# Microgrid energy storage PCS Bidirectional PCS for converting power between battery DC and microgrid AC systems, with grid-connected and islanded configurations selected to match the project. What does a microgrid PCS do? A microgrid power conversion system (PCS) is the bidirectional interface between a battery’s DC bus and the site’s AC bus. It converts DC to AC when the battery supplies loads, and AC to DC when the battery charges. A PCS can also coordinate power exchange with PV, the utility grid, a diesel generator and an energy management system (EMS), when those interfaces are included in the selected system design. How does PCS operation differ on-grid and off-grid? Grid-connected operation When connected to a stable utility grid, the PCS synchronizes with the AC bus and follows configured active- and reactive-power commands. It can charge the battery from the grid or discharge to support site loads, subject to the PCS rating, EMS settings, interconnection approval and local regulations. Islanded and weak-grid operation During islanded operation, a grid-forming PCS establishes or supports the local AC voltage and frequency. Battery power responds to the difference between generation and load; PV and generator coordination, transfer equipment, protection and load-step capability must be engineered for the project. Not every PCS model supports every mode, so check each product’s stated functions and interface diagram. Compare VGRID PCS and hybrid equipment VGRID’s product families include the SP125HCPS microgrid PCS, the wall-mounted LEONA-H135K, 250 kW and 375/500 kW hybrid cabinets, and the 750 kW PCS cabinet. The LEONA-H135K brochure lists 135 kVA rated off-grid output; confirm the approved datasheet for its active-power rating. The 1 MW, 1.5 MW and 2 MW options are project solutions formed by parallel equipment, not single-unit model ratings. The 200 kW LEONA-M200K is a PV MPPT DC/DC controller, not a PCS. [SP125HCPS microgrid PCS](/en/product/sp125hcps)[LEONA-H135K wall-mounted PCS](/en/product/leona-h135k)[250 kW hybrid cabinet](/en/product/sp250hag2t)[375/500 kW hybrid cabinet](/en/product/sp375-500hag2)[750 kW PCS cabinet](/en/product/sp750h54pstd-2)[1 MW–2 MW parallel PCS solutions](/en/blog/mw-scale-parallel-pcs-solutions) How to select a PCS Compare continuous active power (kW) and apparent power (kVA), DC battery-voltage window, charge/discharge current, grid-forming functions, PV and generator interfaces, transfer arrangement, overload capability, parallel limits and certifications. Share the battery datasheet, load profile, PV design and single-line diagram so VGRID can confirm the configuration. PCS frequently asked questions What does a microgrid PCS do?It converts power bidirectionally between a battery DC bus and an AC microgrid bus: DC-to-AC for discharge and AC-to-DC for charging. Interfaces and operating functions depend on the selected model and project configuration. How does a PCS operate in grid-connected and off-grid modes?On-grid, it synchronizes to the utility and follows configured active/reactive power commands. In islanded mode, a grid-forming model establishes or supports AC voltage and frequency while coordinating battery power with PV, generators and loads. Confirm each model’s supported modes and transfer design. What VGRID PCS power ranges are available?The current families include SP125HCPS, LEONA-H135K, 250 kW, 375/500 kW and 750 kW equipment. The H135K brochure states 135 kVA rated off-grid output; verify its active kW rating. 1 MW, 1.5 MW and 2 MW are parallel-system solution sizes subject to engineering. What is the difference between a PCS and a PV MPPT DC/DC controller?A PCS converts power between battery DC and AC buses. A PV MPPT DC/DC controller tracks the PV array’s maximum power point and converts PV-side DC; it is a different device. LEONA-M200K is a PV MPPT DC/DC controller. What should I provide to select a bidirectional PCS?Provide battery voltage and BMS details, continuous and peak load profile, grid conditions, PV array data, generator information, transfer requirements and a single-line diagram. These determine the PCS power, interfaces, protection and parallel configuration. ## SP125HCPS Series Microgrid Energy Storage PCS - SKU: SP125HCPS - MOQ: 1 set - URL: https://www.vgridpower.cn/en/product/sp125hcps The SP125HCPS Series Microgrid Energy Storage PCS is a high-efficiency, high-reliability energy storage converter developed for small and medium-sized energy storage microgrids. It supports DC/AC coupling, offers an optional model with a built-in STS, achieves grid-connected/off-grid switching time of <10 ms, and a maximum efficiency of 98.5%.