China released the draft power-industry standard Technical Requirements for User-Side Grid-Related Safety (<用户侧涉网安全技术要求>) for public comment on 31 August 2026.
Less than two weeks later, on 11 September, a commercial data-centre UPS completed a wideband impedance scan at the New Energy Research Institute of the China Electric Power Research Institute (CEPRI).
The two developments point in the same direction: for large power-electronic loads, grid-side behaviour is becoming part of the equipment specification.
The draft addresses several areas related to user-side grid safety, including voltage and reactive-power control, oscillation analysis, grid-related protection, testing, and parameter management.
Its scope is important.
The draft applies to large users connected at 35 kV and above that are under dispatch management. Most conventional UPS installations at 400 V, including hospital, commercial and industrial systems, therefore fall outside its direct scope.
However, the technical language used in high-voltage connection studies can still influence EPC specifications and consultant requirements for lower-voltage projects.
Large data centres contain significant amounts of power-electronic equipment, including UPS systems, rectifiers and power supplies.
Huawei Digital Power announced on 11 September 2026 that its UPS5000H had completed a wideband impedance scan at CEPRI's New Energy Research Institute. The company also stated that the UPS5000E had previously completed the same type of test and had been verified in an operating data centre.
The announcement followed a wideband oscillation event reportedly associated with the high-power electronic load of a large data centre in China during 2026.
This shifts part of the discussion from the UPS output to the UPS input.
Traditionally, UPS buyers focus on specifications such as:
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output voltage regulation
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transfer time
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efficiency
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overload capability
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battery runtime
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input THDi
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input power factor
For very large installations, input impedance and the interaction between the UPS and the upstream grid may also become relevant.
The published information does not provide a universal pass threshold, frequency range or rule for applying one test result to sites with different grid short-circuit capacities. Those details should therefore be confirmed before treating an impedance test as a general product specification.
Not directly.
A hospital using a 120 kVA UPS on a 400 V supply, for example, is below the scope defined in the draft standard.
But specifications written by utilities, consultants and EPC contractors often move downstream over time.
A requirement that first appears in a large 35 kV data-centre connection study may later appear as a requested technical parameter on an industrial UPS datasheet.
That is why UPS suppliers and buyers should pay attention even when the regulation itself does not directly apply to their project.
For large or sensitive projects, buyers should look beyond a single efficiency or THDi figure.
Ask at what load level the figure was measured and what rectifier topology was used.
A THDi figure without test conditions is difficult to compare between products.
Many UPS systems spend most of their operating life below full load.
The input power factor at the expected operating load can therefore be more useful than the full-load value alone.
Ask which voltage disturbances the rectifier can ride through and when the UPS transfers to battery operation.
This is different from simply asking whether the UPS has 0 ms transfer time.
For large grid-connected sites, the system designer may require input impedance, harmonic or short-circuit contribution data for connection studies.
The exact requirement should come from the utility, consultant or grid-connection agreement.
UPS input characteristics should be considered together with generators, transformers, breakers and upstream protection settings.
This is especially important where the site operates with a weak grid or frequently transfers to generator power.
The draft Chinese standard does not suddenly create a new requirement for every UPS installation.
Its significance is broader.
As data centres and other large electrical users install more power-electronic equipment, utilities are paying closer attention to how those loads interact with the grid.
For UPS buyers, that means future specifications may increasingly include input-side behaviour rather than focusing only on output performance and battery backup.
TAFENG supplies low-frequency online UPS systems, isolation transformers and supporting battery systems for industrial and medical projects.
For project selection, the site voltage, load characteristics, upstream protection and connection conditions should be reviewed together rather than relying on a generic UPS datasheet alone.
Sources: Draft Technical Requirements for User-Side Grid-Related Safety; China Electric Power Research Institute / industry reports published 11 September 2026; National Energy Administration user-side grid safety documents.
