I wish I had a more general answer, but I can give a specific example.
In order to work with circuits, differential equations (an area of calculus) must be used to understand and study the relationships between current, voltage, resistance, power, and work.
in which field vector calculus is applied deeply
For Literally Everything.
Engineering careers, physicists, mathematicians, economists.
It is used to position an object in3D
The difference between Leibniz calculus to Newton calculus was that Leibniz developed Newton's calculus into the calculus we all know today. For instance, diffentiation and intergration, limits, continuity, etc. This type of calculus was the pure mathematics. On the otherhand, the calculus which Newton found was that used in physics, such as speed and velocity which helped with physics greatly. Today, calculus not only used in just mathematics or physics, but used in finance, as well as exploited in engineering.
Vector calculus is applied in electrical engineering especially with the use of electromagnetics. It is also applied in fluid dynamics, as well as statics.
"Electrical Engineering"
To find expert advice and solutions related to electrical engineering on the Electrical Engineering Stack Exchange platform, you can create an account on the website and then search for relevant topics or questions. You can also ask your own questions and engage with the community of electrical engineering professionals to get the help you need.
The majors that require calculus are all mathematics, science, and engineering majors. These include (but are not limited to) mathematics, mathematics education, science education, biology, chemistry, physics, civil engineering, chemical engineering, biological engineering, electrical engineering, biochemistry, pharmeceuticals, and computer science. So about 99% of students in those majors and related majors will take calculus their freshman year (typically the second semester). I say 99% because calculus is a prerequisite for all other courses in those majors (so it must be taken very early), but there is a very small possibility (I'd say 1% chance) that students can take calculus their sophomore year instead.
regarding substation
Most complex engineering problems cannot be solved without calculus. Force related problems are a great example - how else would you calculate the force exerted on a particle a specific distance from an electrically charged wire?
in which field vector calculus is applied deeply
honors physics / ap physics honors pre-calculus / ap calculus AB/BC honors chemistry engineering mechanics
automatic missile guidence systemi want some mini projects on electrical engineering
CALCULUS
For Literally Everything.
These are the general math courses in an undergraduate program of Mechanical Engineering. Actually, these are also the math courses required in ANY undergraduate Engineering curriculum: Algebra Trigonometry Analytic Geometry Differential Calculus Integral Calculus Mutivariable Calculus Differential Equations