The closed-loop control system of the all-electric vertical injection molding machine achieves high-precision control of actions such as injection and mold locking through real-time feedback from sensors and dynamic adjustment by the controller. Its debugging process needs to follow the systematic steps of "parameter calibration - interlocking test - accuracy verification". The following is a detailed analysis.

　　I. Basic Inspection and Preparation before Debugging

　　Hardware confirmation: Check whether the wiring of feedback components such as the servo motor, encoder, and grating ruler is firm, and ensure that the grounding resistance of the shielding layer is less than 1Ω to avoid electromagnetic interference. Use a multimeter to measure the power supply voltage of the driver (AC 220V±10%) and the insulation resistance of the motor (≥50MΩ).

　　Software configuration: Import the factory parameter file of the device and verify whether the version of the control program matches. Confirm whether the default values of the PID (proportional-Integral-Derivative) control parameters, such as the position loop gain (Kp) and the velocity loop integral time (Ti), meet the design requirements of the equipment.

　　Mechanical calibration: Measure the parallelism of the template with a dial indicator (error ≤0.03mm/m), manually rotate the ball screw to check the smoothness of transmission, and eliminate the influence of mechanical jamming on closed-loop control.

　　Ii. Step-by-step Calibration of Core parameters

　　Calibration of the position feedback system

　　Encoder zero alignment: Manually retract the screw to the origin position, and set the Z signal of the encoder to zero through the driver operation panel. Repeat this process three times and take the average to ensure positioning accuracy.

　　Grating ruler compensation: Select 5 test points on the moving path of the clamping mechanism. Use a laser interferometer to measure the deviation between the actual displacement and the feedback value. Correct the pitch error through the controller compensation table (the compensation accuracy should be < ±0.002mm).

　　2. Closed-loop regulation of speed and pressure

　　Speed loop optimization: Set up three test segments of low speed (50mm/s), medium speed (150mm/s), and high speed (300mm/s), observe the overshoot of the motor response curve (less than 5%) and the adjustment time (less than 0.3s), and dynamically adjust the proportional parameters (Kv) of the speed loop.

　　Pressure closed-loop verification: Connect the pressure sensor to the injection cylinder, set three levels of pressure tests at 10MPa, 30MPa, and 60MPa, compare the deviation between the controller's command value and the actual pressure (error ≤±1%), and correct the pressure gain coefficient.

　　Iii. Linkage Testing and Dynamic Compensation

　　Empty cycle test: Perform injection - holding pressure - cooling - mold opening cycles at 50% of the rated speed for 10 times to monitor the synchronization of each axis. If there is an abnormal match between the clamping force and the injection speed (such as flash caused by premature mold opening), the action timing parameters need to be adjusted.

　　Load debugging: Conduct mold trials using test raw materials (such as PP) and collect the melt pressure curve. When the pressure fluctuation exceeds ±2MPa during the pressure-holding stage, the adaptive control function is activated to dynamically adjust the PID parameters to stabilize the pressure curve.

　　Iv. Accuracy Verification and Data Recording

　　Repeat positioning accuracy test: Perform 20 injection actions continuously at the midpoint of the screw stroke. Use a dial indicator to measure the deviation of the end position, with the standard deviation required to be less than ±0.01mm.

　　Long-term stability verification: Run continuously for 8 hours, record the motor temperature rise (< 45℃), current fluctuation (< ±5% of the rated value), and product weight deviation (< ±0.3%) every hour, and form a commissioning report.