GoodWe says solar and storage plants must increasingly support voltage, frequency and grid stability as inverter-based generation expands
The presented portfolio includes 250 kW and 350 kW PV string inverters, a 215 kW string PCS and medium-voltage stations rated from 3.5 MVA to 9 MVA
The company groups the PCS’s grid-forming capabilities into 6 functions, while validation and certification requirements continue to differ between markets
Solar and energy storage plants will need to provide more support to the electricity grid as inverter-based resources replace conventional synchronous generation. Speaking at the TaiyangNews Solar Power Plants & Storage Conference 2026, Dimitris Pantoulas, Technical Director for Utility Projects Europe at GoodWe, said inverters traditionally converted DC electricity and fed it into an established grid. Replacing conventional generators reduces the grid’s physical inertia, making frequency changes faster and more difficult to control. Renewable power plants must therefore increasingly support voltage and frequency, remain stable under weak-grid conditions and coordinate equipment at the plant level.
He added that individual product capability does not guarantee plant performance. Inverters, power conversion systems (PCS), plant controllers, energy storage and protection equipment must operate together. GoodWe’s Utility Business Unit supports this integration from system design and equipment configuration to commissioning, grid connection and long-term operation.
For utility-scale PV plants, Pantoulas presented the 1,500 V UT Series string inverter, available in 250 kW and 350 kW outputs. The inverter converts DC electricity from the PV modules into AC electricity for the grid. GoodWe specifies a maximum conversion efficiency of 99.01%. It supports up to 30 module-string inputs, with 15 independent maximum power point trackers (MPPTs) to optimize their output. It supports full-power operation at temperatures above 40°C, depending on the model and operating conditions.
After the UT inverters convert the PV array’s DC electricity into AC, GoodWe’s medium-voltage station collects their output and raises the voltage for connection to the medium-voltage grid. The station is housed in a 20-foot container and is available in 3.5 MVA, 5 MVA, 7 MVA, and 9 MVA ratings.
For utility-scale battery storage, Pantoulas presented GoodWe’s 215 kW GW215K-PCS-G10 string PCS. Unlike a PV inverter, which receives DC electricity from solar modules, the PCS manages bidirectional electricity flow between the battery and the AC grid. It converts AC electricity into DC when charging the battery and DC electricity into AC when discharging it.
The 1,500 V PCS also manages reactive power to support the grid and responds to commands from the plant controller or energy management system. The company specifies a maximum efficiency of 98.8% and says the PCS can operate continuously at up to 110% of its rated power. The company also claims operation at a short-circuit ratio (SCR) of 1.0, indicating compatibility with very weak-grid conditions.
GoodWe can combine multiple PCS units with a step-up transformer and an optional sulfur hexafluoride-free ring main unit for medium-voltage switching and protection at up to 24 kV. This factory-integrated arrangement, called the Integrated Conversion System, connects the battery storage system to the medium-voltage grid. According to the company, it reduces the equipment that must be connected and assembled on site.
Speaking about grid-forming control, he explained that a grid-following converter depends on the voltage and frequency already established by the grid. A grid-forming converter establishes its own voltage, frequency and phase reference and can respond independently when grid conditions change. This allows it to support weak grids and contribute directly to voltage and frequency stability. Both control approaches will continue to be used, depending on grid conditions, the available energy source and project requirements, he added.
GoodWe applies this grid-forming control to the GW215K-PCS-G10 introduced earlier. The PCS uses virtual synchronous generator control to reproduce some of the characteristics of conventional synchronous generators. GoodWe groups these capabilities into 6 functions. They cover voltage and frequency support, virtual inertia, active and reactive power response, oscillation damping, fault support, and black-start and islanded operation. According to GoodWe, up to 24 PCS units can operate in parallel in islanded mode with sufficient stored energy, suitable protection and coordinated plant controls.
Beyond the technology itself, Pantoulas said grid-forming is increasingly becoming a regulatory and compliance issue. Although the main capabilities are converging across China and major European markets, performance parameters, testing methods, modeling requirements and certification pathways still differ.
China has introduced a framework for grid-connected storage converters, while Germany, Spain, Italy and Great Britain have developed or are preparing their own technical and testing requirements. Black-start and islanding requirements are also not applied consistently. GoodWe says it has tested these and the other core grid-forming functions of its PCS, but country-specific validation and certification are still required.
Pantoulas concluded that wider grid-forming deployment will require cooperation among equipment suppliers, grid operators, project developers, engineering, procurement and construction companies, and certification bodies.
Watch the full presentation here
