PID Structure Conversion VI

Owning Palette: PID VIs

Requires: Full Development System

Converts a PID controller or controllers in Academic, Parallel, or Series form into the form (Academic) and PID gains units that the PID VIs expect. Wire data to the proportional, integral, or derivative input to determine the polymorphic instance to use, or manually select the instance.

Details  

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Select an instance PID Structure Conversion (DBL)PID Structure Conversion (DBL Array)

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PID Structure Conversion (DBL)

	proportional unit specifies the units associated with the proportional (P) component of the PID controller to convert. The relationship between the available units is Kc = 100 / PB. 0 Gain (Kc) (default)—Specifies that the proportional component is expressed in terms of proportional gain (Kc). 1 Band (PB)—Specifies that the proportional component is expressed in terms of proportional band (PB).
	PID structure specifies the initial form of the PID controller. Refer to the Details section of this topic for the equations that represent each form. 0 Academic (Standard) (default)—Specifies that the controller is in PID Academic form. 1 Parallel—Specifies that the controller is in PID Parallel form. 2 Series—Specifies that the controller is in PID Series form.
	proportional specifies the value of the proportional (P) component of the PID controller to convert.
	integral specifies the value of the integral (I) component of the PID controller to convert.
	derivative specifies the value of the derivative (D) component of the PID controller to convert.
	integral unit specifies the units associated with the integral (I) component of the PID controller to convert. 0 min (default)—Specifies that the integral component is expressed in minutes. 1 s—Specifies that the integral component is expressed in seconds.
	derivative unit specifies the units associated with the derivative (D) component of the PID controller to convert. 0 min (default)—Specifies that the derivative component is expressed in minutes. 1 s—Specifies that the derivative component is expressed in seconds.
	PID gains returns the updated PID gains parameters, which you can use with other PID VIs. proportional gain (Kc) returns the proportional gain of the controller. integral time (Ti, min) returns the integral time in minutes. derivative time (Td, min) returns the derivative time in minutes.

PID Structure Conversion (DBL Array)

	proportional unit specifies the units associated with the proportional (P) component of the PID controller to convert. The relationship between the available units is Kc = 100 / PB. 0 Gain (Kc) (default)—Specifies that the proportional component is expressed in terms of proportional gain (Kc). 1 Band (PB)—Specifies that the proportional component is expressed in terms of proportional band (PB).
	PID structure specifies the initial form of the PID controller. Refer to the Details section of this topic for the equations that represent each form. 0 Academic (Standard) (default)—Specifies that the controller is in PID Academic form. 1 Parallel—Specifies that the controller is in PID Parallel form. 2 Series—Specifies that the controller is in PID Series form.
	proportional specifies the values of the proportional (P) components of the PID controllers to convert.
	integral specifies the values of the integral (I) components of the PID controllers to convert.
	derivative specifies the values of the derivative (D) components of the PID controllers to convert.
	integral unit specifies the units associated with the integral (I) component of the PID controller to convert. 0 min (default)—Specifies that the integral component is expressed in minutes. 1 s—Specifies that the integral component is expressed in seconds.
	derivative unit specifies the units associated with the derivative (D) component of the PID controller to convert. 0 min (default)—Specifies that the derivative component is expressed in minutes. 1 s—Specifies that the derivative component is expressed in seconds.
	PID parameters returns an array containing the updated PID gains parameters for each controller. You can use the updated values with other PID VIs. proportional gain (Kc) returns the proportional gain of the controller. integral time (Ti, min) returns the integral time in minutes. derivative time (Td, min) returns the derivative time in minutes.

PID Structure Conversion Details

Each PID form produces the same result but incorporates information in a different manner. The following equations describe each form:

PID Academic

PID Parallel

To convert a controller in Parallel form to Academic form, this VI converts the proportional, integral, and derivative values according to their changes in units and applies the following transformations:

K_c = K_p

T_i = K_c / K_i

T_d = K_d / K_p

PID Series

To convert a controller in Series form to Academic form, this VI converts the proportional, integral, and derivative values according to their changes in units and applies the following transformations:

T_i = T'_I + T'_D