Voltage Sag Compensation


The modern power network is frequently disturbed by voltage spike and sag. Over 90% of power quality event can be traced to short duration (less than 1second) voltage event. While this sag is often undetected, it causes direct production loss in critical process operations.

Mun Hean’s Power Quality team has been working with these industry players to detect and solve their voltage sag issues. Critical process operations affected by voltage sag include:

• Semiconductor fabrication
• PLC Controlled automation robot
• Chemical & Petroleum process production
• Dairy, food & beverage production

The root cause of voltage sag originates from Surge Protection Device operation during lightning surge incident on utility high voltage power line. A momentary line to earth short circuit is created during the SPD discharge function which cause the line voltage to fall abruptly. The event duration is short-lived but poses challenges to many critical process operation that depend on a stable voltage.

To solve these problems Mun Hean’s team will perform a study on the client’s operations, prescribe a suitable voltage sag compensation solution with ROI analysis and complete the installation with testing and commissioning. Mun Hean has partnerships with Voltage Sag compensation solutions from Europe with the following core designs:

Static Current Source Buck-Boost Transformer voltage compensator
• Meet ITIC(CBEMA) & SEMI F-47 Power Quality Standard
• 3ms Respond Time
• 3Phase 400VAC Output
• 150kVA to 900kVA
• Maintain Line Output Voltage at 90% when Input falls to 40%
• Suitable for whole plant PQ installation

Super Capacitor Energy Storage voltage compensator
• Meet Samsung Power Vaccine Power Quality Standard
• Instantaneous Respond Time
• 3Phase 400VAC / 1Phase 230VAC / 1Phase 24VDC Output
• 1kVA to 600kVA
• Maintain Line Output Voltage at 100% when Input falls to 0% for duration up to 10seconds
• Suitable for direct feed to critical end loads

These core designs use state-of-the-art power electronics and digital signal processing control to provide a stable voltage level under severe utility side disturbances.