Ensuring stability of a remote power station in Australia

Segment background

In Northern Australia, a remote off-grid power station encountered issues with power quality due to the high number of VFD-controlled loads present in its network. VFDs, or Variable Frequency Drives, are devices that can adjust the speed of motors that power equipment such as pumps and fans. However, the use of VFD-controlled loads can result in a variety of power quality issues, including high harmonic current distortion and other disturbances that can impact the power supply’s reliability and efficiency.

One of Australia’s largest energy producers has a remote off-grid power station that includes multiple systems, such as gas-fired micro-turbines, battery storage, solar, and wind power systems. Gas-fired micro-turbines are small gas turbines that can generate electricity and heat, often used in distributed generation systems.

Challenges at the customer’s off-grid network

The power plant feeds a network with a high number of VFD-controlled loads, which is the main cause of the poor power quality in this system. VFDs amplify the harmonics in the network because the output they generate is not fully sinusoidal. The most problematic harmonic components in this type of network are usually 5th, 7th, 11th, and 13th.

Harmonic currents shorten the lifetime of components in the network and may even cause the failure of critical machinery. The customer was also facing unnecessarily high losses in the pump motors and distribution lines, which can decrease the capacity of the network and result in a more expensive electricity bill.

Our Merus^® Solution

Ampcontrol, our local partner, installed three Merus^® A2 – 200A Active Harmonic Filter modules on the site, so the total compensation capacity is 600A. Module cabinets were designed so that there will be room to expand the compensation capacity up to 800 A in the future if needed.

Results after installation

After successfully installing and commissioning the Merus^® A2 – Active Harmonic Filters, the harmonics caused by VFD-controlled loads were successfully mitigated, operation of the micro-turbine, solar, and wind power systems was secured, and the overall reliability of the power station was ensured.

The fast response time of the Merus^® A2 – Active Harmonic Filters was critical in mitigating the harmonics caused by the fast-fluctuating loads in the network. This helps to prevent damage to the equipment and maintain the efficiency of the whole network. Merus^® A2 – Active Harmonic Filters enable a continuous operation of the complex power generation system, reduce energy losses, lower maintenance costs, and enable longer lifespan of critical equipment. Since the solution has room for expanding the compensation capacity, the customer doesn’t have to worry if loads and production capacity in the network need to be increased.