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thermistor

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thermistor

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Iconic Diagrams\Thermal\Generators

Use

Domains: Continuous. Size: 1-D. Kind: Iconic Diagrams (Pseudothermal, Electric).

Description

This is a model of a linear thermistor. Thermistors are thermally sensitive resistors and have, according to type, a negative (NTC), or positive (PTC) resistance/temperature coefficient. For linear thermistors the resistance and voltage equation can be written as:

 

R = R_ref*(1 + alpha*(p_th.T - T_ref));

p_el.u = p_el.i * R;

 

where R_ref is the reference resistance at reference temperature T_ref and alpha the temperature coefficient of resistance. The actual temperature of the themistor is given by the pseudothermal port of the model , p_el.T. The heat generated by the thermistor is equal to

 

p_th.dQ = p_el.u * p_el.i;

 

The electrical port p of the thermistor model has separate high and low terminals. The equations are:

 

p_el.i = p_high_el.i = p_low_el.i;

p_el.u = p_el_high.u - p_el_low.u;

 

Interface

Ports

Description

p_el_high

p_el_low

p_th

Both terminals of the Electric port.

 

The pseudothermal port

Causality

 

indifferent p_el

fixed heat flow out p_th

 

Parameters

 

R_ref

T_ref

alpha

Reference resistance [Ohm].

Reference temperature [K].

Temperature coefficient of the resistance []