Technical FAQs 4

What is the role of a DC link capacitor in inverter systems?

Before diving into the calculations, it is important to understand the role of a DC link capacitor in inverter systems. The primary function of a DC link capacitor is to smooth out the DC bus voltage between the rectifier and inverter stages, which helps in reducing voltage ripple and preventing voltage spikes.

What is a DC-link capacitor in a traction inverter?

Figure 1. Simplified Block Diagram of a Traction Inverter The DC-Link capacitor is a part of every traction inverter and is positioned in parallel with the high-voltage battery and the power stage (see Figure 1). The DC-Link capacitor has several functions, such as to help smooth voltage ripples, filtering unwanted harmonics and reducing noise.

What is a DC link capacitor?

Inverter design plays a pivotal role in many modern power electronics applications, from renewable energy systems to motor drives. One of the critical components in an inverter circuit is the DC link capacitor. This capacitor helps stabilize the DC voltage and minimize voltage ripple, ensuring efficient and reliable operation of the inverter.

Why do inverters need a capacitor?

The capacitor helps maintain the desired voltage level by reducing the ripple generated by the inverter's switching operations. The inverter’s power rating determines how much current is drawn from the DC bus. Higher power ratings require larger capacitors to ensure adequate energy storage and voltage stabilization.

Photovoltaic Storage & BESS Technical Resources


Expert insights on photovoltaic energy storage systems, BESS solutions, mobile power containers, EMS management systems, commercial storage, industrial storage, containerized storage, and outdoor power generation for South African and African markets

Inverter plus DC capacitor

Welcome to our technical resource page for Inverter plus DC capacitor! Here, we provide comprehensive information about photovoltaic energy storage systems, BESS solutions, mobile power containers, EMS management systems, commercial storage, industrial storage, containerized storage, and outdoor power generation. Our professional engineering solutions are designed for residential, commercial, industrial, and utility applications across South Africa and Africa.

We provide professional photovoltaic storage and BESS solutions to customers across South Africa, including Western Cape, Gauteng, KwaZulu-Natal, Eastern Cape, Free State, and neighboring African countries including Namibia, Botswana, Zimbabwe, Mozambique, Zambia, Tanzania, and Kenya.
Our expertise in photovoltaic energy storage systems, BESS solutions, mobile power containers, EMS management systems, commercial storage, industrial storage, and containerized storage ensures reliable performance for various applications. Whether you need residential photovoltaic storage, commercial BESS systems, industrial energy storage, mobile power containers, or utility-scale photovoltaic projects, WALMER ENERGY has the engineering expertise to deliver optimal results with competitive pricing and reliable technical support.

CAPACITORS

Oct 20, 2021 · The AC output filter is a low pass filter (LPF) that blocks high frequency PWM currents generated by the inverter. Three phase inductors and capacitors form the low pass

High-Performance DC Link Capacitors

Dec 2, 2025 · Our high-performance DC link capacitors enable fast switching in inverters, offering optimized bus topologies, high current ratings & low

DC Link Capacitors Selection and Arrangement Procedure in

Dec 28, 2023 · The most important parasitic elements in high-power inverters are the ones associated with the DC-link and the capacitors used in its structure. This article will describe

Selecting dc-link capacitors for inverters

Feb 9, 2021 · One key factor: Determining the nuances of how capacitors handle expected ripple currents. Sam G. Parler, Jr., P.E. Cornell Dubilier

Selecting dc-link capacitors for inverters

Feb 9, 2021 · One key factor: Determining the nuances of how capacitors handle expected ripple currents. Sam G. Parler, Jr., P.E. Cornell Dubilier Examine a dc link capacitor''s ac ripple

High-Performance DC Link Capacitors

Dec 2, 2025 · Our high-performance DC link capacitors enable fast switching in inverters, offering optimized bus topologies, high current ratings & low inductance.

Selecting and Applying DC Link Bus Capacitors for

May 16, 2023 · Sam G. Parler, Jr., P.E. Cornell Dubilier Abstract, aluminum electrolytic and DC film capacitors are widely used in all types of inverter power systems, from variable-speed

Importance of DC-Link Capacitors in High Power Inverter

Mar 11, 2025 · This article explores the importance of DC-link capacitors, their functional role in high-power inverters, and key parameters to consider when selecting them.

Selecting Capacitors for Inverter Applications

This paper will present a practical mathematical approach on how to properly size a bus link capacitor for a high performance hard switched DC to AC inverter using film capacitors and will

How to configure capacitors for inverters

You need to sync the phases. Some inverters, such as many MPP units, can be paralleled, so that the AC outputs can be combined. With most off-grid inverters, this is not the case. There

How to Reduce the Power Resistor for DC-Link

Aug 16, 2024 · The DC-Link capacitor is a part of every traction inverter and is positioned in parallel with the high-voltage battery and the power stage (see Figure 1). The DC-Link

Importance of DC-Link Capacitors in High

Mar 11, 2025 · This article explores the importance of DC-link capacitors, their functional role in high-power inverters, and key parameters to

DC Link Capacitor Calculation for Inverter

Oct 5, 2024 · Learn how to calculate the DC link capacitor for inverters, taking into account power rating, voltage ripple, switching frequency, and load dynamics. Ensure your inverter operates

WALMER ENERGY Engineering Support Team

Engineering Support for Photovoltaic Storage & BESS Projects

Our certified engineering team provides comprehensive technical support for all installed photovoltaic storage and BESS systems. From initial system design and engineering to ongoing maintenance, optimization, and performance monitoring, WALMER ENERGY ensures your photovoltaic storage and BESS solutions operate at peak efficiency throughout their lifecycle, with 24/7 monitoring available for critical industrial and commercial applications.

Contact Engineering Support

Stay Updated on Photovoltaic Storage & BESS Technology

Subscribe to our technical newsletter for the latest innovations in photovoltaic energy storage systems, BESS solutions, mobile power containers, lithium batteries, EMS management systems, and industry developments across Africa. Stay informed about cutting-edge solutions in renewable energy technology.