ISRO Scientist Electrical study plan

Solve 40 network-theorems problems (Thevenin, Norton, superposition, reciprocity) and verify at least 10 of them by re-solving with mesh or nodal analysis to confirm the answers agree.

Derive and apply the transient response of first-order RL and RC circuits for step and DC-source switching, writing the time constant and initial/final conditions from memory for 15 circuits.

Compute two-port parameters (z, y, h, ABCD) for 10 given networks and convert between parameter sets without looking up the conversion table.

Draw the phasor diagram and compute voltage regulation for a single-phase transformer at 0.8 lagging, unity and 0.8 leading power factor, using the equivalent circuit you construct yourself.

Sketch the no-load and load characteristics of a separately excited DC generator and explain in writing why the shunt generator fails to build up voltage in three fault cases.

Derive the torque-speed expression of a three-phase induction motor from the equivalent circuit and compute starting torque, maximum torque and slip at maximum torque for 8 machines with given parameters.

Solve 15 DC machine problems involving armature reaction, commutation, back EMF and speed control by armature voltage and field flux, stating units at every step.

Analyze three-phase balanced and unbalanced loads using symmetrical components, computing sequence networks for 6 fault cases (LG, LL, LLG, LLL).

Construct the power-angle characteristic of a cylindrical-rotor synchronous generator and determine steady-state stability limit and load angle for 5 operating points.

Compare transformer and induction machine losses by computing efficiency at full load, half load and maximum-efficiency load for 6 machines.

Build the per-unit model of a 3-bus power system and solve load flow by Gauss-Seidel for 2 iterations, then compare against Newton-Raphson for the same system.

Compute line parameters (inductance, capacitance) for single-circuit and double-circuit three-phase lines with given conductor spacing and bundling, for 6 configurations.

Select and coordinate overcurrent relays for a radial feeder with 4 buses: set pickup and time-multiplier values and verify grading margins.

Analyze a three-phase fully controlled bridge rectifier with R-L load: derive average output voltage versus firing angle and compute THD of input current for 4 firing angles.

Compare buck, boost and buck-boost converters by deriving voltage conversion ratio in continuous conduction mode and identifying the boundary conduction condition for each.

Derive transfer functions for 10 electromechanical systems (DC motor with load, RLC networks, thermal and fluid analogues) using Laplace transforms.

Apply Routh-Hurwitz, root locus and Bode/Nyquist criteria to determine stability margins for 12 given loop transfer functions, stating gain margin and phase margin numerically.

Design a lag, lead and lag-lead compensator for 3 given specifications using Bode plots and verify the design by hand-computed closed-loop step response.

Model a DC-DC converter-driven DC motor and compute steady-state speed and armature current under armature-voltage control for 5 duty-cycle values.

Explain in writing how PWM switching frequency and dead time affect current ripple and low-speed torque in an inverter-fed induction motor drive.

Analyze 15 op-amp circuits (inverting, non-inverting, instrumentation, active filters, Schmitt trigger) computing gain, bandwidth and output offset error.

Design combinational and sequential logic for 8 specifications using K-maps, multiplexers and flip-flops, then verify each design with a hand-drawn timing diagram.

Compute Fourier series and Fourier transforms for 10 standard signals and state the sampling theorem implications for a given anti-aliasing filter.

Solve 12 z-transform problems including region of convergence and stability of discrete systems, and relate pole locations to time-domain response.

Specify instruments for measuring voltage, current and power in a high-voltage AC circuit: choose CT/PT ratios, compute burden and explain error sources in electrodynamometer and digital meters.

Solve 12 symmetrical and unsymmetrical fault problems using sequence networks, computing fault current and post-fault voltages at each bus.

Select switchgear ratings for a given fault level: compute short-circuit MVA, choose breaker breaking capacity and check making capacity and thermal withstand.

Compute electric field and potential for 8 electrostatic configurations (coaxial cable, parallel plates, sphere gaps) using Gauss's law and Laplace's equation.

Explain and compute corona inception voltage, surge impedance of overhead lines and reflection/refraction coefficients at a line termination for 5 cases.

Describe the standard lightning impulse and switching impulse waveforms and compute the 50% flashover voltage estimate from a simplified up-and-down test record.

Solve 20 engineering-mathematics problems covering eigenvalues and diagonalization, partial derivatives and maxima, and first- and second-order ODEs with initial conditions.

Apply numerical methods by hand: 3 iterations each of Newton-Raphson, bisection, trapezoidal/Simpson integration and Euler/RK-4 for one ODE, reporting error estimates.

Solve 25 aptitude items under a 30-minute timer (quantitative, logical, verbal) and classify every error by cause.

Write and dry-run 10 C programs covering pointers, arrays, structures and recursion, predicting the output before compiling.

Trace 10 data-structure operations (stack, queue, linked list, binary search tree) and state time complexity for each operation.

Take three full-length timed mock tests under exam conditions and score each by domain to identify the two weakest domains.

Re-solve every problem in the error notebook from weeks 1 to 7 without notes and mark any that still fail.

Re-derive the 30 most-used formulas (transformer regulation, torque-slip, per-unit, compensator gains, converter ratios, sequence networks) from first principles in one sitting.

Review the two weakest domains with 20 targeted problems each until accuracy exceeds 80 percent.

Consolidate a final two-page quick-reference sheet limited to formulas you have personally derived and verified.