1. Product Description

3BHE035301R0003 is the base model of ABB UNITROL 1000 series digital Automatic Voltage Regulator (AVR). It is an integrated panel-mounted unit integrating signal acquisition circuit, control logic, IGBT power output module and multi-type communication interfaces. This standard part is designed for excitation control of medium & small synchronous generators, certified with UL and DNV marine certificates. With IP20 protection rating, it is only suitable for installation inside closed indoor control cabinets.

• Power supply range: 110~240VAC, 50/60Hz wide AC input
• Rated DC excitation output: 0~10A
• Operating ambient temperature: -20℃ ~ +60℃
• Communication ports: RJ45 Ethernet, HDLC fieldbus

• Voltage regulation accuracy: ±0.5% of nominal generator terminal voltage

  
  

2. Core Product Functions

1. Closed-loop terminal voltage stabilization: Collect real-time generator voltage signals and dynamically adjust excitation output to stabilize terminal voltage and eliminate voltage deviation caused by load changes.
2. Reactive power sharing for parallel units: Built-in droop control logic to evenly distribute reactive power among multiple parallel generators and avoid circulating current and power imbalance between units.
3. Comprehensive excitation fault protection: Over-excitation, under-excitation and over-current protection functions are integrated, with rotating diode fault monitoring. It will activate limitation or shutdown protection to protect generator rotor windings when faults occur.
4. SOE sequence of event recording: Stores historical records of voltage deviations, excitation faults and protection actions for post-fault traceability and maintenance analysis.
5. Data interaction with upper control systems: Transmit terminal voltage, reactive power, excitation current and alarm status to ABB 800xA, GE Mark VIe and other DCS/turbine control systems via Ethernet or HDLC bus.
6. Auxiliary synchronization logic: Support voltage and reactive power matching before grid connection to simplify generator synchronization operation.

3. Application Scenarios

• Excitation control for medium & small steam turbine generators and mini hydroelectric generators
• Diesel generator sets for factory self-contained power plants and distributed emergency standby power stations
• Synchronous generator voltage regulation for offshore platforms and marine vessels (DNV certified)
• Small gas turbine generator sets, matched with Bently 3500 TSI system and GE Mark VIe control system for complete unit monitoring
• Voltage stabilization for backup power units of commercial buildings and data centers

4. Common Typical Issues & Troubleshooting