Discrete variable resistor
Simscape / Electrical / Specialized Power Systems / Passives
The Variable Resistor block represents a linear time-varying resistor. It implements a discrete variable resistor as a current source. The resistance is specified by the Simulink® input signal. The resistance value can be negative.
The block uses the following equations for the relationship between the voltage, v, across the device and the current through the inductor, i, when the resistance at port R is R:
When you use a Variable Resistor block in your model, set the
powergui block Simulation type to
Discrete and select the Automatically
handle Discrete solver and Advanced tab solver settings of blocks
parameter in the Preferences tab. The robust discrete solver is
used to discretize the electrical model. Simulink signals an error if the robust discrete solver is not used.
Input port associated with the resistor. The resistance can be negative.
+— Positive terminal
Specialized electrical conserving port associated with the resistor positive voltage.
-— Negative terminal
Specialized electrical conserving port associated with the resistor negative voltage.
Minimal resistance absolute value (Ohms)— Minimal resistance
1e-4(default) | nonnegative scalar
Lower limit on the absolute value of the signal at port R. This limit prevents the signal from reaching a value that has no physical meaning. The value of this parameter must be greater than 0.