Measuring Transfer Functions of Continuous-Time Systems

 Introduction:

Have you ever wondered how to measure transfer functions of continuous-time systems? Join us as we delve into the fascinating world of transfer function measurement using simscape implementation of a t-coil circuit. Whether you're a seasoned engineer or just starting out, this blog will unravel the complexities and provide practical insights into this essential process.

Setting Up the Measurement Parameters

To begin the journey of measuring transfer functions, it's crucial to define the inputs and outputs using voltage sensors and controlled voltage sources. These parameters act as the foundation for accurate measurements and provide the groundwork for the subsequent steps.

Transitioning to Frequency Domain Measurement

Once the basic setup is complete, the transition from time domain measurement to frequency domain measurement is critical. Setting the hold off time to zero and running the measurement for a longer duration enables obtaining a comprehensive transfer function for the system.

Exploring the Mask Subsystem

The mask subsystem plays a pivotal role in the measurement process, allowing for in-depth examination of the excitation and measurement portions within the system. Understanding its workings is essential for accurate and reliable measurements.

Analyzing Band Limiting and Sampling Aspects

Analyzing the band-limiting and sampling aspects is crucial for ensuring accurate measurements. By delving into these technical aspects, we can minimize errors and obtain precise transfer function data.

Utilizing Transfer Function Estimator Blocks

The implementation of transfer function estimator blocks as system objects facilitates the computation of cross spectrum and auto spectrum, enabling a deeper understanding of the complex response output. Whether creating custom libraries or utilizing pre-built blocks, these tools streamline the measurement process for efficiency.

Measuring Transfer Functions for Highpass Systems

In the realm of highpass systems, overcoming challenges such as aliasing effects and inadequate attenuation of high frequencies is essential. Employing a larger number of averages can effectively minimize the aliasing effect, ensuring accurate measurements and minimizing distortion.

Conclusion:

Measuring transfer functions of continuous-time systems is a nuanced process that demands attention to detail and a deep understanding of the underlying principles. By mastering the techniques explored in this blog, you can unlock the secrets of transfer function measurement and gain valuable insights into system behavior.

Watch this video to demonstration 

Learn how to quickly measure transfer functions of continuous-time systems in Simulink®. This measurement is an extension or generalization of the transfer function measurement approach for discrete-time systems.

Measurements on continuous-time systems have the additional challenge that proper sampling and alias filtering is required whereas for a discrete-time systems, those aspects are either less important or not relevant at all. The device under test (DUT) is a T-coil circuit built out of passive Simscape™ components. The starting point is an already designed T-coil circuit. But you still need to verify the circuit implementation. In other words, does your T-coil circuit have the expected magnitude and phase response? In this case, the circuit’s theoretical frequency response has been pre-derived using Symbolic Math Toolbox™.