So, how should PCS Fault Ride-Through testing be conducted?

Before starting the test, it is essential to clarify the applicable standards. In China, the following national standards are mainly used:

• Test Procedures for Grid Connection of Electrochemical Energy Storage Stations (GB/T 36548-2024):
  Specifies grid performance testing methods, including fault ride-through.
• Technical Specification for Testing of Energy Storage Converters (GB/T 34133-2023):
  A standard specifically focused on PCS testing.

Next, a test platform needs to be established. Taking a typical electrochemical energy storage system architecture as an example, during PCS testing:

• The DC side is powered by a battery simulator (BSS2000 + IT6000C)
• The AC side is connected to a grid simulator (IT7900 / IT7900P)

Next comes the specific testing procedure:

1) Set Test Conditions:
According to the standard requirements, configure different types of voltage fault scenarios. Taking Low Voltage Ride-Through (LVRT) as an example, the key parameters include:

• Fault type:
  Three-phase short circuit (symmetrical) or single-/two-phase short circuit (asymmetrical)
• Voltage sag depth:
  Typically tested at 20%, 50%, and 80% of the rated voltage
• Duration:
  Such as 150 ms, 625 ms, or up to 3 seconds
• Test point:
  Usually conducted at the rated power operating point of the PCS

3) Data Analysis and Evaluation:
After the test is completed, the collected data must be analyzed and compared against the standards to determine compliance. The key evaluation criteria include:

• Continuous operation capability:
  Whether the PCS remains connected to the grid throughout the fault and recovery process without tripping
• Reactive power support capability:
  Whether the PCS can quickly inject the required reactive current, based on the voltage sag depth, to support grid voltage recovery during the fault
• Active power recovery performance:
  Whether the PCS can smoothly and rapidly restore its active power output to the reference value after the fault is cleared

In summary, PCS fault ride-through testing is a standards-driven process that requires a complex and highly precise test setup. The core lies in using a grid simulator to safely and repeatably reproduce various grid fault conditions in a laboratory environment, thereby comprehensively validating the PCS’s fault tolerance and grid-support capabilities.

Therefore, selecting a high-performance grid simulator is key to improving testing efficiency. The ITECH IT7900/IT7900E series grid simulators, with their powerful arbitrary waveform generation capabilities, can simulate a wide range of grid disturbance waveforms, making them an ideal choice for both testing and R&D laboratories.