Top drive system dynamics health check tool

A processing system comprising:

• a processor comprising a local memory;
• a main memory in communication with the processor;
• an input device in communication with the processor via an interface circuit;
• and
• an output device in communication with the processor via the interface circuit;
• wherein the processor is operable to execute coded instructions stored in the memory device and/or the local memory to:
• communicate with a variable-frequency drive (VFD) via the interface circuit, wherein the VFD is operable to drive a top drive (TD), and wherein the VFD and the TD are part of a VFD-TD system of a well drilling system;
• and
• in response to human-initiation via the input device, automatically:
• determine expected magnitude and phase frequency responses utilizing a model of a control loop for the VFD and the TD;
• generate test data by injecting a sequence of sine wave signals with different, predetermined frequencies to the VFD as TD speed setpoint inputs on top of a constant base speed;
• determine magnitude and phase delay for the different frequency sine inputs to the VFD-TD control loop based on the test data;
• and
• output to the output device an indication of health of the VFD-TD system, wherein the health indication is based on a comparison of the determined magnitude and phase responses with the expected magnitude and phase responses.

A method comprising:

• entering a single input to an input device of a processing system, thereby commencing operation of a processor of the processing system to execute coded instructions stored in memory of the processing system to:
• determine expected magnitude and phase frequency responses of a top drive (TD) driven by a variable-frequency drive (VFD), wherein the VFD and the TD are part of a VFD-TD system of a well drilling system, and wherein determining the expected magnitude and phase frequency responses utilizes a model of a control loop for the VFD and the TD;
• generate test data by injecting a sequence of sine wave signals with different, predetermined frequencies to the VFD as TD speed setpoint inputs on top of a constant base speed;
• determine magnitude and phase delay for the different frequency sine inputs to the VFD-TD control loop based on the test data;
• determine an indication of health of the VFD-TD system by comparing the determined and expected magnitude and phase responses;
• and
• output the health indication via an output device of the processing system.