220V to 380V Inverter

A single-phase 220V to three-phase 380V frequency inverter — also called a 220V-to-380V VFD or a step-up VFD — is a power conversion device that accepts single-phase 220V AC input and produces three-phase 380V AC output at variable frequency. It combines two functions that would otherwise require separate equipment: a voltage step-up converter (to raise 220V to 380V) and a variable frequency drive (to control motor speed and torque).

The conversion is achieved through a boost rectifier stage, which charges an internal DC bus to a voltage higher than the 220V input, followed by a three-phase IGBT inverter stage that synthesises balanced three-phase 380V AC from the elevated DC bus. The output is genuine 380V line-to-line AC — not a reduced-voltage approximation — allowing motors to run at their nameplate rating with full torque and efficiency.

Standard single-to-three-phase VFDs (without the boost stage) output three-phase voltage at the same level as their input — typically 220V three-phase — which cannot drive motors rated at 380V.

Inverter.com's GK3000-CS series frequency inverters specifically address that limitation, accept single-phase 220V–240V AC input and deliver genuine three-phase 380V output — making standard three-phase induction motors operable wherever only single-phase power is available. All models include V/F and sensorless vector control, built-in PID, RS-485 Modbus-RTU, and IP20 enclosure rating.

Key Features of the Single-Phase 220V to Three-Phase 380V VFD

1. Genuine 380V Three-Phase Output from 220V Single-Phase Input: Boost rectifier architecture raises the internal DC bus above input voltage, enabling the inverter stage to synthesise true 380V line-to-line AC. Motors rated at 380V run at full nameplate power and torque — not at a derated voltage.
2. Output Voltage Selectable at 380V, 400V, or 415V: Covers the three standard industrial motor voltage ratings used globally.
3. Output Frequency 0–1000 Hz: Supports standard 50/60 Hz motor operation and high-speed spindle applications up to tens of thousands of RPM on 2-pole motors.
4. V/F and Sensorless Vector Control: V/F control for general variable-speed applications; sensorless vector control (SVC) for applications requiring stable torque at low speed or precise speed regulation under varying load — without a shaft encoder.
5. Built-In PID Controller: Accepts 0–10V or 4–20mA feedback from a pressure, flow, or level transmitter for closed-loop process control. No external controller required for pump, fan, or temperature regulation applications.
6. RS-485 Modbus-RTU: Standard on all models. Full remote control and status monitoring via Modbus registers, compatible with most PLCs, SCADA systems, and HMI panels.
7. Soft Start and Automatic Current Limiting: Ramps motor current smoothly from zero on start-up, eliminating supply voltage dips and mechanical shock. Automatic current limiting reduces output frequency when load approaches the overload threshold, preventing nuisance trips on cyclic loads.
8. Automatic Voltage Regulation (AVR): Compensates for input supply fluctuations within ±15% of nominal, maintaining constant 380V output. Protects motors from undervoltage heating and overvoltage insulation stress — particularly valuable in rural and agricultural grid conditions.
9. IP20 Enclosure, –10°C to +40°C Operating Range: Suitable for panel-mount installation in industrial and agricultural environments. Derate 5% per °C above 40°C.

Benefits of Running Three-Phase 380V Equipment from a Single-Phase 220V Supply

• No three-phase infrastructure required. The most immediate benefit: three-phase 380V motors, compressors, pumps, and machinery can operate at sites served only by single-phase 220V power — farms, rural workshops, residential premises, rented commercial units, temporary construction sites — without applying for a three-phase service upgrade or installing a diesel generator.
• Energy savings versus fixed-speed operation. For centrifugal pump and fan loads, reducing motor speed by 20% cuts power consumption by close to 50% due to the Affinity Laws. Replacing a fixed-speed direct-on-line starter with this drive on a continuously running pump or fan typically recovers the drive's purchase cost within one to two energy billing cycles.
• Eliminates multiple pieces of control gear. A single drive replaces a soft starter (smooth start), an AC contactor (run/stop switching), and a star-delta starter (reduced-voltage starting) — reducing panel complexity, wiring, and maintenance points.
• Motor protection included. Over-current, over-voltage, under-voltage, overheating, phase-loss, and short-circuit protection are built in. Up to 30 fault codes are logged with operating snapshots for post-trip diagnosis.
• Equipment remains relocatable. A machine driven by this VFD can be moved between sites — single-phase or three-phase — without rewiring. At a site with three-phase supply, the drive can be bypassed or used to add variable-speed control; at a single-phase site, it provides the phase conversion and voltage step-up.