Power Quality Solutions for Hospitals and Medical Facilities
Hospitals rely on MRI systems, CT scanners, X-ray machines, ultrasound equipment, UPS systems and other sensitive electrical loads. Harmonic distortion, voltage fluctuation, rapid reactive power changes and phase imbalance can affect equipment stability, imaging quality and the reliability of critical medical operations.
As a professional Power Quality Solution Provider & Equipment Supplier, SinaVa Power provides integrated hospital power quality solutions combining Active Harmonic Filters, Static Var Generators, capacitor banks and power quality monitoring equipment.
From power quality measurement and system analysis to equipment selection, installation guidance and commissioning support, we help hospitals build safer, more stable and more efficient electrical systems.
Project Overview
Queen Mary Hospital of Hong Kong was established in 1937 and is located in the southwest of Hong Kong Island. It currently has over 1700 beds and offers various specialties and departments, including 24-hour emergency treatment and rehabilitation. Queen Mary Hospital is also a teaching hospital of the Lee-Ka shing School of Medicine at the University of Hong Kong, providing teaching and training facilities for students and graduates in medicine, dentistry, and nursing. Over the years, it has established a good image in the minds of Hong Kong citizens and is a trusted medical institution for most Hong Kong citizens.
SINAVA POWER, as the supplier and contractor for the power quality system of the hospital's electric facility renovation project, has been carrying out targeted line renovation and technical renovation plans for multiple distribution rooms to the hospital since 2022. In the power quality management project at Queen Mary Hospital, there are many imaging medical equipment such as ultrasound, MRI and CT machines, X-ray machines, and DSA (cardiovascular angiography) are used. The MRI generates radio frequency pulses and alternating magnetic fields to generate nuclear magnetic resonance, and both radio frequency pulses and alternating magnetic fields can cause harmonic pollution; The rectifier bridge of the high-voltage rectifier in the X-ray machine will generate significant harmonics during operation, and the X-ray machine is an instantaneous load with a voltage of several tens of Kilo Volts during operation. The primary side of the transformer will increase the instantaneous load by 60-70 kW, which will also increase the harmonics of the power grid. These harmonics will greatly reduce the failure rate of electronic components in the above-mentioned imaging medical equipment, such as causing the monitoring computer to crash and some devices to malfunction, thereby affecting the normal performance of these precision and sensitive instruments and equipment. Not only will the power quality of its self powered circuit decrease, but the transformer that supplies power for a long time will also be affected by it. Usually, CT machines generate the THDi rate of up to 30% during operation, while MRI has the THDi rate of around 20%. Therefore, in response to the characteristics of this industry and the load situation of Queen Mary Hospital's imaging medical equipment, SINAVA POWER has provided a technical solution for power quality control with a total capacity of 4700A in rating at 150A wall mounted harmonic filter and rating at 200A floor stand cabinet respectively to ensure that the THDi in the power system can be maintained below 5%.
Besides the harmonic pollution, another issue faced by medical are industry is voltage stability so do the Queen Mary Hospital. This includes short-term voltage deviation, frequency instability, transient and flicker, all of which can interfere with the operation of medical equipment and affect the imaging quality of medical devices, such as ultrasound examinations. Therefore, our chartered civil engineer has conducted professional analysis and determined to provide a reactive power compensation scheme of 1450kVar for the project. Unlike typical electronic capacitor reactive power compensation schemes, this scheme fully utilizes SVG/Static Var Generator technology using 3-level topology circuits. Due to the tendency of imaging medical equipment to generate peak currents during operation, and the working principle of the equipment, it is particularly prone to voltage spikes and flicker lasting for a few milliseconds(ms). This requires compensation equipment to not only provide stable reactive power compensation for the power system, but also provide fast response voltage stabilization function. Traditional power capacitors, which use thyristor switching system, a mature compensation control technology, are easy to operate and maintain, and can effectively solve the common reactive power compensation problem in power systems at a lower cost. However, the thyristor switching control switch can only compensate for reactive power in the system with a relatively fixed step size, and cannot make precise adjustments in a short time according to the dynamic changes in reactive power compensation capacity in the circuit. Moreover, the response time of the thyristor is about 20ms, while the IGBT switching time controlled by the PWM circuit is normally within 10us. This enables the SVG controlled by IBGT as the switching unit to effectively meet the voltage stabilization and precise compensation needs of the medical industry. SINAVA POWER has provided an SVG reactive power compensation and stabilization solution with a total capacity of 1100kVar Wall mounted SVG module in the rating of 100kVar and 75kVar respectively for this project to solve the power quality issues such as voltage surges, three-phase imbalances, and rapid flicker caused by medical equipment.
The above reactive power compensation and harmonic filtering solutions, as a comprehensive power quality technology solution, have effectively solved the common problem of imaging medical equipment for Queen Mary Hospital, make this excellent hospital can serve the Hong Kong citizen with high standard of qualification.
Which Power Quality Equipment Does a Hospital Need?
| Power Quality Problem | Recommended Equipment | Primary Function |
|---|---|---|
| High current harmonics | Active Harmonic Filter | Dynamically filters harmonic current |
| Rapid reactive power changes | Static Var Generator | Fast and precise reactive power compensation |
| Stable low power factor | Capacitor Bank | Cost-effective stepped compensation |
| Harmonics and reactive power together | AHF + SVG Hybrid Solution | Combined harmonic and power factor control |
| Voltage or phase imbalance | SVG or AHF | Dynamic balancing and compensation |
| Unknown disturbance source | Power Quality Analyzer | Measurement, diagnosis and event recording |
The final equipment capacity should be selected according to actual harmonic measurements, transformer capacity, load profile, system voltage and future expansion requirements.
Need a Power Quality Solution for Your Hospital?
Harmonic distortion, unstable power factor and voltage fluctuation can affect sensitive medical equipment and increase stress on the hospital distribution system.
As an experienced Power Quality Solution Provider & Equipment Supplier, SinaVa Power can evaluate your electrical data and recommend an integrated solution using AHF, SVG, capacitor banks and power quality monitoring equipment.
Send us your single-line diagram, transformer capacity, load list or power quality measurement report to receive:
Preliminary power quality assessment
AHF and SVG capacity recommendation
Equipment configuration proposal
Installation layout advice
Technical and commercial quotation
Send Your Power Quality Report
FAQ-Hospital Power Quality Solutions
What causes harmonic distortion in hospitals?
Hospital harmonics are commonly generated by MRI systems, CT scanners, X-ray machines, UPS systems, variable-frequency drives, LED lighting and other electronic loads that draw nonlinear current.
Why are Active Harmonic Filters used in hospitals?
An Active Harmonic Filter dynamically measures harmonic current and injects an opposite compensation current. It is suitable for hospital loads that vary during different operating conditions.
What is the difference between an AHF and an SVG?
An AHF is primarily used for harmonic mitigation, while an SVG mainly provides fast reactive power compensation, power factor correction and voltage support. Hospitals facing both problems may require a combined AHF and SVG solution.
How is the required AHF capacity calculated?
AHF capacity should be based on measured harmonic current, load diversity, transformer capacity, harmonic spectrum, neutral current and planned equipment expansion. Selecting capacity only according to total load power may result in over-sizing or under-sizing.
Can the system be installed in an operating hospital?
In many cases, equipment can be integrated into an existing low-voltage distribution system. However, the installation location, shutdown window, protection coordination, cable routing and commissioning procedure must be evaluated for each project.
Does SinaVa Power provide customized hospital solutions?
Yes. SinaVa Power provides power quality analysis, equipment selection, customized cabinet configurations, technical documentation and project support based on the hospital’s electrical system and load conditions. The company’s AHF and SVG product pages also describe modular and customizable configurations
