[ERROR] Genrou: pmech signal attached with no linked governor

[pelesh]

Example GenrouTest1_Ieeet1_Json_no_arg fails with following error:

26: Test timeout computed to be: 1500
26: Example: TwoBusIeeet1Json
26: Input file: "/Users/src/gridkit/build-gcc/examples/PhasorDynamics/Tiny/TwoBus/Ieeet1/TwoBusIeeet1.json"
26: [ERROR] Genrou: pmech signal attached with no linked governor
26: [ERROR] Component errors: 1
26: terminate called after throwing an instance of 'std::runtime_error'
26:   what():  SystemModel allocation failed
2/2 Test #26: GenrouTest1_Ieeet1_Json_no_arg ...Subprocess aborted***Exception:   0.03 sec

I believe the check at the line below may be overzealous and is causing this failure:

GridKit/GridKit/Model/PhasorDynamics/SystemModel.hpp

Line 332 in 8c92cc2

if (errorCount > 0)

If I comment out the exception, everything works correctly.

I don't think that at this point we can check if a governor is connected to the generator because governor may have not been allocated/connected at this point.

CC @nkoukpaizan

Originally posted by @pelesh in #313 (comment)

[pelesh]

It may also be that we need to reconsider the system assembly rules at this point. As far as I remember, we originally implemented signal nodes so that signal outputs are set at allocate stage and signal inputs at initialize stage. The generator in this case should not be setting its input signals.

[nkoukpaizan]

This is very surprising. The problem should be well posed in this case, with a generator, an exciter and a governor, so the test should pass (errorCount should be 0).
I get (after adding some debug statements where the check is done for signals):

test 26
    Start 26: GenrouTest1_Ieeet1_Json_no_arg

26: Test command: /Users/97k/Documents/My-Documents/Codes/GridKit/build_gcc/examples/PhasorDynamics/Tiny/TwoBus/Ieeet1/TwoBusIeeet1Json
26: Working Directory: /Users/97k/Documents/My-Documents/Codes/GridKit/build_gcc/examples/PhasorDynamics/Tiny/TwoBus/Ieeet1
26: Test timeout computed to be: 1500
26: Example: TwoBusIeeet1Json
26: Input file: "/Users/97k/Documents/My-Documents/Codes/GridKit/build_gcc/examples/PhasorDynamics/Tiny/TwoBus/Ieeet1/TwoBusIeeet1.json"
26: PM signal attached.
26: PM signal linked.
26: Max error in |V| = 0.000125153
26: Max error in  w  = 2.12733e-05
26: Max error in  Efd  = 0.00797708
26:
26:
26: Complete in 0.517053 seconds
2/2 Test #26: GenrouTest1_Ieeet1_Json_no_arg ...   Passed    0.56 sec

[PhilipFackler]

The check causing the error is here:

GridKit/GridKit/Model/PhasorDynamics/SynchronousMachine/GENROUwS/GenrouImpl.hpp

Line 324 in 8be144a

Log::error() << "Genrou: pmech signal attached with no linked governor\n";

My understanding is that the governor would be linked here:

GridKit/GridKit/Model/PhasorDynamics/Governor/Tgov1/Tgov1Impl.hpp

Line 159 in 8be144a

signals_.template getSignalNode<Tgov1InternalVariables::PM>()->set(&y_[2], &(this->getVariableIndex(2)));

And this happens before verify() is called.

[pelesh]

The check causing the error is here:

GridKit/GridKit/Model/PhasorDynamics/SynchronousMachine/GENROUwS/GenrouImpl.hpp

Line 324 in 8be144a

Log::error() << "Genrou: pmech signal attached with no linked governor\n";
My understanding is that the governor would be linked here:

GridKit/GridKit/Model/PhasorDynamics/Governor/Tgov1/Tgov1Impl.hpp

Line 159 in 8be144a

signals_.template getSignalNodeTgov1InternalVariables::PM()->set(&y_[2], &(this->getVariableIndex(2)));
And this happens before verify() is called.

Please read my earlier comment. I don't think input signals should be verified at the allocate stage because there is no guarantee that all outputs are allocated and set at that time. At least that was the case in the original implementation of signal nodes.

[PhilipFackler]

I an unable to reproduce this bug. And I have verified the following sequence:

1. PM signal is "attached" to Genrou device during SystemModel constructor
   

   GridKit/GridKit/Model/PhasorDynamics/SystemModel.hpp

   Line 159 in 8be144a

   gen->getSignals().template attachSignalNode<GenrouExternalVariables::PM>(getSignal(pmech));

2. PM signal is "assigned" to Tgov1 device during SystemModel constructor
   

   GridKit/GridKit/Model/PhasorDynamics/SystemModel.hpp

   Line 197 in 8be144a

   gov->getSignals().template assignSignalNode<Tgov1InternalVariables::PM>(getSignal(pmech));

3. PM signal is "set" (i.e., linked) by Tgov1 device during allocate() step
   

   GridKit/GridKit/Model/PhasorDynamics/Governor/Tgov1/Tgov1Impl.hpp

   Line 159 in 8be144a

   signals_.template getSignalNode<Tgov1InternalVariables::PM>()->set(&y_[2], &(this->getVariableIndex(2)));

   
   called from
   

   GridKit/GridKit/Model/PhasorDynamics/SystemModel.hpp

   Line 309 in 8be144a

   component->allocate();

4. PM signal is verified by Genrou device during verify() (this check succeeds for me)
   

   GridKit/GridKit/Model/PhasorDynamics/SynchronousMachine/GENROUwS/GenrouImpl.hpp

   Lines 320 to 327 in 8be144a

   	if (signals_.template isAttached<PM>())
   	{
   	if (!signals_.template isLinked<PM>())
   	{
   	Log::error() << "Genrou: pmech signal attached with no linked governor\n";
   	ret += 1;
   	}
   	}

   
   which is done at the end of SystemModel::allocate()
   

   GridKit/GridKit/Model/PhasorDynamics/SystemModel.hpp

   Line 331 in 8be144a

   int errorCount = this->verify();

[pelesh]

Thank you @PhilipFackler and @nkoukpaizan for the clarifications. I cannot reproduce this behavior anymore, so I am going to close this issue.