In short. Automation decides how a power system behaves when nobody is watching: which generators start, how they synchronise and share load, when load is shed or restored, how transfers happen, and what operators see on the screen. Good control design is layered, fail-safe and testable. These guides cover the control hierarchy, PLC and power management systems, generator sequencing, transfer and interlocking logic, BESS and hybrid dispatch, SCADA and alarms, and how the whole system is accepted before handover.
Where to start
| If your question is… | Start with |
|---|---|
| Choosing a control architecture for a requirement | Electrical Control Requirement → Automation Architecture Selection Guide |
| Running several generators automatically | Multi-DG Automatic Sequencing and Dispatch Control |
| Automatic synchronising | Automatic Synchronising Control Architecture |
| Mains-fail transfer logic | ATS / AMF Control Logic Engineering |
| Shedding and restoring load automatically | Load-Shedding Automation and Priority Logic |
| Monitoring and SCADA | SCADA Architecture for Power Systems |
| Testing control logic before handover | Power-Control FAT / SAT / Functional Acceptance Framework |
All 42 guides in this section
- Power Control, Automation and Intelligence Architecture — How power control is layered from relays and interlocks to PLCs, power management, SCADA and analytics, and how each layer should behave when the one above it fails.
- Electrical Control-System Architecture and Control Hierarchy — How to organise electrical control into levels from field devices to plant controllers and supervision, define who has authority at each level, and avoid conflicts between controllers.
- Local, Remote, Automatic and Supervisory Control Philosophy — How to define control modes for generators, breakers and transfer systems: who may operate, mode priority, handover rules, lockouts and the safeguards that keep manual work safe.
- PLC Architecture for Electrical Power Systems — How to design PLC control for power systems: scan time, I/O strategy, hard-wired safety, communications, program structure, cybersecurity and testing for generators, transfer and load management.
- Redundant PLC and High-Availability Control Architecture — How to design redundant control for critical power: hot standby, dual networks and I/O, bumpless switchover, power supplies, common-cause failures and tests that prove changeover.
- Power Management System (PMS) Architecture Guide — What a power management system does: generator dispatch, load sharing, load shedding, restoration and reporting, and how it sits among protection, device controllers and SCADA.
- Microgrid Controller Architecture — How a microgrid controller coordinates generators, solar, batteries and loads: grid-connected and island modes, hierarchy, frequency and voltage control, transitions and fall-back behaviour.
- Generator Plant Master Control Architecture — How a generator plant master controller coordinates sets, breakers, fuel, cooling and auxiliaries, with clear authority, alarms, modes and fall-back when the master or its network fails.
- Multi-DG Automatic Sequencing and Dispatch Control — How multiple generators start, stop and load automatically: load-dependent thresholds, priority rotation, reserve rules, failure replacement and the timing that keeps the bus stable.
- Generator kW Load-Sharing Control — How parallel generators share real power: speed droop, isochronous sharing lines, digital sharing, ramps, common problems like hunting and reverse power, and how to test sharing.
- Generator kVAr and Power-Factor Sharing Control — How parallel generators share reactive power: voltage droop, cross-current compensation, power-factor control with the utility, circulating current causes and how to test and tune AVRs.
- Automatic Synchronising Control Architecture — How automatic synchronisers work: speed and voltage matching, phase-angle closing with breaker time compensation, check-sync backup, timeouts and the failure cases that protect machines.
- Dead-Bus, Live-Bus and Sync-Check Control Logic — How to design breaker closing logic by bus state: dead-bus permissives and lockout, live-bus synchronising, sync-check windows, voltage sensing faults and preventing double closing.
- Utility-DG Transfer Control Architecture — How transfer between utility and generator is controlled: sensing, start and stability timers, transfer types, retransfer, motor residual voltage, neutral switching and the failure cases to test.
- ATS / AMF Control Logic Engineering — How ATS and AMF controller logic is built: inputs, source qualification, start and transfer states, test modes, alarms, fail-safe behaviour and checks that prove standby readiness.
- Main-Tie-Main Automatic Transfer Control — How main-tie-main schemes work: two incomers and a bus tie, transfer logic on loss of one source, interlocks, fault lockout, retransfer, fault-level limits and tests that prove no double feed.
- Closed-Transition and Momentary-Paralleling Control — How closed-transition transfer works: sync matching, momentary parallel time limits, utility approval, protection during the overlap, fault-level checks and failure responses.
- Load-Shedding Automation and Priority Logic — How automatic load shedding works: priority tiers, fast event-based and slow shedding, under-frequency backup, shed tables, restoration and tests that prove the plant survives a source loss.
- Automatic Load Restoration and Restart Control — How to restore loads after an outage or shed event: staged restart sequence, step sizes, delays, motor residual voltage, permissives, manual holds and verification that the source stays stable.
- Islanding Detection and Island-Transition Control — How a site detects loss of the grid and moves to island operation: detection methods, speed versus nuisance trips, planned and unplanned transitions, load matching and safe resynchronisation.
- Black-Start Automation and Restoration State Machine — How to automate restoration from total blackout: black-start source, dead-bus energisation, staged load pickup, inrush control, state machine design, manual fall-back and drills.
- UPS / STS / ATS Control Coordination — How UPS, static transfer switches and ATS interact: transfer timing, source acceptance windows, rectifier walk-in, battery recharge, bypass control and coordination tests for critical loads.
- Electrical Interlocking and Permissive Logic — How to design interlocks and permissives that prevent unsafe switching: mechanical, key and electrical interlocks, hard-wired versus software logic, bypass rules and testing of blocked paths.
- Control-Power and Fail-Safe Architecture — How to design control power: DC and UPS supplies, battery sizing, redundancy, monitoring, earth-fault detection and the fail-safe state of each device when power or signals are lost.
- Brownfield Power-Control Modernisation and Integration — How to modernise control on an existing power plant without an outage: survey, interface strategy, phased cut-over, parallel run, temporary supply, rollback and verification of old and new logic.
- Power-Control FAT / SAT / Functional Acceptance Framework — How to prove a power-control system works: test plan, FAT with simulation, SAT with live equipment, failure injection, performance measurements, punch lists, documentation and sign-off criteria.
- Electrical Control Requirement → Automation Architecture Selection Guide — Match what you need the power system to do to the right automation architecture, from a single AMF controller to PLC, PMS, EMS and SCADA, with the questions, data and risks at each level.
- Energy Management System (EMS) Architecture Guide — How an energy management system optimises generators, utility, solar and batteries for cost, fuel and emissions, and how it should be separated from real-time power control and protection.
- BESS Charge / Discharge Control Architecture — How battery storage is controlled: state of charge limits, ramp, charge and discharge modes, backup reserve, peak shaving, protection and coordination with generators and PCS.
- DG + BESS Hybrid Dispatch Control — How generators and batteries are dispatched together: loading targets, battery covering steps and peaks, reserve, recharge rules, mode transitions and limits that keep the plant stable.
- Grid-Forming / Grid-Following Mode Coordination — How grid-forming and grid-following sources work together: who sets voltage and frequency, droop and virtual inertia, mode changes, island stability and common control conflicts.
- Control State Machines and Sequence Engineering — How to design power-control sequences as state machines: states, transitions, guards, timeouts, safe fall-backs, recovery after restart and test methods that cover every path.
- Electrical Control Cause-and-Effect Engineering — How to build and use a cause-and-effect matrix for power control: causes, effects, voting, delays, trip versus alarm, review with operators and use as the master test document.
- SCADA Architecture for Power Systems — How SCADA for power systems is structured: field devices, gateways, servers, historian, HMI, data points, update rates, redundancy, time stamps, security and what must work if SCADA fails.
- HMI and Electrical Mimic Design Engineering — How to design operator screens for power systems: one-line mimics, colour and state conventions, navigation, command safeguards, alarm integration and screens that help during an outage.
- Electrical Alarm Rationalisation and Operator Decision Support — How to cut alarm floods in power systems: classification, priorities, first-out, suppression, shelving, response actions, flood analysis and measures that show whether alarms help operators.
- Sequence-of-Events and Disturbance Intelligence — How to capture and read sequence-of-events and disturbance records: time stamps, event lists, waveform records, trigger setup, first-cause analysis and turning records into reliability actions.
- IEC 61850 Substation Automation Architecture — How IEC 61850 structures substation automation: logical nodes, MMS, GOOSE, sampled values, network topologies, engineering workflow and testing for generator and distribution systems.
- Modbus, IEC 61850, DNP3 and Industrial Power Communications — How to choose and engineer industrial power protocols: Modbus RTU and TCP, DNP3, IEC 61850, IEC 60870-5-104, OPC UA, SNMP, with point mapping, polling, data quality, security and troubleshooting.
- Time Synchronisation and Electrical Event Correlation — How to synchronise clocks across relays, controllers and SCADA: GPS, NTP, PTP, IRIG-B, accuracy needs, time-quality flags, failures and using synced data to correlate events.
- OT Network Architecture for Critical Power — How to design operational-technology networks for power systems: zones and conduits, segmentation, redundancy, remote access, patching, logging and resilience when IT or internet links fail.
- Control-System Redundancy, Failure and Degraded Modes — How to plan for control failure: failure modes of controllers, networks and power, defined degraded modes, manual fall-back, alarms for lost redundancy and tests that prove the plant stays safe.
Questions engineers ask
What is a power management system?
A PMS supervises several generators and sources: it starts and stops sets to match load, shares load, sheds non-essential loads when capacity is short, and restores them in order.
What should a control system do if its PLC fails?
Fail safe: generators and breakers should stay in a safe state, with local manual control available. This is designed in through control-power and fail-safe architecture.
Engineering content reviewed by Srinivas Reddy, Managing Partner, Reddy Generators. For advice on your own site, send us your requirement or call 098852 01608.