What Should Be Considered in Compensation Solutions?

In electrical infrastructures, compensation is often seen as a solution to “avoid reactive energy penalties.

In electrical infrastructures, compensation is often seen as a solution to “avoid reactive energy penalties.” However, a properly designed compensation solution improves active power management, creating a more compatible structure with the grid, ensuring more stable operation of equipment, and enabling continuous maintenance.

At Aha Technology, we approach compensation not as a standalone piece of equipment, but as an engineering issue that directly impacts the continuity of the facility and the stability of the infrastructure.

In this article, we summarize the critical points to consider in compensation solutions and the correct project approach.

What is Compensation, Why is it Done?

Compensation is applied to control the reactive power generated in facilities and to bring the power factor (cosφ) closer to the target level. Reactive power increases in facilities with a high concentration of motorized loads, drives (VFD), transformers, and inductive equipment.

The main objectives of compensation are:

·         To control reactive energy consumption

·         To help reduce the current drawn from the grid

·         To reduce unnecessary load on transformers and cables

·         To support system stability and operational continuity

However, selecting a capacitor bank alone is not sufficient to achieve the expected benefits of compensation. The right result is achieved through proper analysis and proper design.

1) First Step: Analyze the Facility's Load Profile and Grid Conditions

Each facility has a different load profile and operating characteristics. Therefore, it is critical to take measurements and analyze load behavior before determining the compensation solution.

Key parameters to be evaluated:

·         Rate of change of loads during the day (sudden load increases and decreases)

·         Periodic change in inductive–capacitive behavior

·         Harmonic levels and harmonic sources (drives, UPS, rectifier loads, etc.)

·         Transformer power, short-circuit power, and main distribution structure

·         Point where compensation will be applied (main distribution panel, sub-panels, local compensation)

Systems selected without this analysis often result in insufficient step response, unstable operation, shortened capacitor life, and unnecessary investment costs.

2) The Right Type of Compensation Must Be Selected: Classic or New Generation?

One of the most important decision points in compensation systems is the rate of change in the facility's reactive power demand and the operating characteristics of the loads. In facilities where reactive power demand changes slowly, classic stepped compensation systems may be a suitable solution. However, in applications where the load changes rapidly, the cosφ value fluctuates frequently, or large loads are instantly switched on in the process, standard compensation systems may sometimes operate erratically.

This instability should not be considered merely as momentary performance fluctuations. Incorrect type selection or configurations unsuitable for the site can result in more frequent switching on and off of stages, faster wear of components, and increased monitoring/maintenance requirements for the system. Therefore, when selecting a compensation solution, it is important to evaluate not only the initial investment cost but also the total cost of ownership over 10 years (including maintenance, parts replacement, labor, and downtime risks).

New generation compensation approaches should be evaluated in such facilities. In Aha Technology projects, solutions that can provide dynamic reactive power control, such as Static Var Generator (SVG), can be implemented depending on the needs in the field. These solutions are preferred for their faster response and more stable control in variable load conditions.

3) Compensation Should Not Be Considered “On Its Own” If Harmonics Are Present

One of the most critical issues affecting the performance of compensation systems is harmonics. In facilities with high harmonic content, various risks may arise if the compensation system is not designed appropriately.

The main problems that can be seen in infrastructures with harmonics are:

·         Excessive current and heating in capacitors

·         Instability in step control

·         Resonance risks

·         Protection elements coming into operation and system interruptions

Therefore, in compensation projects, power quality parameters must be measured and harmonic effects must be evaluated. Depending on the need, the compensation solution should be considered together with Active Harmonic Filter (AHF) solutions aimed at reducing harmonic effects.

4) The Stage Structure and Control Strategy Must Be Correctly Designed

The stable operation of the compensation system in the field depends on the correct selection of the stage structure and the correct design of the control strategy. Incorrect stage ratios can result in unnecessary switching, difficulty in approaching the target cosφ value, and unstable system operation.

Key points to consider:

·         Selecting the number of stages and stage ratios appropriate for the load profile

·         Accuracy of measurement and control algorithm capability of the control equipment used

·         Correct selection of current transformers (CT) and measurement connections

·         Correct determination of the measurement point

The limitations of the tap-changing approach become more apparent, especially with rapidly changing loads. In such cases, dynamic solutions (e.g., SVG) may be a more suitable option.

5) An Engineering Approach Tailored to Needs Should Be Preferred Over a “Standard Panel”

In compensation applications, the correct result is achieved not only through product selection but also through the proper execution of all steps, including measurement, design, commissioning, and verification. Therefore, an “engineering-focused” approach should be preferred over a “supply-focused” approach.

Aha Technology's approach:

·         Analyze the facility's needs and existing problems based on measurements

·         Configure the solution according to field conditions

·         Verify performance in the field during commissioning processes

·         Build a structure that supports long-term operational continuity

6) Commissioning, Measurement, and Periodic Inspection Processes Must Not Be Neglected

Compensation systems must be reevaluated over time according to the changing needs of the facility. The addition of new loads, changes in production capacity, or an increase in harmonic sources such as drives/UPS directly affect compensation performance.

Therefore:

·         Target values should be verified by measurement during commissioning

·         System operating data should be monitored and reported

·         A periodic maintenance and inspection plan should be implemented

·         Capacitors and switching elements should be inspected regularly

This discipline helps maintain the system's stable and sustainable operation.

Conclusion: Proper Compensation is Part of Power Quality Management

The right result in compensation solutions is achieved through system selection appropriate to the load profile, evaluation of harmonic effects, the correct stage structure, and proper commissioning processes. Applications based solely on a standard panel approach may appear to work in the short term, but can create instability and failure risks in the long term.

At Aha Technology, we approach compensation solutions within an energy quality framework. We aim to determine the most suitable structure by utilizing next-generation compensation systems such as SVG (Static Var Generator) and AHF (Active Harmonic Filter) solutions according to specific needs.

We can evaluate your load profile and power quality parameters together to determine the most suitable compensation approach for your facility.