GWZC-9803 Automatic Synchronizing Device (ASD) Introduction

          GWZC-9803 Automatic Synchronizing Device (ASD) ensures seamless generator-grid connection for high-voltage substations (33kV/66kV). Key features include microprocessor-based phase angle calculation, automatic voltage/frequency regulation assistance, and anti-reverse power protection. Equipped with dual communication interfaces and event recording for grid operation analysis.

GWZC-9803 Automatic Synchronizing Device (ASD) Functions and Characteristics​
​
Primary Functions (ANSI Codes):​​

1. Automatic Synchronizing (Frequency and Voltage Control) (ANSI 25)
2. Loop Closing (ANSI 25/79)
3. Dead Line Closing (ANSI 27/79)
4. Circuit Breaker Timing Test (ANSI 39/50BF)

​
Communication Functions:​​

1. Protocols: IEC 61850 (Optional), Modbus, DNP3.0, Ethernet RS485.
2. Interfaces: 2×RJ45 ports for high-speed data exchange (100Mbps), enabling seamless SCADA integration.

​Key Characteristics:​​

1. ​Processing and Memory: 32-bit DSP core with 512KB FRAM (ensures 10-year data retention for fault logs).
2. ​Measurement Accuracy: Monitors |Z|, Φ, I0, V0 with 0.2% precision for reliable fault discrimination.
3. ​Input/Output Flexibility: 7×CT/VT inputs and 10×programmable relays for customizable trip circuits.
4. ​Logic Configuration: LOGIC>EDIT™ graphical editor for easy protection logic programming.
5. ​Trip Circuit: 250V AC/DC rated with seal-in monitoring to prevent nuisance operati ns.
6. ​Time Synchronization: IRIG-B/PPS support (±1μs accuracy) for coordinated event recording.
7. ​Anti-Maloperation: Adaptive TV algorithm filters noise to avoid false triggering.
8. ​Communication: Dual Ethernet and fiber interfaces for redundant connectivity.
9. ​Data Recording: 32-cycle COMTRADE waveform capture for detailed fault analysis.
10. ​Low Power Design: <5W operation (compatible with 24-220V DC/AC supplies).
11. ​EMC Robustness: Class IV certification (IEC 60255-26) for electromagnetic compatibility.
12. ​Environmental Tolerance: Operates from -40°C to +85°C, ensuring reliability in extreme conditions.

GWZC-9803 Automatic Synchronizing Device (ASD) Working Principle​

          The GWZC-9803 ASD automatically synchronizes a generator or power source with a running bus (grid) to enable safe, smooth connection by ensuring key parameters meet predefined thresholds before closing the circuit breaker.

​Core Synchronization Conditions​

The device verifies three critical factors:

1. ​Voltage Match: The generator voltage (Ug) and bus voltage (Ub) must differ by ≤±5% (adjustable).
2. ​Frequency Match: The frequency difference (Δf = fg – fb, where fg is generator frequency, fb is bus frequency) must be minimal (typically 0.1–0.5 Hz) to avoid mechanical stress.
3. ​Phase Angle Match: The phase difference (Δθ) between Ug and Ub must be within ±10° (adjustable) to prevent surges.
4. Additionally, it checks that the generator and bus share the same phase sequence (e.g., ABC) to avoid short circuits.

Working Process​

1. ​Real-Time Monitoring: The ASD continuously measures Ug, Ub, fg, fb, and phase angles.
2. ​Parameter Adjustment (if needed)​: If conditions are unmet, it sends signals to the generator’s governor (to adjust speed/frequency) and AVR (to adjust voltage) until values fall within limits.
3. ​Optimal Timing Calculation: It predicts the ideal breaker-closing moment—typically when Δθ ≈ 0° (or a slight lead/lag) to minimize transient impacts.
4. ​Breaker Closure: Once all parameters (ΔU, Δf, Δθ) are within safe ranges, the ASD triggers the circuit breaker at the optimal instant.
5. ​Protection: If abnormal conditions (e.g., excessive slip, voltage spikes) arise, it aborts synchronization to prevent damage.

Operation Modes​

1. ​Manual: Operators initiate sync based on ASD-displayed data.
2. Automatic: The device fully automates the process without manual input.

Electrical Specifications​

​Power Supply:​​

● AC: 85-264V, 47-63Hz (≤15% THD)
● DC: 100-370V (≤5% ripple)

​Rated AC Parameters:​​

● Voltage: 100V/√3 or 100V
● Current: 5A/1A
● Frequency: 50Hz

​Overload Capacity:​​

● Current Circuit: 2×In continuous | 10×In (10s) | 40×In (1s)
● Voltage Circuit: 1.5×Un continuous

​Power Consumption:​​

● Supply: <10W (static), ≤15W (trip)
● Current Circuit: ≤1VA/phase (5A) / ≤0.5VA/phase (1A)
● Voltage Circuit: ≤0.5VA/phase

​Digital Output:​​

● Dry contact (8A@250VAC / 30VDC)
● Dielectric: 4kVAC (coil-contact), 1kVAC (open contact)
● Operating Time: 5ms (typ) / 8ms (max)
● Mechanical Life: 100k operations

​Protection Performance​

​Operating Range:​​

● Voltage: 0.5-120V (phase)
● Current: 0.02-20×In
● Zero-Seq Current: 0.05-20A
● Frequency: 35-65Hz | Delay: 0-100s

​Accuracy:​​

● Voltage/Current: ±2.5% or ±0.1V/±0.05A (whichever greater)
● Frequency: ±0.01Hz
● Settings: ±2.5%

​Trip Time:​​

● Instantaneous: ≤35ms (≥1.2× setting)
● Time-Delayed: ≤1% of setting or 35ms

​Measurement & Monitoring​

​Range:​​

● Voltage: 0.5-120V | Current: 0.02-1.2×In

​Accuracy:​​

● V/I: ±0.2% | Frequency: ±0.01Hz | Other: 0.5%
● Time Sync: ≤2ms | SOE: ≤1ms

​Event Recording:​​

● 128 protection trips/operations
● 32 self-tests/fault waveforms (COMTRADE)

​Environmental & Mechanical​

​Operating Temp:​​

● Standard: -10°C to +55°C
● Extended: -40°C to +70°C*

​Storage Temp:​​ -40°C to +80°C
​Humidity:​​ 5-90% RH (non-condensing)
​Pressure:​​ 60-110 kPa
​Compliance:​​

● IEC 60255-21 (vibration/shock)
● IEC 61000-6 (EMC)