Description
ABB UNITROL 1020 3BHE030579R0007 Digital Automatic Voltage Regulator (AVR)
Brand: ABB | Model: UNITROL 1020 | Part Number: 3BHE030579R0007 | Product Category: Digital Automatic Voltage Regulator (AVR)
Developed by ABB as a high-performance digital automatic voltage regulator (AVR), the UNITROL 1020 (3BHE030579R0007) is a core component of synchronous generator excitation systems, specifically designed for small and medium-sized synchronous generators with a typical capacity of 100 kVA to 20 MVA. It maintains the generator terminal voltage at a set value by real-time adjusting the rotor excitation current, integrates advanced digital control technology and comprehensive protection functions, and is widely used in hydropower, gas turbines, diesel generator sets, combined heat and power (CHP) and industrial captive power plants. With high voltage regulation precision, fast dynamic response and compact design, this AVR effectively improves the stability of generator grid connection and the quality of electrical energy.
Product Overview
The ABB UNITROL 1020 3BHE030579R0007 is a compact digital automatic voltage regulator belonging to ABB’s UNITROL 1000 series, which combines 32-bit microprocessor technology, full digital control algorithms and robust structural design. As the core control unit of the generator excitation system, it is responsible for automatic voltage regulation, reactive power control, and dynamic performance optimization, ensuring the stable operation of the generator under various working conditions. This AVR supports IEEE standard excitation models (such as ST1A, AC1A), which is convenient for system simulation and parameter tuning. Its compact structure (only 120 mm wide) allows direct installation on standard DIN rails, making it particularly suitable for renovation projects or OEM complete sets of equipment with limited space. It is equipped with a local LCD display and buttons for on-site operation, and supports remote monitoring and data acquisition through communication interfaces, achieving a perfect balance between reliability, ease of use and performance.
UNITROL 1020 3BHE030579R0007
Product Highlights
- High-Precision Voltage Control: Adopts full digital control algorithm, with a steady-state voltage accuracy of ±0.5% under rated working conditions, which is far superior to traditional analog AVR. It can effectively suppress voltage fluctuations, ensure the stability of generator output voltage, and meet the strict grid-connection requirements of power grid companies for distributed power sources.
- Fast Dynamic Response: The step response time is less than 100 ms, and the overshoot is less than 5%. It can quickly respond to load changes (such as the start of large motors), suppress voltage drop, protect sensitive electrical equipment, and ensure the stable operation of the power generation system during sudden load changes.
- Comprehensive Protection & Stability Enhancement: Built-in complete protection mechanisms, including overexcitation limit (OEL), underexcitation limit (UEL), V/Hz limit, and PT disconnection detection. The optional Power System Stabilizer (PSS) can inject additional damping signals to suppress 0.1–2 Hz power oscillation, improve transmission limits, and enhance the stability of the power system. OEL prevents rotor overheating, UEL avoids static stability loss of step, and V/Hz limit protects the stator core from magnetic saturation damage during start-up and shutdown stages.
- Flexible Communication & Remote Monitoring: Equipped with RS-485 interface (supporting Modbus RTU protocol), and optional Ethernet and USB interfaces, it can seamlessly connect to SCADA, DCS or energy management systems. It supports remote reading of key data such as voltage, current, reactive power and alarm status, realizing remote monitoring, parameter configuration and fault diagnosis, which is convenient for predictive maintenancesuperscript:3.
- Easy Installation & Commissioning: Adopts 35 mm DIN rail installation design with IP20 protection level, which is compact and easy to install in industrial control cabinets. It supports auto-tuning function. Engineers only need to input the generator rated voltage, frequency and excitation peak value, and the AVR can automatically calculate PID parameters, greatly shortening the commissioning cycle. The local 4-digit LED display and 4 buttons allow real-time viewing of key variables without external instruments.
- Strong Environmental Adaptability: Made of high-quality industrial-grade components, with robust mechanical design and strong anti-electromagnetic interference capability. It can operate stably in an operating temperature range of -25℃ to +70℃ and a relative humidity of 5% to 95% (non-condensing), adapting to harsh industrial on-site environments such as vibration and temperature changessuperscript:3.
- Dual-Channel & Parallel Operation Capability: Supports dual-channel control, built-in advanced load sharing function for parallel operation of multiple generators, and has rotating diode monitoring and automatic synchronization capabilities, which enhances the reliability of the system in parallel operation scenariossuperscript:4>.
Technical Specifications
| Parameter | Details |
| Model | ABB UNITROL 1020 |
| Part Number | 3BHE030579R0007 |
| Product Type | Digital Automatic Voltage Regulator (AVR) |
| Applicable Generator Capacity | 100 kVA – 20 MVA (typical) |
| Processor | 32-bit microprocessor |
| Control Algorithm | Two-channel PID + optional PSS (Power System Stabilizer) |
| Steady-State Voltage Accuracy | ±0.5% (under rated working conditions) |
| Dynamic Response | Step response time < 100 ms, overshoot < 5% |
| Voltage Measurement Input | 3-phase AC 100 V (line voltage), 50/60 Hz |
| Excitation Output Control | 0–10 V DC or 4–20 mA (driving external SCR/IGBT excitation power unit) |
| Communication Interfaces | RS-485 (Modbus RTU), optional Ethernet, USB |
| Protection Functions | Overexcitation limit (OEL), underexcitation limit (UEL), V/Hz limit, PT disconnection detection |
| Human-Machine Interface | 4-digit LED + 4 buttons (displaying voltage, reactive power, fault codes) |
| Installation Method | 35 mm DIN rail installation |
| Protection Rating | IP20 (standard), IP54 (optional) |
| Operating Temperature | -25℃ to +70℃ |
| Storage Temperature | -40℃ to +85℃ |
| Humidity Range | 5% to 95% non-condensing |
| Certifications | CE, IEC 60034-16, IEEE 421.5, UL 508 |
UNITROL 1020 3BHE030579R0007
Application Scenarios
The ABB UNITROL 1020 3BHE030579R0007 digital automatic voltage regulator is widely used in various power generation scenarios that require stable voltage control and high reliability, especially suitable for small and medium-sized synchronous generators and industrial power supply systems:
- Hydropower Industry: Applied in small and medium-sized hydropower plants, used to control the excitation system of hydropower generators, maintain stable output voltage, adapt to the fluctuation of water flow and load, and ensure the efficient and stable operation of hydropower units.
- Thermal Power & Gas Turbine Power Generation: Suitable for gas turbine power plants and combined heat and power (CHP) projects, it can quickly respond to the load changes of gas turbines, ensure the stability of generator voltage, and improve the quality of electrical energy and the efficiency of power generation systems.
- Diesel Generator Sets: Used in diesel generator sets for industrial backup power, emergency power supply and field power supply, it ensures that the generator can output stable voltage when the grid is cut off, providing reliable power support for critical loads such as manufacturing lines and pump stations.
- Industrial Captive Power Plants: Applied in industrial captive power plants of steel, chemical, non-ferrous metal and other industries, it controls the excitation system of self-provided generators, realizes stable voltage regulation and reactive power control, and meets the power demand of industrial production.
- Other Fields: Also widely used in marine electrical propulsion and auxiliary power supply, diesel-electric locomotives, direct-connected synchronous wind power generators and synchronous motors, providing reliable excitation control support for various power supply scenarios.
Why Choose ABB UNITROL 1020 3BHE030579R0007?
As a world-leading provider of industrial automation and power solutions, ABB has decades of experience in the research and development of power electronic equipment and excitation control systems. The UNITROL 1020 3BHE030579R0007 inherits ABB’s strict quality control standards and advanced technology, with the advantages of high precision, fast response and easy operation. Compared with ordinary AVR products, it has higher voltage regulation accuracy and more comprehensive protection functions, which can effectively avoid equipment damage caused by overexcitation, underexcitation and other faults. Its compact design and DIN rail installation method are convenient for renovation and upgrading projects, and the auto-tuning function and remote monitoring capability greatly reduce the difficulty of commissioning and maintenance. Complying with global grid codes and industrial standards, it has a long product lifecycle and professional after-sales support, providing a reliable guarantee for the stable operation of your power generation system, and becoming the preferred choice for small and medium-sized generator excitation control projects.
Packaging & Shipping
- Package Included: 1 × ABB UNITROL 1020 Digital Automatic Voltage Regulator (3BHE030579R0007), 1 × User Manual, 1 × Calibration Certificate (Software license not included, available for separate purchase).
- Packaging: Industrial-grade shockproof and moisture-proof packaging, with independent foam cushioning to avoid damage during transportation, ensuring the product arrives in perfect condition.
- Shipping: Global delivery, with tracking number provided after shipment; professional logistics team ensures safe and fast delivery, complying with international transportation standards for industrial electronic components.
