GB/T 40595-2021 in English

GB/T40595-2021 is my country's first national standard that comprehensively regulates the primary frequency regulation technology of various types of grid-connected power sources. It unifies the frequency regulation technical requirements for thermal power, hydropower, nuclear power, new energy and energy storage power stations for the first time. The standard innovatively adopts a differentiated indicator system and formulates corresponding parameters for different power supply characteristics. Its technical highlights are mainly reflected in:

• Frequency response dead zone: divided into 0.02Hz-0.1Hz interval according to power supply type
• Dynamic response time: grading requirements ranging from 4s for energy storage power stations to 45s for thermal power units
• Power regulation amplitude: gradient standard ranging from minimum 6% (nuclear power) to maximum 20% (energy storage)

Deep Peak Loading Adaptation of Thermal Power Units

Under the condition of 30% deep peak loading, a 350MW supercritical unit was optimized by The valve control logic of the steam turbine reduces the primary frequency modulation response time from 52s to 41s, meeting the 45s limit required by the standard. The key improvements include:

1. Use feedforward compensation algorithm to eliminate the impact of main steam pressure fluctuations
2. Optimize the sampling period of DEH system to 80ms (standard requirement ≤100ms)
3. Set dynamic limit of power change rate (8%/min→12%/min)

Verification of rapid response of photovoltaic power station

A 200MW photovoltaic power station achieved the following in the ±0.2Hz step test through the pre-set backup capacity solution:

• Lag time 0.8s (standard ≤1s)
• Adjustment time 13.2s (standard ≤15s)
• Use seamless switching technology between MPPT and frequency modulation mode

Compared with DL/T 1235-2013 and other industry standards, GB/T40595-2021's main breakthroughs are reflected in:

The standard proposes for the first time class=instrument>Isolated Grid Operation Special Requirements (Article 4.8) clearly state that when the grid is in isolated operation, the unit must have customized frequency regulation function, which provides a technical basis for special scenarios such as microgrids and island power supply.