ABB UNITROL 1000-PM40 excitation controller modules

The ABB UNITROL® 1000-PM40 is a digital excitation controller module designed for synchronous generators and motors, providing precise voltage and reactive power control in power generation and industrial applications.

Key Features of UNITROL 1000-PM40:

✔ Excitation Control – Regulates generator field current for stable voltage & reactive power.

✔ Modular Design – Part of the UNITROL 1000 series, compatible with other PM modules.

✔ Digital Control (DSP-Based) – Fast, precise regulation with advanced algorithms.

✔ Multiple Control Modes:

Automatic Voltage Regulator (AVR) mode (maintains terminal voltage)

Field Current Control (FCR) mode (manual field adjustment)

Power System Stabilizer (PSS) (damping oscillations)

✔ Protection Functions:

Over-excitation/Under-excitation limiting

Field overcurrent & short-circuit protection

Loss-of-excitation detection

✔ Communication Interfaces:

Modbus RTU/RS485 (for SCADA integration)

Optional Ethernet, Profibus, IEC 61850 (depending on configuration)

✔ Redundancy Support – Can be paired with a backup PM module for fail-safe operation.

Typical Applications:

Hydro & thermal power plants

Industrial synchronous motors (e.g., compressors, mills)

Marine & offshore power systems

Grid stability support (reactive power compensation)

UNITROL 1000 Series Overview:

The PM40 is part of ABB's UNITROL 1000 family, which includes:

PM40 (basic regulator module)

PM41 (enhanced with PSS & advanced diagnostics)

PM42 (dual-channel redundant version)

PM boards (for thyristor/IGBT power sections)

Wiring & Connections:

Inputs: Generator terminal voltage (VT), current (CT), field voltage/current feedback.

Outputs: Firing pulses to thyristor bridge (for field excitation).

Auxiliary I/O: Binary inputs/outputs for protection & control.

Why Choose UNITROL 1000-PM40?

✅ Precise voltage regulation for grid compliance.

✅ Robust protection against field faults.

✅ Flexible integration with power plant control systems.