Waldenburg (Germany) – Würth Elektronik expands its free design tool REDEXPERT to include the Current Sense Transformer Selector. It enables developers to select the appropriate current sense transformers based on parameters relevant to their application.
Current sense transformers for measuring alternating current offer unique advantages over other current sensing solutions: galvanic isolation, low power loss, high immunity to signal noise, and simple circuit design. Selecting the right current sensor can be a challenge depending on the application. The Current Sense Transformer Selector from Würth Elektronik offers a unique design tool previously not available on the market in this form.
Source: Würth Elektronik
Including simulation
After entering the parameters – current, frequency, signal type, and desired maximum error rate – the Selector finds all available options in Würth Elektronik’s product database that match these criteria. The tool provides a list of components with the corresponding parameters and simulates both the temperature rise and the error as a function of frequency and current. The tool also allows the direct comparison of different options in a simulation view and provides an overview page with all relevant information for the selected component. These simulations, based on actual measurements, save developers from having to conduct their own tests when selecting current sense transformers (CSTs).
Source: Würth Elektronik
The selection process without the REDEXPERT Current Sense Transformer Selector is as follows: First, the CST must be selected with a suitable ET constant to ensure it doesn’t reach saturation even under unfavorable conditions – i.e. low frequencies and high currents. It’s also important to ensure that the CST doesn’t overheat at maximum current. Last but not least, the error characteristics required for the specific application must also be taken into account when selecting the component. As datasheets for CSTs don’t cover all possible application-relevant parameters – and can’t realistically do so in practice – it’s often necessary to test several components to make the best choice.
Applications
Typical applications of current sense transformers include AC current measurement, switched-mode power supplies, overload detection, load shedding/shutdown detection, metering, load measurement, and high-frequency current sensing.
