This paper presents the improvement of an ultrasonic pulse generator for a pipeline inspection gauge (PIG), which uses 64 transducers for inspecting distances up to 100 km with an axial resolution fixed at 3 mm and variable speeds between 0 and 2 m/s. An ultrasonic pulse generator is composed of a high-voltage (HV) MOSFETs, driver logic and an HV power supply. We used a DC-HV DC converter device as the HV power supply because it reduces the size of the ultrasound system considerably. However, pipeline geometry and inspection effects such as hammer and shock cause a variable pulse repetition frequency (PRF), producing voltage drops, poor quality of the HV pulse generated, failures in the dimensioning of defects and damage to devices by over-voltage. Our improvement is to implement a control scheme to maintain the high quality of the HV regardless of the variable PRF. To achieve this, we characterized three transfer functions of the DC-HV DC converter, varying the connected load to 10%, 45% and 80%. For the characterization, we used the least squares technique, considering an autoregressive exogenous (ARX) model. Later, we compared three control schemes: (1) proportional-integral-derivative (PID) tuned by simultaneous optimization of several responses (SOSR), (2) PID tuned by a neural network (NN) and (3) PI tuned by the analytical design method (ADM). The metrics used to compare the control schemes were the recovery time, the maximum over-voltage and the excess energy when the shock and hammer effects happen to occur. Finally, to verify the improvement of the HV pulser, we compared the ultrasonic pulses generated for various frequencies and amplitudes using the pulse generator with and without the control scheme.

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This paper presents the development of the digital twin of an electro-pneumatic station composed with 3 pistons, to implement this station in virtual laboratories. The objective of this station is to have an economical alternative for the accomplishment of practices of automation that counts on the capacity to connect through Ethernet with PLCs of the mark of Allen Bradley and with all the PLCs that communicate under the protocol Modbus TCP. Later, in order to develop the digital twin presented in this paper, an electro-pneumatic physical station was taken from the Mechatronics laboratory at the Universidad Tecnológica de Queretaro, the development of this digital twin was done through the free software Blender, complementing it with programming in Python for the Ethernet TCP communication with the different programmable logic controllers. Finally, we carried out the validation of this project through the connection of both the digital twin and the physical station taken as a model, with a ControlLogix PLC. This work will allow the future to implement low-cost virtual laboratories in universities, training centers and interested institutions. The laboratories will have multiple practice scenarios that result in students better prepared in the programming of automated systems in the industry.