Home
Sieyuan supplied a complete HV AC resonant test system for the Guangzhou Chuting 500 kV project, delivering a 210 MVA resonant test capacity to withstand-test approximately 20 km of 500 kV XLPE cable installed in power tunnels.
500 kV Cable AC Withstand Voltage Testing with Sieyuan HV AC Resonant Test System
Sieyuan Electric provided a complete HV AC resonant test system for the Guangzhou Chuting 500 kV Power Transmission and Transformation Project. The system was deployed for the on-site AC withstand voltage testing of approximately 20 km of 500 kV XLPE cables installed entirely in power tunnels. The solution combined a high-power variable-frequency test power supply with a high-Q test reactor to address the high power demand, temperature rise, and complex site conditions associated with long-distance high-voltage cable testing.
Project Overview
Sieyuan supplied a complete HV AC resonant test system for the Guangzhou Chuting 500 kV project, delivering a 210 MVA resonant test capacity to withstand-test approximately 20 km of 500 kV XLPE cable installed in power tunnels.
Project Background
20 km of 500 kV cable in power tunnels needing high test capacity in a confined space.
Key Challenges
High charging current, sustained-test heat rise, and a confined tunnel installation.
Sieyuan Solution
Single-unit 1,200 kW supply and a high-Q reactor simplify wiring and cut heat loss.
Technical Highlights
210 MVA resonant capacity from a 1,200 kW supply, rated for cable tests up to 100 km.
Project Overview
Project Background
The Guangzhou Chuting 500 kV Power Transmission and Transformation Project involved the installation and commissioning of approximately 20 km of 500 kV XLPE cables in power tunnels. The long cable length resulted in significant capacitive charging current during the AC withstand voltage test, while the tunnel-based installation environment imposed constraints on equipment layout, lifting, and wiring. An HV AC resonant test system with sufficient test capacity and stable long-duration operation was therefore required to support the on-site cable testing process.
Key Challenges
High Power Demand — The long cable length resulted in significant capacitive charging current, placing high requirements on the on-site input power supply and system efficiency.
Temperature Rise During Continuous Testing — Long-duration high-voltage testing required effective control of reactor losses and temperature rise to maintain stable operation.
Complex Site Conditions — The confined tunnel environment required a compact system configuration with simplified wiring, installation, and on-site commissioning.
Sieyuan Solution
Single-Unit High-Power Variable-Frequency Power Supply — Sieyuan adopted a single-unit 1,200 kW variable-frequency test power supply together with a single high-Q test reactor, reducing the required on-site input power and simplifying system coordination.
High-Q, Low-Loss Test Reactor — The high-Q iron-core test reactor reduced power loss and temperature rise during long-duration high-voltage operation, supporting stable testing performance.
Simplified System Configuration — The single-power-supply and single-reactor configuration avoided the need to parallel multiple lower-capacity units, reducing risks associated with uneven current distribution and local overheating while simplifying system wiring and commissioning.
Technical Highlights
1,200 kW Variable-Frequency Test Power Supply — Provides the active input power required to drive the resonant test system.
210 MVA Resonant Test Capacity — The series-resonant system delivers a 210 MVA test capacity from a 1,200 kW active power input.
High-Q Test Reactor — The iron-core test reactor features a quality factor (Q) of ≥ 200, with low power loss and low temperature rise.
Up to 100 km Cable Testing Capability — The system is designed to support cable test lengths of up to 100 km. For the Guangzhou Chuting project, the actual cable test length was approximately 20 km.
