BriPower Announces Delivery of Advanced Broadband Voltage Injection and Impedance Measurement Systems

1. Strategic Announcement & Context

In the contemporary landscape of powersystems engineering, the rapid integration of power electronics-basedgeneration—most notably wind and solar—has introduced complex stabilitychallenges. Accurate broadband impedance measurement is now a prerequisite forcharacterizing the interaction between these converters and the grid tomitigate oscillatory phenomena. In alignment with these requirements, BriPowerhas completed the delivery of a specialized hardware suite to theimplementation site in Nanjing, Jiangsu.

The delivery comprises two core systems:the Broadband Voltage Sequence Component Injection Device and the High-VoltageBroadband Impedance Measurement System. Designed for sophisticated laboratoryenvironments, these systems provide a comprehensive solution for eliciting andcapturing the frequency-dependent response of power converters. The followingsections detail the technical specifications and architectural principles ofthese systems, beginning with the harmonic source required for precise grid perturbation.

2. The Harmonic Source: Precision BroadbandVoltage Injection

Assessing the impedance characteristics ofmodern converters requires the introduction of high-resolution perturbationsacross a broad frequency spectrum. The Broadband Voltage Sequence ComponentInjection Device functions as a precision harmonic source, capable ofsuperimposing positive and negative sequence voltage components onto thefundamental grid frequency. To achieve this, BriPower utilizes two primarytechnical routes: transformer coupling via wide-bandwidth SiC-based linearpower amplifiers or series resonance through adjustable RLC impedance networks.

The device’s technical parameters areengineered for high-power applications:

• Operational Capacity: Maximum working voltage of 1200V (AC) with a main circuit current capacity of up to 3600A.

• Injection Spectrum: A frequency range of 2Hz to 2kHz with a minimum resolution of 0.1Hz. The   system supports granular frequency step sizes: 0.1Hz (2.5Hz–10Hz), 1Hz   (10Hz–100Hz), 10Hz (100Hz–1kHz), and 20Hz (1kHz–2kHz).

• Injection Precision: Harmonic amplitudes are adjustable between 1% and 5% of the rated voltage, with an injection error margin strictly maintained below 0.5%.

A critical architectural feature is thedual-module configuration, consisting of a 0–3600A module and a 0–600A module.These modules can operate independently, allowing for flexible testing acrossdifferent current scales while ensuring that harmonic voltage accuracy remainsconstant across both ranges. This precision in signal injection necessitates anequally sophisticated measurement architecture to capture the resulting systemresponse.

3. Integrated Measurement Architecture:High-Voltage Sensing

Capturing the response elicited by injectedperturbations requires high-fidelity data acquisition, particularly inhigh-voltage environments where signal integrity is easily compromised. TheHigh-Voltage Broadband Impedance Measurement System, positioned on the gridside of the test circuit, provides the necessary sensing resolution to monitorconverter behavior.

The system is defined by the followingtechnical specifications:

• System Rating: Rated for 35kV operation with a measurement range of 0–100A.

• Sensing Methodology: Current acquisition is performed via fiber optic sensors, while voltage signals are collected through capacitive-resistive (R-C) dividers featuring a high-voltage arm capacitance of 300pF (±5%) and a resistance of 70MΩ (±5%).

• Measurement Accuracy: The   system delivers 0.2% accuracy for current (per GB/T 20840.8) and    specialized voltage accuracy tiers: ≤0.5% for AC, ≤0.2% for DC, and ≤3%   for lightning and operation impulses.

• Digital Processing: Both sensing units provide a -3dB bandwidth exceeding 10kHz. Utilizing a sampling rate of ≥50kHz and the FT3 protocol (IEC6080-5-1), the system ensures the high-resolution capture of high-order harmonics and transient responses.

  These high-precision components are vitalfor maintaining the integrity of impedance calculations in converter-dominatedgrids. By minimizing phase and amplitude errors during the acquisition phase,the system provides a reliable data foundation for stability modeling underreal-world grid conditions.

4. Software Capabilities and ComplianceStandards

Standardized testing protocols areessential for the objective evaluation of renewable energy assets. BriPower’simpedance calculation software is specifically designed to meet the rigorous"yardstick" standards of the Chinese market, ensuring compliance forgrid-connected wind and solar installations.

The software framework adheres to thefollowing standards:

• NB/T 11344-2023: Technical specification for impedance characteristic evaluation of PV power stations.

• NB/T 10651-2021: Technical specification for impedance characteristic evaluation of wind farms.

In addition to executing standard automatedscans, the software supports custom voltage sequence injection for advancedresearch. It uniquely allows for the implementation of non-standard algorithms,provided with full formula explanations and comparative analysis againststandard results. Furthermore, the hardware conforms to fundamental safety andstability guidelines, including GB 38755-2019 (Power System Safety andStability) and GB/T 19964-2024 (PV Grid Connection Requirements).

5. Technical Validation and QualityCommitment

BriPower reinforces its technical rigorthrough a two-stage experimental verification process and third-partycertification. To ensure accuracy across the 2Hz–2kHz spectrum, the systemsundergo:

1. Impedance Verification: Testing   against known R, L, and C components at 500 discrete measurement points to    confirm that amplitude and phase errors remain within specified tolerances.

2. Operational Verification: Conducting   full impedance scanning tests on PV or energy storage converters in strict   accordance with NB/T 11344-2023.

The High-Voltage Broadband ImpedanceMeasurement System includes comprehensive testing reports from nationallyrecognized third-party institutions, adhering to GB/T 20840.7 and GB/T 20840.8.