Optional
Electrical Engineering
UPSC Civil Services Mains, optional subject
Syllabus
Paper I
- Circuits—Theory
- Circuit components
- network graphs
- KCL, KVL
- Circuit analysis methods : nodal analysis, mesh analysis
- basic network theorems and applications
- transient analysis : RL, RC and RLC circuits
- sinusoidal steady state analysis
- resonant circuits
- coupled circuits
- balanced 3-phase circuits.
- Two-port networks.
- Signals and Systems
- Representation of continuous-time and discrete-time signals and systems
- LTI systems
- convolution
- impulse response
- time-domain analysis of LTI systems based on convolution and differential/difference equations.
- Fourier transform, Laplace transform, Z-transform, Transfer function.
- Sampling and recovery of signals DFT, FFT Processing of analog signals through discrete-time systems.
- E.M. Theory
- Maxwell’s equations, wave propagation in bounded media.
- Boundary conditions, reflection and refraction of plane waves.
- Transmission lines : travelling and standing waves, impedance matching, Smith chart.
- Analog Electronics
- Characteristics and equivalent circuits (large and small-signal) of Diode, BJT, JFET and MOSFET. Diode circuits : Clipping, clamping, rectifier.
- Biasing and bias stability.
- FET amplifiers.
- Current mirror
- Amplifiers : single and multi-stage, differential, operational feedback and power.
- Analysis of amplifiers
- frequency-response of amplifiers.
- OPAMP circuits.
- Filters
- sinusoidal oscillators : criterion for oscillation
- single-transistor and OPAMP configurations.
- Function generators and wave-shaping circuits.
- Linear and switching power supplies.
- Digital Electronics
- Boolean algebra
- minimisation of Boolean functions
- logic gates
- digital IC families (DTL, TTL, ECL, MOS, CMOS). Combinational circuits : arithmetic circuits, code converters, multiplexers and decoders.
- Sequential circuits: latches and flip-flops, counters and shift-registers.
- Comparators, timers, multivibrators.
- Sample and hold circuits, ADCs and DACs. Semiconductor memories.
- Logic implementation using programmable devices (ROM, PLA, FPGA).
- Energy Conversion
- Principles of electromechanical energy conversion : Torque and emf in rotating machines.
- DC machines : characteristics and performance analysis
- starting and speed control of motors.
- Transformers : principles of operation and analysis
- regulation, efficiency
- 3-phase transformers. 3-phase induction machines and synchronous machines : characteristics and performance analysis
- speed control.
- Power Electronics and Electric Drives
- Semi-conductor power devices : diode, transistor, thyristor, triac, GTO and MOSFET-static characteristics and principles of operation
- triggering circuits
- phase control rectifiers
- bridge converters : fully-controlled and half-controlled
- principles of thyristor choppers and inverters
- DC-DC converters
- Switch mode inverter
- basic concepts of speed control of dc and ac motor drives applications of variable-speed drives.
- Analog Communication
- Random variables : continuous, discrete
- probability, probability functions.
- Statistical averages
- probability models
- Random signals and noise : white noise, noise equivalent bandwidth
- signal transmission with noise
- signal to noise ratio.
- Linear CW modulation : Amplitude modulation : DSB, DSB-SC and SSB. Modulators and Demodulators
- Phase and Frequency modulation : PM & FM signals
- narrows band FM
- generation & detection of FM and PM, Deemphasis, Preemphasis.
- CW modulation system : Superhetrodyne receivers, AM receivers, communication receivers, FM receivers, phase locked loop, SSB receiver Signal to noise ratio calculation or AM and FM receivers.
Paper II
- Control Systems
- Elements of control systems
- block-diagram representations
- open-loop & closed-loop systems
- principles and applications of feed-back.
- Control system components.
- LTI systems : time-domain and transform-domain analysis.
- Stability : Routh Hurwitz criterion, root-loci, Bode-plots and polor plots, Nyquist’s criterion
- Design of lead-lad compensators.
- Proportional, PI, PID controllers.
- State-variable representation and analysis of control systems.
- Microprocessors and Microcomputers
- PC organisation
- CPU, instruction set, register set timing diagram, programming, interrupts, memory interfacing, I/O interfacing, programmable peripheral devices.
- Measurement and Instrumentation
- Error analysis
- measurement of current voltage, power, energy, power-factor, resistance, inductance, capacitance and frequency
- bridge measurements.
- Signal conditioning circuit
- Electronic measuring instruments : multimeter, CRO, digital voltmeter, frequency counter, Q-meter, spectrum-analyser, distortion-meter.
- Transducers : thermocouple, thermistor, LVDT, strain-guage, piezo-electric crystal.
- Power Systems: Analysis and Control
- Steady-state performance of overhead transmission lines and cables
- principles of active and reactive power transfer and distribution
- per-unit quantities
- bus admittance and impedance matrices
- load flow
- voltage control and power factor correction
- economic operation
- symmetrical components, analysis of symmetrical and unsymmetrical faults.
- Concepts of system stability : swing curves and equal area criterion.
- Static VAR system.
- Basic concepts of HVDC transmission.
- Power System Protection
- Principles of overcurrent, differential and distance protection.
- Concept of solid state relays.
- Circuit breakers.
- Computer aided protection : introduction
- line, bus, generator, transformer protection
- numeric relays and application of DSP to protection.
- Digital Communication
- Pulse code modulation (PCM), differential pulse code modulation (DPCM), delta modulation (DM), Digital modulation and demodulation schemes : amplitude, phase and frequency keying schemes (ASK, PSK, FSK). Error control coding : error detection and correction, linear block codes, convolution codes.
- Information measure and source coding.
- Data networks, 7-layer architecture.
Syllabus as published by UPSC in the Civil Services Examination 2026 notification.