Dispatchers Training Simulator (DTS) - Reference Guide

Provides the capability to transfer the most current dynamic data values from the EMS database or the previous DTS database into a desired DTS database. The subsystem allows for different numbers of equipment in the two databases. For newly created equipment, the instructor must fill in the dynamic data.

Receives the events defined by the instructor on a simulated time basis and stores them in the Scenario Event File.

Lets the instructor input scheduled interchange for external areas to model transactions with the internal generation control area. Also allows input of scheduled interchange between any two external areas to simulate other transactions.

Provides error checking for the DTS source data and determines the linkage between DTS source data and the equipment defined for the power system network model.

Receives simulation time commands initiated by the instructor to represent generating plant operator actions, including:

• Changing generating unit local/remote status
• Opening/closing generating unit breakers
• Changing active power output of bus injection generation points
• Manual raise/lower of active power generation

Initializes the data used by the Power System Simulator and parameters required during a dynamic simulation, establishing the required data just prior to running a dynamic simulation.

Comprises programs sequentially scheduled by the DTS Simulator Executive (SIMXEC) every DTS simulation execution cycle, calculating and storing the solution of the simulated power system network model into the real-time database.

Represents boiler-turbine dynamics of coal or oil-fired drum types or once-through types. Includes:

• Steam valve dynamics
• Coordinated boiler-turbine controls
• Boiler controls
• Fuel system dynamics
• Feedwater system dynamics
• Off-nominal voltage and frequency effects
• Boiler dynamics
• Turbine dynamics

Key parameters include governor deadband (CYSO3), which represents the statistics of lumped units (0.1-20.0 MW). Deadband logic is bypassed if CYSO3 is zero.

2D table of frequency (per-unit) vs. voltage (per-unit) showing multiplier values (0.0-1.0).

The load demand error goes to the master controller, which changes the recirculation flow and simultaneously changes the setpoint of the pressure regulator within the turbine control. Valid for load demand errors less than 10% in magnitude.

The water starting time (Tw) is a function of the elevation of the turbine water supply. To avoid numerical instability when Tw approaches the one-second time step, a Z-form of the turbine model is used.

Key Parameters:

• CYP02 - Regulation/transient regulation ratio (0.0-1.0)
• CYP04 - Transient droop time constant (0.0-100.0 seconds)
• CYP08 - Water starting time (0.0-100.0 seconds)

Includes off-nominal voltage and frequency effects on auxiliary equipment (fuel handling and air atomizing system). The active power capability varies linearly with temperature.

Temperature model: MW capability = 1.0 + TCOEF × (1.0 - (ZNTEMP / TRATE))

Simulates prime mover dynamics with heat exchanger (HRSG). Three configurations:

• Unfired: Only exhaust gas heat source
• Fully fired: Exhaust preheats combustion air
• Parallel powered: HRSG supplies additional steam

Key equations: Te = Tf × [1 - (1 - 1/x) × Et] where x = (PRo × Wg)^((k-1)/k)

HRSG Model: Heat gained from heat exchanger: Hgm = Wg × Egm × (Te - Tm)

Steam generation Qsg follows heat flux Hgm with short lag due to metal heat capacitance MC and heat transfer film coefficient Ch.

Heat gain Hp = Ep × (K1 × Wg1 × [Te1 - Ti1] + ... + Ki × Wgi × [Tei - Tii])

Hp is input as additional heat to fuel system dynamics of fossil-fueled steam unit.

Only droop and turbine dynamics are included.

Key parameters:

• TTURBI - Turbine time constant (1.0-100.0 seconds)
• PMWMAX - Maximum power input to turbine

Two types of wind generators: Induction generators (IG) and Variable speed synchronous generators (SG).

Wind turbine parameters: RADIUS, CP (performance coefficient, 0.0-0.59, Betz limit = 0.59)

For variable CP: VWRATE, VWMIN, VWMAX, GEARAT, POLE

Induction generator: SK (critical slip), PK (critical power), R1, X1, XM, R2, X2

Reactive power calculation: Q = COEF0 + COEF1×P + COEF2×P² + COEF3×V + COEF4×V² (for IG)

Reactive power control: CTLTYP = "PF" (power factor), "Q" (reactive power), "NONE"

Zero value indicates no reclosure attempt at that stage.

To close breaker: Voltage below VSCHED - VRANGE/2, condition exists > TDCLOS, lockout expired, breaker in AUTO mode.

To open breaker: Voltage above VSCHED + VRANGE/2, condition exists > TDOPEN, breaker in AUTO mode.

Measurement point in SOANLG must have EQTYPE = 'BC'.

Tp = K / (Iⁿ - Ipⁿ) where:

• Tp = Operating time (seconds)
• K = Multiplier setting (from sample point)
• I = Current flow (MVA)
• Ip = Relay pickup current (MVA)
• n = Discrimination power (system constant)

If one bus is dead (zero voltage) and active bus passes VMGMIN/VMGMAX, breaker may close.

Values in MW/sec, increasing with pulse length.

Generic model data for boiler types: SUPOT, SUBOT, OFDRUM, CFDRUM, NRDRUM, UNFIRE.

FRQ01-FRQMM: Frequency values in per-unit Hz (decreasing order, 0.0-1.5)

KV01-KVNN: Voltage values in per-unit KV (decreasing order, 0.0-1.5)

AX0101-AXNNMM: Multiplier values (0.0-1.0) for fuel input (drum) or feedwater flow (once-through)

For IG: Q = COEF0 + COEF1×P + COEF2×P² + COEF3×V + COEF4×V²

For SG: Q = COEF0 + COEF1×P + COEF2×P² + COEF3×P³ + COEF4×P⁴

X1-Xn: MW breakpoints (must be monotonically increasing)

Y1-Yn: Heat rate values (MBtu/MWh, monotonically increasing)

FCOST: Fuel cost ($/MBtu)

COSTA: Fuel price adjustment factor (0-100%)

PENALT: Penalty factor (0.5-1.0)

Similar to SOFOGM with additional combined cycle parameters:

Same as SONUGU parameters (CYB02-CYB12, RCFLLM, RCFULM, RFAUX1-8).

Same as SOWDGU parameters for wind power models.

Piecewise linear approximation with SMP NMSCRS breakpoints.

Each hour's load = peak load × hourly factor.

Values are superimposed on constant hourly load, range -50.0 to 100.0.

Noise equation: noise = NAMPL × (STDEV×SQRT(-2×LOG(RAN1))×COS(6.2931854×RAN2)+MEAN)

Pdynamic = Σ { STn × (An + Bn × Xn) }

Pseudo tie line measurement = sum of component actual tie lines.

HISLOD = HL × (ISLOAD / LOADHL) where:

• HL - Load inertia constant (MW-sec/MVA) at LOADHL
• LOADHL - MW load value for HL

HISLAN = Sum of inertia constants for all generating units and BIGs in island

HTOT = HISLAN + HISLOD

Island frequency: ωt = ωt-Δt + (1/(2×HTOT)) × ∫(PACCEL/ωt-Δt) dt

Used to simulate plant auxiliary load when individual unit auxiliary loads are not available.

Up to 5 dynamic variables can be inserted into text description.

Scenario save case contains:

• Breaker status
• Generating unit control modes
• Interchange scheduling data
• Load data
• Scenario event file
• Load flow solution at start time

DSNAME - Data structure mnemonic to be saved

• Breaker status
• Generating unit control modes
• Reverting events
• Start variables for generator and dynamic models
• Relay status
• Acknowledged/unacknowledged alarms
• Copy of RTDB
• Dynamic Load Flow data
• AGC data
• DTS control parameters

DSNAME - Data structure mnemonic to be saved

DSNAME - Data structure mnemonic for PSDLF to be saved

DSNAME - Data structure mnemonic for PSGFDS to be saved

DSNAME - Data structure mnemonic for SSCR to be saved

DSNAME - Data structure mnemonic for PSSPRO to be saved

DSNAME - Data structure mnemonic for PSSSP to be saved

1. Transfer initialization load flow solution from DLF to DTS
2. Transfer load flow solution from DTS to DLF for modification
3. Transfer scenario event data to DTS run-time file
4. Complete simulation initialization

DSNAME - Data structure mnemonic to transfer between DLF and DTS modes

Analog value is integrated to simulate accumulator point.