How to debug the electrical control system of high-speed die-cutting machine?

The electrical control system debugging of high-speed die-cutting machine should follow the principle of "staging, systematization and data quantification", and combine the mechanical motion characteristics and process requirements to ensure the coordinated operation of each subsystem. The following is a debugging guide based on EU standard (EN 60204-1) and industry practice:

First, the system check before debugging

1. Hardware connection verification

Power supply system:

Three-phase five-wire system (380 V 5%, 50Hz), measure the voltage difference of each phase with multimeter ≤ 5 V;

Grounding resistance ≤1Ω (grounding resistance tester), PE line cross-sectional area ≥ 10mm.

Signal line:

The encoder and sensor signal lines are shielded twisted pair, and the single end of the shielding layer is grounded (near the controller end);

The distance between the power line and the signal line is ≥300mm, and the intersection is vertically arranged.

2. Insulation and withstand voltage test

Measure the insulation resistance of the motor winding with a 500V megohmmeter ≥ 10m Ω;

Control circuit withstand voltage test (1500V/1min), leakage current ≤10mA.

Second, the subsystem debugging process

1. Power supply and distribution system

Power-on sequence:

Close the main circuit breaker and observe the power indicator (green);

Start UPS, PLC and HMI in turn, and the self-inspection time of each module is ≤ 30s;

Finally, start the servo driver and IO module.

Voltage monitoring:

Monitor DC24V output ripple ≤ 5% (i.e. ≤ 1.2V) with oscilloscope;

The voltage fluctuation of DC bus of servo driver is ≤ 10% (rated value is 540V).

2. PLC and IO system

Input signal test:

Short-circuit the limit switch, and the LED lamp corresponding to the input point of PLC should be lit;

Using signal generator to simulate sensor signal (such as 4-20mA), the error of PLC analog-to-digital conversion value is ≤ 0.5%.

Output signal test:

Forcibly output relay points, and measure the contact closing resistance ≤ 50mΩ;

Test the response time of solenoid valve ≤20ms (monitor the coil current with oscilloscope).

3. Servo drive system

Parameter initialization:

Set the electronic gear ratio (e.g. motor encoder 20000 pulses/revolution, lead screw 10mm, then numerator = 10000, denominator = 20000);

Speed loop gain ≥1000rad/s, position loop gain ≥3000rad/s (adjusted according to load inertia ratio).

Static debugging:

In manual JOG mode, the motor runs smoothly without vibration (vibration acceleration ≤ 0.5m/s);

Positioning accuracy test: send 10mm instruction, and the actual displacement error is ≤±0.01mm (measured by laser interferometer).

Dynamic performance:

Speed step response time ≤50ms (from 0 to rated speed);

Speed fluctuation caused by sudden load change (20% rated load) is ≤ 2%.

4. Visual registration system

Hardware calibration:

The verticality between the optical axis of industrial camera and the workbench is ≤ 0.1 (measured by goniometer);

Brightness uniformity of light source ≥95% (detected by illuminance meter).

Software calibration:

Using standard calibration plate (accuracy ±0.002mm) for distortion correction, the distortion rate is ≤ 0.1%;

The mapping between visual coordinate system and mechanical coordinate system is established, and the conversion error is ≤ 0.01 mm.

5. Security system

Emergency stop circuit:

Press the emergency stop button, and the system will cut off all power supplies within 0.1s;

After the reset, it is necessary to perform the origin regression again to ensure the position accuracy.

Safety light curtain:

Block any light beam of the light curtain, and the equipment shall be shut down within 0.2s;

Response time test: use a high-speed camera to record the time from light curtain trigger to motor stop ≤ 150 ms.

Third, linkage debugging and performance optimization

1. Synchronous control

Multi-axis synchronization:

The position deviation of the dual drive shaft is ≤±0.005mm (in synchronous operation);

The speed matching error between the pressure shaft and the feeding shaft is ≤ 0.5%.

Flying shear function:

Shear time accuracy ≤ 0.1 (corresponding to mechanical angle);

Shear length error ≤±0.05mm (continuous shearing for 100 times).

2. Dynamic response optimization

Acceleration and deceleration control:

S curve acceleration and deceleration time ≥150ms (to avoid impact);

The jerk limit is ≤ 10000mm/s (adjusted according to the load).

Vibration suppression:

A notch filter (frequency range 50-200 Hz) is added to the speed loop;

When the load inertia ratio is ≥3, the automatic tuning function is enabled.

3. Process parameter test

Die cutting pressure control:

The deviation between the pressure set value and the actual value is ≤ 2% (pressure sensor calibration);

Pressure fluctuation ≤ 1% (at high speed).

Registration accuracy:

Continuous die cutting for 1000 times, the average registration error is ≤±0.02mm and the maximum value is ≤±0.03mm；;

When the temperature changes by 5℃, the registration drift is ≤±0.01mm (temperature compensation algorithm is required).

IV. Compliance Testing and Documentation

1. EMC testing

Radiation interference (RE)≤30dBμV/m(30-1000MHz, distance 10m);

Conducted interference (CE)≤40dBμV(150kHz-30MHz).

2. Energy efficiency assessment

Standby power consumption ≤ 1kW;

Full-load energy efficiency ratio ≥0.85 (conforming to IE3 standard).

3. Acceptance documents

Electrical System Debugging Report: including parameter setting table, test data and waveform diagram;

Safety Function Verification Report: test records of emergency stop response time and light curtain trigger;

CE Certification Document: a test certificate conforming to the standards of EN 60204-1 and EN 55011.

Five, typical troubleshooting

Servo motor overheating:

Check whether the encoder feedback is normal (observe A/B phase waveform with oscilloscope);

Reduce the acceleration and deceleration time constant (for example, from 100ms to 150ms).

Unstable registration:

Clean the camera lens (with clean cloth+IPA solution);

Increase the brightness of the light source (above 1000lux).

PLC communication interruption:

Check whether the baud rate of Modbus RTU matches (9600bps)； by default);

Measure the RS485 differential signal voltage (normal range 2-6V).

Recommended debugging tools:

Laser interferometer (such as Renishaw XL-80) is used for position accuracy measurement;

Power quality analyzer (such as Fluke 435) monitors power harmonics;

Servo debugging software (such as Mitsubishi MR Configurator2) observes the running state of the motor in real time.

Wear an anti-static bracelet (electrostatic voltage ≤100V) when debugging to avoid electrostatic damage to electronic components. For precision die cutting below 0.1mm, it is recommended to verify the final accuracy in a constant temperature and humidity environment (23 0.5℃, 50±5% RH).