In 2013 we were recommended to TJ Consult for our Northland project. They have been our preferred consultant since then.
Throughout the years, both Toshi and Jason have provided valuable advice to the PappaRich team. They spent a considerable of time to gain a deep understanding of our business before they came with a customised recommended approach.
Their specialisation in Mechanical, Electrical and Hydraulic has also enabled our team to negotiate more effectively when it comes to leasing. I will strongly recommend them if you are looking for a right partner to work with!”Jian Hui Lee - General Manager at PapaRich
INNERMODE had the opportunity to work on a number of fitout projects with TJ Engineers including the CBD consolidation project for the Department of Transport Planning and Local Infrastructure at 1 Spring Street, Melbourne. The project involves refitting 7,000 sqm. over 6 Floors with a budget of $5 million.
Toshihiko and Jason responded to the design brief professionally by conducted thorough quantitative review and audit of the existing building services. The services documents and specifications are well detailed and we specifically find their immediate respond to any site queries commendable. Due to the rigour, quantified evaluation and engineering solution, it had a huge impact on the success of the project.
I fully endorse TJ Engineers for their broad skill of engineering services, including ESD analysis through to highly effective and tactical engineering strategies. Michel Loo - Design Partner at Innermode
How to Identify and Control Harmonics In Your Commercial Building
Written by Kay Chew (Senior Electrical engineer) – May 2021
Image Source: Unsplash
Every commercial building relies on the supply of power and the efficiency of technology. Failure to maintain these foundational aspects of your commercial building and you can quickly face a logistical and financial nightmare.
As equipment and technology can fail in the presence of harmonic voltage, it’s crucial you know how to identify, assess and control harmonics in your commercial building.
TJ Consulting is proud to provide reliable, efficient, economical and sustainable design solutions to support the needs of your commercial systems and technologies.
Read on to discover why harmonics pose a risk to your commercial building, and how to effectively identify and control harmonic effects.
What are harmonics?
Harmonics are currents or voltages are a distortion of the normal electrical current waveform, with frequencies that are integer multipliers of the fundamental power frequency.
As an example, if the fundamental power frequency is 50 Hz, the second harmonic is 100 Hz, the third harmonic is 150 Hz and so on. Harmonics are created by non-linear loads drawing current in pulses, as opposed to a streamlined sinusoidal manner.
Pulses contribute to distorted wave shapes which cause harmonic currents to flow back into your power system – which can lead to significant negative outcomes for commercial buildings.
How are harmonics generated?
Any electronic load is capable of generating harmonics. However, harmonic currents and voltages are typically generated by non-linear loads. Non-linear loads exist in the form of personal computers, multi-function devices (MFDs), battery chargers, UPSs, motor starters, variable speed drives (VSDs), electronic control gears and switch mode power supplies (SMPS).
If these technologies create the image of a bustling commercial workspace, you’re picturing the exact environment susceptible to harmonics. As these non-linear power supplies draw current in high-amplitude short pulses, they create distortion in the electrical current which moves back into the power source and places all equipment connected to that same source at risk.
What harmonic risks exist to my commercial building?
The presence of harmonics may distort the voltage and current waveform in your electrical distribution network. This may affect other users connected to the same network. As a result, the disturbance can cause network overloading, leading to:
- Utility bills tariff and operational cost penalties
- Equipment malfunction
- Increased internal energy losses and lower equipment lifespan
- Metering errors
- Generator failures
How can I measure and resolve harmonics?
The harmonics generated in commercial buildings can be evaluated and measured through power system audits and harmonic filters.
This helps to ensure appropriate steps are taken to reduce harmonics effects and to avoid potential equipment failure and tariff penalties.
In many cases, electrical installation regulations impose a maximum 5% limit for the Total Harmonic Distortion (THD) at the point of common coupling. However, it is the responsibility of the end-user to ensure the harmonics generated are filtered to a safe level. This level is required to eliminate disturbances to other loads connected to the same network.
Where there is a significant presence of multiple sources of high level harmonic distortions (i.e. commercial buildings with high amounts of servers, VSDs etc.), it may be viable for building operators to engage power system specialists to audit the existing power quality. Where needed, consider installing power system optimisers or harmonic filters to achieve higher power quality. Ultimately, these filtering measures increase the performance and efficiency of your electrical system.
What are the benefits of harmonic filters?
Active harmonic filters enable users to meet power quality demand, and gain flexibility and control of the filters – as they are instantaneous sine wave conditioners.
The filter can be connected in parallel at the electrical switchboard to provide conditioning and filtering compensation. This measures the harmonic currents generated from the non-linear loads, and injects the same amount of harmonic current in an opposite phase to cancel harmonics and ensure the line current remains sinusoidal.
The importance of auditing to identify the correct filter specification
It is essential to audit and measure the existing building power quality in order to select a right filter specification.
This will ensure a flexibility of filtering to cater for load fluctuations and the extent of total harmonic voltage distortion at the point of common coupling.
In addition, the range of frequencies to be filtered, as well as the harmonics order to be filtered, can be programmed via a microprocessor based filter controller. This will enable filtration level presets for each selected harmonic order to a level within the required tolerance.
The result is a more efficient use of the available compensation power and achieving higher power quality.
Are you looking for an energy assessment or support within your commercial building? Contact TJ Consulting for a complimentary consultation today.