How to setup the 3 Phase 380VAC output with Shiningintl inverter boards

Shiningintl has launched the single phase 220VAC output inverter board, but inorder to output the 3 phase 380VAC voltage in some application,  it has to create a 3 phase power system,  Shiningintl provides the latest 3 phase 380VAC output solution based on the shiningintl 6KW system

To generate a 3-phase 380V AC output using three 220V single-phase inverters with a 120° phase shift, follow these steps:

Step 1: Hardware Setup

1. Shiningintl 6KW on-grid Inverter board Configuration:
   • Use 3 identical 6KW 220VAC single-phase inverters (ensure they support phase-shifting and synchronization).
   • Label them as Inverter A, B, C.
2. Wiring Connection:
   • Connect the inverters in a star (Y) configuration:
     • Link the neutral terminals (if available) of all inverters to a common neutral point (N).
     • Connect the phase outputs (L1, L2, L3) of each inverter to the three-phase load (U, V, W).

   

Step 2: Phase Shifting

1. Set Phase Angles command:
   • Inverter A: Phase angle = 0° (reference).
   • Inverter B: Phase angle = 120°.
   • Inverter C: Phase angle = 240° (or -120°).
2. Synchronization:
   • set up the 3 inverter boards frequency, and make sure that all inverters share the same frequency (50Hz/60Hz) and phase alignment.
   • the setup method please refer to Shiningintl inverter communication protocols:
     • communication protocols

Step 3: Voltage & Frequency Matching

1. Output Voltage:
   • Set each inverter to output 220V phase voltage.
   • The line-to-line voltage will be:
     Vline=3×220V≈380V (3-phase)Vline​=3​×220V≈380V (3-phase).
2. Frequency Sync:
   • Ensure all inverters operate at the same frequency (e.g., 50Hz ±0.1Hz) to avoid power oscillations.

Step 4: Control & Communication

1. Phase-Locked Loop (PLL):
   • Implement a PLL circuit or software algorithm to lock the phase angles precisely.
   • Tools: MATLAB/Simulink for PLL simulation, or use pre-built inverter firmware.
2. Communication Protocol:
   • Connect inverters via CAN bus, RS485, or Modbus to share phase and frequency data.
   • Example: Use a CANopen protocol for real-time synchronization.

Step 5: Testing & Validation

1. No-Load Test:
   • Measure line-to-line voltages (U-V, V-W, W-U) with a multimeter. They should read ~380V AC.
   • Use an oscilloscope to verify 120° phase differences between waveforms.
2. Load Test:
   • Connect a balanced 3-phase load (e.g., 3-phase motor).
   • Check for voltage stability (±5% tolerance) and neutral current (should be near zero in a balanced system).

Critical Considerations

1. Circulating Currents:
   • Add current-limiting reactors or use droop control to balance currents between inverters.
2. Harmonic Filtering:
   • Install LCL filters at inverter outputs to reduce THD (<5%).
3. Protection:
   • Enable overcurrent/overvoltage protection on all inverters.
4. Shiningintl has fixed all previous problems, and using our 6KW inverter baords to setup this system, it is easy to operation.

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