PSI - Issue 33

Nassima Naboulsi et al. / Procedia Structural Integrity 33 (2021) 989–995 Nassima Naboulsi et al. / Structural Integrity Procedia 00 (2019) 000–000

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Fig. 1. Filament extruder.

Fig. 2. Heating system control block diagram.

2.1. PID corrector The PID corrector controls the power supply and regulates the power delivered to the heating collars by comparing the setpoint with the values measured by the sensor in order to maintain that the setpoint value is always reached. The objective is to develop an optimal control and to determine the best control structure for the heating process by improving performance in terms of stability, precision and speed. 1 ( ) p I D K K C p K p p    (1) 1 ( 1 ) p d I C p K T p T p          (2) where K p is the proportional gain, K I the integral gain, K D the derivative gain, T I the integral time constant and, T D the derivative time constant. The three terms have respectively the following roles on the system performance: The first one ' The proportional term ' acts on the response time, the second one ' The integral term ' affects the static error and the third one ' The derivative term ' ensures the speed of the system.