I3PM – Identification of a three parameter model

Block SymbolLicensing group: ADVANCED

Function Description
The I3PM block identifies a three-parameter system model using the method of generalized moments. Unlike the PIDMA block, it is necessary to independently control the identification experiment. The block provides estimated parameters on the outputs p1-6 in one of the following forms, depending on the value of the ips input:

0: First-order model with transport delay given as $F_{F O P D T} (s) = \frac{K}{τ s + 1} \cdot e^{- D s}$ , where p1 = $K$ , p2 = $D$ , p3 = $τ$ ,
1: Input and output moments, where p1 = $m u_{0}$ , p2 = $m u_{1}$ , p3 = $m u_{2}$ , p4 = $m y_{0}$ , p5 = $m y_{1}$ , p6 = $m y_{2}$ ,
2: Process moments, where p1 = $m p_{0}$ , p2 = $m p_{1}$ , p3 = $m p_{2}$ ,
3: Process characteristic numbers, where p1 = $κ$ , p2 = $μ$ , p3 = $σ^{2}$ , p4 = $σ$ . For more information on characteristic numbers, see the documentation of the PSMPC block.

Outputs p7 and p8 are reserved for later use.

This block does not propagate the signal quality. More information can be found in the 1.4 section.

Input

u	Input of the identified system	Double (F64)
y	Output of the identified system	Double (F64)
u0	Input steady state	Double (F64)
y0	Output steady state	Double (F64)
RUN	Execute identification	Bool
CLR	Block reset	Bool
ips	Meaning of the output signals	Long (I32)
	0 .... FOPDT model 1 .... moments of input and output 2 .... process moments 3 .... characteristic numbers

Parameter

tident	Duration of identification [s] $⊙$ 100.0	Double (F64)
irtype	Controller type (control law) $⊙$ 6	Long (I32)
	1 .... D 2 .... I 3 .... ID 4 .... P 5 .... PD 6 .... PI 7 .... PID
ispeed	Desired closed loop speed $⊙$ 2	Long (I32)
	1 .... Slow closed loop 2 .... Normal (middle fast) CL 3 .... Fast closed loop

Output

p1..p8	Identified parameter	Double (F64)
BSY	Busy flag	Bool
RDY	Outputs valid (ready flag)	Bool
E	Error indicator	Bool
	off .. No error on ... An error occurred
iE	Error code	Long (I32)
	1 .... Premature termination 2 .... mu0=0 3 .... mp=0 4 .... sigma^2<0

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