Power System Studies

UPS and Battery Sizing Study

Right-size the ride-through. Match autonomy to actual restoration time.

Static or rotary UPS. Lithium-ion, VRLA, or flow battery. Five minutes of ride-through or eight hours of autonomy. We size the UPS topology against actual critical load, engineer the battery against discharge profile, and tie it to the standby DG restoration sequence. IEEE 485 and IEC 62040 compliant, signed by a Chartered Engineer.

Why this matters

Why UPS sizing trips on inrush and battery sizing fails on aging

Two systemic errors dominate. The first is sizing the UPS for steady-state critical load and forgetting the inrush of the connected transformer or chiller VSD. The first time the load step hits, the UPS goes to bypass, the load sees raw utility, and the ride-through promise breaks. The second is sizing the battery for first-year capacity and forgetting that VRLA loses 20% capacity over 10 years and Li-ion loses 30% over the same horizon depending on chemistry and ambient. End-of-life autonomy must match the standby DG restoration time, not first-day catalogue capacity. A UPS-battery sizing study engineers both correctly.

Method

How we deliver Load Flow Analysis

CEng MIE India-signed deliverables · LiDAR-powered where applicable · digital twin handover ready · routes to the Power System Studies practice lead within 24 hours.

Critical load audit

Connected and projected critical load catalogued · IT, GMP control, instrumentation, safety. Inrush behaviour mapped. Crest factor, harmonic spectrum, leading vs lagging PF measured at the load.

UPS topology selection

Online double-conversion vs line-interactive vs eco-mode evaluated against IEC 62040-3 classification (VFI/VI/VFD). Static vs rotary compared for >500 kVA loads. N+1, 2N, and distributed redundancy options sized.

Battery chemistry + sizing

Discharge profile authored per actual restoration time (typically 5-30 min for DG-backed, 4-8 hrs for non-DG). Battery sized per IEEE 485 (lead-acid) or IEC 62619 (Li-ion). End-of-life capacity targeted, not catalogue capacity.

Acceptance + commissioning protocol

Full-load acceptance test protocol authored. Step-load test sequence, battery discharge test, transfer time measurement, harmonic injection test. Vendor-neutral · works against any UPS OEM.

Sign-off + lifecycle plan

Report signed by a Chartered Engineer. Battery replacement schedule and capacity-monitoring protocol attached. UPS firmware audit schedule defined.

Standards + compliance

Built to the standards your auditors quote

Reports reference the international and national standards your regulators, F500 audit teams, and corporate process safety leads cite. Every deliverable signed by a Chartered Engineer (CEng MIE India).

IEC 62040 (all parts) · Uninterruptible Power Systems
IEEE 485 · Sizing Lead-Acid Batteries for Stationary Applications
IEEE 1184 · Selecting and Sizing Batteries for Uninterruptible Power Systems
IEC 62619 · Secondary cells and batteries for industrial applications · Safety requirements
NFPA 70 (NEC) Article 480 · Storage Batteries · USA

Anonymous case anchors

What this looks like in production

Three landmark engagements from our verified roster · quantified outcomes, no client names disclosed without written permission.

Data centre, India · Tier III IT load

Sized 6 × 500 kVA online double-conversion in 2N. Li-ion battery sized for 8-minute ride-through to DG restoration. End-of-life capacity verified for 10-year horizon.

Pharma site, USA · cleanroom controls

Inrush analysis caught 3.2× steady-state inrush from HVAC VFDs. Resized UPS from 300 to 500 kVA · prevented Year 1 bypass events that would have failed GMP audit.

Petrochem, UAE · ESD control system

SIL 3 ESD logic UPS sized for 4-hour autonomy without DG. VRLA battery cabinet engineered for hazardous-area Class I Div 2 envelope. Passed third-party functional safety audit.es. Identified 5.8% voltage violation at remote MCC during compressor startup. Recommended on-load tap-changer retrofit.

Frequently asked

Load Flow Analysis · the practical questions

How long does a typical load flow study take?

A standalone load flow on a single 132 kV substation: 3-4 weeks. A full plant-wide study (220 kV down to 415 V) with N-1 contingencies: 6-10 weeks. LiDAR-assisted as-built verification adds 1-2 weeks but de-risks model accuracy.

Can you work with my existing ETAP / DigSILENT model?

Yes. We routinely take over legacy models, audit them against current field reality (via LiDAR), and re-baseline. About 60% of our load flow engagements start from an existing model.

Do you provide the ETAP / DigSILENT software, or do we need a licence?

Both options. We can deliver on our licences and hand over a PDF + DWG report, or we can build in your environment so your team retains the live model. The handover model + report is yours regardless.

What's the link between load flow and your digital twin offering?

The verified network model from a load flow study is the electrical layer of the Wistwin digital twin. We hand it over as a structured model that ingests directly · saving 4-6 months of digital twin foundation work.

Are your reports accepted by international F500 audit teams?

Yes. Our reports are signed by Chartered Engineers (CEng MIE India), reference IEEE / IEC / NFPA / NEMA standards, and have been accepted in audits by Bayer, Pfizer, TATA, Adani, JSW, and others on our verified roster.

Scope your Load Flow Analysis engagement.

Tell us your plant, region, and scope · a named Chartered Engineer responds within 24 hours.

4 fields. No phone interview to start.
Per-discipline routing to the Power System Studies practice lead.
Anonymous case anchors sent with first reply.
Same-day callback for deadline-driven enquiries.

Power System Study Scoping

ETAP/DigSILENT/PSCAD-led · routes to Practice Lead PSS · 24-hour response.