You can directly connect Simscape Specialized Power System blocks with Simulink blocks, without the need of any convertors. Here is a minimal example demonstrating the same:
For more examples using Specialized Power System blocks, refer to the following page: https://mathworks.com/help/sps/examples.html?category=specialized-power-systems
For other Simscape Physical System blocks, you can use 'PS-Simulink Convertor' to convert physical signals to simulink signals. For more information, refer to the following documentation: https://mathworks.com/help/simscape/ref/pssimulinkconverter.html
Hope it helps!
