Control Algorithms

Control Algorithms

NexusEdge includes 42 deterministic control algorithms plus AI-advisory (MPC).

Core Algorithms

Algorithm	ID	Description
TMC	tmc	Thermal Momentum Control — piecewise proportional with momentum tracking
PID	pid	Standard PID with anti-windup and bumpless transfer
On/Off	on_off	Bang-bang with configurable deadband and min-on/min-off timers
Linear	linear	Linear proportional 0-100%
Cascade	cascade	Outer/inner loop cascade controller

Equipment-Specific TMC Variants

Algorithm	Equipment
tmc_ahu	AHU (2/4-pipe with economizer)
tmc_ahu_lead_lag	AHU 4-pipe with lead/lag pumps
tmc_vav	VAV box
tmc_vav_dx	VAV with DX compressor
tmc_chiller	Chiller with lockout
tmc_chiller_simple	Simplified chiller
tmc_comfort_boiler	Comfort heating boiler
tmc_domestic_boiler	Domestic hot water boiler
tmc_steambundle	Steam bundle heat exchanger
tmc_doas_changeover	DOAS with DX + season relay
tmc_doas_dx	Direct-fired DOAS + DX
tmc_electric_heat	Electric heat only
tmc_greenhouse	Greenhouse climate control
tmc_natatorium	Pool/natatorium dehumidification
tmc_zone_reheat	Zone reheat controller

Lead/Lag Algorithms

Algorithm	Equipment
lead_lag_pump	Lead/lag pumps (HW, CW, circ)
lead_lag_boiler	Lead/lag boilers
lead_lag_chiller	Lead/lag chillers

Specialty Algorithms

Algorithm	Description
pressure_booster	VFD pressure booster with deadband
cascade_boiler	Multi-boiler cascade plant
water_cooled_chiller	Water-cooled chiller + condenser
dx_cw_ahu	DX + chilled water AHU
fan_coil	2-way / 4-way fan coil
rtu	Rooftop unit
heat_pump	Commercial heat pump
resi_heat_pump	Residential heat pump
resi_boiler	Residential boiler
resi_furnace	Residential furnace
vfd_pump_pack	Multi-VFD pump pack
cooling_tower	VFD cooling tower
pool_gas_heater	Pool gas heater
pool_heat_pump	Pool heat pump
water_monitor_city	City water monitor
water_monitor_well	Well water monitor
electrical_monitor	Electrical load monitor
commercial_lighting	Commercial lighting + power
smart_garden	Smart garden / irrigation
smart_home	Smart home controller
mpc_advisory	Model Predictive Control (advisory, non-controlling)

TMC (Thermal Momentum Control)

TMC is NexusEdge's signature algorithm. Unlike PID, TMC uses a piecewise-linear response curve based on the temperature delta from setpoint, with momentum tracking to prevent overshoot. Key parameters:

• setpoint — Target temperature
• deadband — No-action zone around setpoint
• oar_sp_hi / oar_sp_lo — Outdoor air reset setpoint range
• high_temp_limit / low_temp_limit — Safety limits
• mode_lockout — Season lockout (summer/winter)

Published research: Andrew Jewell Sr. (ORCID: 0009-0005-2158-7060)