In the pharmaceutical industry, precision, stability, and uninterrupted operations are non-negotiable. Yet, when it comes to electrical design, many facilities still underestimate the critical role of Load Flow Studies.

Let’s walk through a real case from a pharma manufacturing plant where skipping proper load flow analysis led to multiple operational issues – all of which could have been avoided with a structured power system study.

The Scenario: Mid-Sized Injectable Pharma Plant – Gujarat

• Total Installed Load: 2.5 MW
• Power Sources: 11 kV Utility Supply + 500 kVA DG Backup
• Critical Loads: Cleanroom AHUs, Compressors, Water Purification, Packaging Lines
• Key Issue: No formal load flow analysis during design stage

Issue 1: Voltage Drop in Cleanroom AHU Panels

Post-commissioning, maintenance teams observed low voltage alarms and VFD tripping in cleanroom AHUs during peak production.

Diagnosis:

• Voltage at the panel dropped to 374 V during full load
• Long cable runs (~150m) from the main LT panel
• Cable sizing was based only on current-carrying capacity, not voltage regulation

Solution:

• Load flow study revealed a 7.5% voltage drop
• Cable upgraded from 3.5C x 120 sq.mm to 3.5C x 185 sq.mm
• Transformer tap changed from 1.0 pu to 1.05 pu to compensate line loss

Issue 2: Underutilized DG and Lack of Switching Logic

During utility failures, only 25% of the plant load shifted to DG. However, the DG operated under-loaded (~20%), leading to frequent carbon deposit issues and heating.

Diagnosis:

• No minimum load scenario was considered in the initial design
• Auto-load changeover logic was not optimized
• No sequencing for non-critical loads during DG operation

Solution:

• Load flow study modeled emergency load shedding and addition
• Re-grouped load feeders: assigned purified water system, chillers, and select lights to DG
• Adjusted DG loading to ~65% for stable operation

Issue 3: Neutral Overheating Due to Unbalanced Phases

Thermal scanning showed excessive heating in the main panel’s neutral bar – later linked to unbalanced phases.

Diagnosis:

• Load flow model showed >25% imbalance between R and B phases
• HVAC and clean utility loads were concentrated on a single phase
• No phase-wise load mapping during electrical layout design

Solution:

• Redistributed feeders across phases for <10% imbalance
• Added real-time monitoring for phase-wise loading
• Recommended installation of automatic phase correction (optional) 

Summary: Before vs After Load Flow Optimization

Why Load Flow Studies Matter in Pharma Facilities

Pharmaceutical plants have a unique load profile – sensitive equipment, HVAC systems, automated lines, and stringent uptime requirements. Poorly distributed or under-analyzed load systems can lead to:

• Product batch rejection due to temperature/humidity variation
• Loss of equipment life due to voltage sag
• Unstable DG performance during audits or emergencies
• Increased fire risk from overloaded cables or neutrals

Key Load Flow Scenarios You Must Study

1. Normal Load Case: Full production + utility source
2. Minimum Load Case: Validation/maintenance shift
3. Emergency Case: DG running with only critical loads
4. Expansion Case: With additional cleanroom or HVAC loads
5. Reactive Power Scenario: To optimize capacitor placement

Tools We Use

At Elegrow Technology, we use advanced simulation tools like ETAP and DIgSILENT to build detailed single-line models, simulate every operating condition, and provide actionable insights for cable sizing, voltage regulation, transformer tap settings, and more.