LIBRARY

Analog.Basic.Potentiometer

Adjustable resistor (potentiometer) with three terminals.

The sliding contact is placed between pin_n (r = 0) and pin_p (r = 1), controlled by the input signal r. The total resistance R is split into two sections by the wiper position:

$$R_p=R_{actual}\cdot (1-r^{\prime }),R_n=R_{actual}\cdot r^{\prime }$$

where r' = \min(1, \max(0, r)) is the clamped wiper position and

$$R_{actual}=R\cdot (1+\alpha \cdot (T_{heatPort}-T_{ref}))$$

The voltage drops follow Ohm's law for each section:

$$v_p-v_c=R_p\cdot i_p,v_n-v_c=R_n\cdot i_n$$

Kirchhoff's current law at the potentiometer:

$$i_p+i_n+i_c=0$$

Corresponds to Modelica.Electrical.Analog.Basic.Potentiometer.

Usage

ElectricalComponents.Analog.Basic.Potentiometer(R=1.0, T_ref=293.15, alpha=0.0)

Parameters:

Name	Description	Units	Default value
R	Total resistance at reference temperature	Ω	1
T_ref	Reference temperature	K	293.15
alpha	Linear temperature coefficient of resistance	1/K	0

Connectors

• pin_p - This connector represents an electrical pin with voltage and current as the potential and flow variables, respectively. (Pin)

• pin_n - This connector represents an electrical pin with voltage and current as the potential and flow variables, respectively. (Pin)

• contact - This connector represents an electrical pin with voltage and current as the potential and flow variables, respectively. (Pin)

• r - This connector represents a real signal as an input to a component (RealInput)

• heat_port - This connector represents a thermal port with temperature and heat flow as the potential and flow variables, respectively. (HeatPort)

Variables

Name	Description	Units
Rp	Resistance from pin_p to contact	Ω
Rn	Resistance from contact to pin_n	Ω
LossPower	Power dissipated in the potentiometer	W

Behavior

$$\begin{array}{rl}\mathtt{pin}\mathtt{\_}\mathtt{p}\mathtt{.}\mathtt{i}\left(t\right)+\mathtt{contact}\mathtt{.}\mathtt{i}\left(t\right)+\mathtt{pin}\mathtt{\_}\mathtt{n}\mathtt{.}\mathtt{i}\left(t\right)& =0\\ \mathtt{Rp}\left(t\right)& =R(1+(-\mathtt{T}\mathtt{\_}\mathtt{ref}+\mathtt{heat}\mathtt{\_}\mathtt{port}\mathtt{.}\mathtt{T}\left(t\right))\mathtt{alpha})(1-min(1,max(0,r\left(t\right))))\\ \mathtt{Rn}\left(t\right)& =R(1+(-\mathtt{T}\mathtt{\_}\mathtt{ref}+\mathtt{heat}\mathtt{\_}\mathtt{port}\mathtt{.}\mathtt{T}\left(t\right))\mathtt{alpha})min(1,max(0,r\left(t\right)))\\ \mathtt{pin}\mathtt{\_}\mathtt{p}\mathtt{.}\mathtt{v}\left(t\right)-\mathtt{contact}\mathtt{.}\mathtt{v}\left(t\right)& =\mathtt{Rp}\left(t\right)\mathtt{pin}\mathtt{\_}\mathtt{p}\mathtt{.}\mathtt{i}\left(t\right)\\ \mathtt{pin}\mathtt{\_}\mathtt{n}\mathtt{.}\mathtt{v}\left(t\right)-\mathtt{contact}\mathtt{.}\mathtt{v}\left(t\right)& =\mathtt{pin}\mathtt{\_}\mathtt{n}\mathtt{.}\mathtt{i}\left(t\right)\mathtt{Rn}\left(t\right)\\ \mathtt{LossPower}\left(t\right)& =(\mathtt{pin}\mathtt{\_}\mathtt{n}\mathtt{.}\mathtt{v}\left(t\right)-\mathtt{contact}\mathtt{.}\mathtt{v}\left(t\right))\mathtt{pin}\mathtt{\_}\mathtt{n}\mathtt{.}\mathtt{i}\left(t\right)+\mathtt{pin}\mathtt{\_}\mathtt{p}\mathtt{.}\mathtt{i}\left(t\right)(\mathtt{pin}\mathtt{\_}\mathtt{p}\mathtt{.}\mathtt{v}\left(t\right)-\mathtt{contact}\mathtt{.}\mathtt{v}\left(t\right))\\ \mathtt{heat}\mathtt{\_}\mathtt{port}\mathtt{.}\mathtt{Q}\mathtt{\_}\mathtt{flow}\left(t\right)& =-\mathtt{LossPower}\left(t\right)\end{array}$$

Source

"""
Adjustable resistor (potentiometer) with three terminals.

The sliding contact is placed between `pin_n` (r = 0) and `pin_p`
(r = 1), controlled by the input signal `r`. The total resistance
`R` is split into two sections by the wiper position:

math R_p = R_{actual} \cdot (1 - r'), \quad R_n = R_{actual} \cdot r'

where `r' = \min(1, \max(0, r))` is the clamped wiper position and

math R_{actual} = R \cdot (1 + \alpha \cdot (T_{heatPort} - T_{ref}))

The voltage drops follow Ohm's law for each section:

math v_p - v_c = R_p \cdot i_p, \quad v_n - v_c = R_n \cdot i_n

Kirchhoff's current law at the potentiometer:

math i_p + i_n + i_c = 0

Corresponds to `Modelica.Electrical.Analog.Basic.Potentiometer`.
"""
component Potentiometer
  "Positive pin"
  pin_p = Pin() {
    "Dyad": {
      "placement": {
        "diagram": {"iconName": "default", "x1": -50, "y1": 450, "x2": 50, "y2": 550, "rot": 0}
      },
      "tags": []
    }
  }
  "Negative pin"
  pin_n = Pin() {
    "Dyad": {
      "placement": {
        "diagram": {"iconName": "default", "x1": 950, "y1": 450, "x2": 1050, "y2": 550, "rot": 0}
      },
      "tags": []
    }
  }
  "Wiper (sliding contact)"
  contact = Pin() {
    "Dyad": {
      "placement": {
        "diagram": {"iconName": "default", "x1": 950, "y1": 950, "x2": 1050, "y2": 1050, "rot": 0}
      },
      "tags": []
    }
  }
  "Wiper position input: 0 = at pin_n, 1 = at pin_p"
  r = RealInput() {
    "Dyad": {
      "placement": {
        "diagram": {"iconName": "default", "x1": 50, "y1": 1000, "x2": -50, "y2": 1100, "rot": 90}
      },
      "tags": []
    }
  }
  "Thermal port for heat exchange"
  heat_port = HeatPort() {
    "Dyad": {
      "placement": {
        "diagram": {"iconName": "node_a", "x1": 460, "y1": 960, "x2": 560, "y2": 1060, "rot": 0}
      },
      "tags": []
    }
  }
  "Total resistance at reference temperature"
  parameter R::Resistance = 1.0
  "Reference temperature"
  parameter T_ref::Temperature = 293.15
  "Linear temperature coefficient of resistance"
  parameter alpha::LinearTemperatureCoefficient = 0.0
  "Resistance from pin_p to contact"
  variable Rp::Resistance
  "Resistance from contact to pin_n"
  variable Rn::Resistance
  "Power dissipated in the potentiometer"
  variable LossPower::Power
relations
  pin_p.i + pin_n.i + contact.i = 0
  Rp = R * (1 + alpha * (heat_port.T - T_ref)) * (1 - min(1, max(0, r)))
  Rn = R * (1 + alpha * (heat_port.T - T_ref)) * min(1, max(0, r))
  pin_p.v - contact.v = Rp * pin_p.i
  pin_n.v - contact.v = Rn * pin_n.i
  LossPower = (pin_p.v - contact.v) * pin_p.i + (pin_n.v - contact.v) * pin_n.i
  heat_port.Q_flow = -LossPower
metadata {
  "Dyad": {
    "labels": [{"label": "$(instance)", "x": 500, "y": 1100, "rot": 0}],
    "icons": {"default": "dyad://ElectricalComponents/Potentiometer.svg"}
  }
}
end

Flattened Source

"""
Adjustable resistor (potentiometer) with three terminals.

The sliding contact is placed between `pin_n` (r = 0) and `pin_p`
(r = 1), controlled by the input signal `r`. The total resistance
`R` is split into two sections by the wiper position:

math R_p = R_{actual} \cdot (1 - r'), \quad R_n = R_{actual} \cdot r'

where `r' = \min(1, \max(0, r))` is the clamped wiper position and

math R_{actual} = R \cdot (1 + \alpha \cdot (T_{heatPort} - T_{ref}))

The voltage drops follow Ohm's law for each section:

math v_p - v_c = R_p \cdot i_p, \quad v_n - v_c = R_n \cdot i_n

Kirchhoff's current law at the potentiometer:

math i_p + i_n + i_c = 0

Corresponds to `Modelica.Electrical.Analog.Basic.Potentiometer`.
"""
component Potentiometer
  "Positive pin"
  pin_p = Pin() {
    "Dyad": {
      "placement": {
        "diagram": {"iconName": "default", "x1": -50, "y1": 450, "x2": 50, "y2": 550, "rot": 0}
      },
      "tags": []
    }
  }
  "Negative pin"
  pin_n = Pin() {
    "Dyad": {
      "placement": {
        "diagram": {"iconName": "default", "x1": 950, "y1": 450, "x2": 1050, "y2": 550, "rot": 0}
      },
      "tags": []
    }
  }
  "Wiper (sliding contact)"
  contact = Pin() {
    "Dyad": {
      "placement": {
        "diagram": {"iconName": "default", "x1": 950, "y1": 950, "x2": 1050, "y2": 1050, "rot": 0}
      },
      "tags": []
    }
  }
  "Wiper position input: 0 = at pin_n, 1 = at pin_p"
  r = RealInput() {
    "Dyad": {
      "placement": {
        "diagram": {"iconName": "default", "x1": 50, "y1": 1000, "x2": -50, "y2": 1100, "rot": 90}
      },
      "tags": []
    }
  }
  "Thermal port for heat exchange"
  heat_port = HeatPort() {
    "Dyad": {
      "placement": {
        "diagram": {"iconName": "node_a", "x1": 460, "y1": 960, "x2": 560, "y2": 1060, "rot": 0}
      },
      "tags": []
    }
  }
  "Total resistance at reference temperature"
  parameter R::Resistance = 1.0
  "Reference temperature"
  parameter T_ref::Temperature = 293.15
  "Linear temperature coefficient of resistance"
  parameter alpha::LinearTemperatureCoefficient = 0.0
  "Resistance from pin_p to contact"
  variable Rp::Resistance
  "Resistance from contact to pin_n"
  variable Rn::Resistance
  "Power dissipated in the potentiometer"
  variable LossPower::Power
relations
  pin_p.i + pin_n.i + contact.i = 0
  Rp = R * (1 + alpha * (heat_port.T - T_ref)) * (1 - min(1, max(0, r)))
  Rn = R * (1 + alpha * (heat_port.T - T_ref)) * min(1, max(0, r))
  pin_p.v - contact.v = Rp * pin_p.i
  pin_n.v - contact.v = Rn * pin_n.i
  LossPower = (pin_p.v - contact.v) * pin_p.i + (pin_n.v - contact.v) * pin_n.i
  heat_port.Q_flow = -LossPower
metadata {
  "Dyad": {
    "labels": [{"label": "$(instance)", "x": 500, "y": 1100, "rot": 0}],
    "icons": {"default": "dyad://ElectricalComponents/Potentiometer.svg"}
  }
}
end

Test Cases

No test cases defined.

Related

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  • Constant

  • FixedTemperature

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  • VoltageSource