0.0, name=None, controllable=True, in_service=True, index=None, **kwargs)

Creates an VSC converter element - a shunt element with adjustable VSC internal voltage used to connect the AC grid and the DC grid. The element implements several control modes.

Does not work if connected to “PV” bus (gen bus, ext_grid bus)

INPUT:

net (pandapowerNet) - The pandapower network in which the element is created

bus (int) - connection bus of the VSC

bus_dc (int) - connection bus of the VSC

r_ohm (float) - resistance of the coupling transformer component of VSC

x_ohm (float) - reactance of the coupling transformer component of VSC

r_dc_ohm (float) - resistance of the internal dc resistance component of VSC

pl_dc_mw (float) - no-load losses of the VSC on the DC side for the shunt R representing the no load losses

control_mode_ac (string) - the control mode of the ac side of the VSC. it could be “vm_pu” or “q_mvar”

control_value_ac (float) - the value of the controlled parameter at the ac bus in “p.u.” or “MVAr”

control_mode_dc (string) - the control mode of the dc side of the VSC. it could be “vm_pu” or “p_mw”

control_value_dc (float) - the value of the controlled parameter at the dc bus in “p.u.” or “MW”

OPTIONAL:

name (list of strs, None) - element name

controllable (bool, True) - whether the element is considered as actively controlling or

as a fixed voltage source connected via shunt impedance

in_service (bool, True) - True for in_service or False for out of service

index (int, None) - Force a specified ID if it is available. If None, the

index one higher than the highest already existing index is selected.

OUTPUT:

index (int) - The unique ID of the created ssc

Input Parameters

net.vsc

Parameter	Datatype	Value Range	Explanation
name	string		name of the VSC
bus*	integer		index of ac bus of the ac side of the VSC
bus_dc*	integer		index of dc bus of the dc side of the VSC
r_ohm*	float	\(\geq\) 0	resistance of the coupling transformer
x_ohm*	float	\(\leq\) 0	reactance of the coupling transformer
control_mode_ac*	string		the control mode of the ac side of the VSC
control_value_ac*	float		the value of the controlled parameter at the ac bus
control_mode_dc*	string		the control mode of the dc side of the VSC
control_value_dc*	float		the value of the controlled parameter at the dc bus
controllable*	boolean	True / False	whether the element is considered as actively controlling
in_service*	boolean	True / False	specifies if the VSC is in service.

*necessary for executing a power flow calculation.

Electric Model

Voltage Source Converters VSC are self-commutated converters to connect HVAC and HVDC systems using devices suitable for high power electronic applications, such as IGBTs.

The corresponding terminal-admittance equation is given as:

\begin{align*} \underline{Y}_{T} (\underline{V}_{1} - \underline{V}_{VSC}) = \underline{I}_{1} \end{align*}

Where \(\underline{Y}_{T}\) = 1/\(\underline{Z}_{T}\) is the admittance of the lossless-assumed coupling transformer between the VSC and the ac system. \(\underline{V}_{VSC}\) stands for the VSC output Voltage.

Result Parameters

net.res_vsc

Parameter	Datatype	Explanation
p_mw	float	active power consumption of vsc [MW]
q_mvar	float	reactive power consumption of vsc [MVAr]
vm_internal_pu	float	voltage magnitude at vsc internal bus [pu]
va_internal_degree	float	voltage angle at vsc internal bus [degree]
vm_pu	float	voltage magnitude at vsc ac bus [pu]
va_degree	float	voltage angle at vsc ac bus [degree]