Motors & Drives
Every motors & drives calculator on CalcEngines — unit converters, derived indices and interpretive tools, each with its formula, a worked example and the reference intervals it is judged against.
14 calculators in this section
- BLDC Inverter Loss CalculatorLosses in a three-phase, six-MOSFET motor inverter with sinusoidal phase current: conduction, switching and dead-time diode losses per device and in total, and the inverter's efficiency at your output power.
- BLDC Motor Torque-Speed Envelope CalculatorThe motor sizing plot: the continuous and peak torque a brushless machine and its drive can hold at every speed, your load curve drawn on the same axes, and the speed where the two cross — which is where the machine will actually settle. Below base speed the drive holds rated torque and is limited by current; above it the back-EMF has reached the available bus voltage and torque falls.
- DC Motor Calculator (Back-EMF, Kv and Torque)The brushed permanent-magnet motor from first principles: back-EMF from speed, current from what is left of the supply, torque from current, and where that leaves mechanical power, copper loss and efficiency — plus the stall and no-load points and the straight line between them, with Kv and Kt shown to be the same constant.
- E-Bike Range CalculatorHow far an e-bike battery goes, built from the physics rather than a lookup: rolling resistance, aerodynamic drag and gradient worked out separately, divided by the drive efficiency, and turned into watt-hours per kilometre and a range — with the split shown, because at 25 km/h the air is taking most of it.
- Electromechanical Actuator Load Locus CalculatorSize a linear electromechanical actuator against a sinusoidal command. The page sweeps one whole cycle, adds up the five torques the actuator has to fight, reflects them through the screw to the motor shaft, and plots the trajectory of motor torque against motor speed — the load locus. The headline is whether that locus fits inside the motor and drive's envelope and by how much at its worst point, with the five contributions at that point broken out, because reflected inertia is usually the one that decides the answer.
- Gear Ratio CalculatorOverall ratio, output speed and output torque for one, two or three gear or belt stages, with the per-stage efficiency taken off, the speed and torque at every intermediate shaft, and the load inertia reflected back through the ratio — which falls with its square, and is the real reason a gearbox makes a load easier to accelerate.
- Induction Motor Slip CalculatorSynchronous speed from the supply frequency and the pole count, then the slip, the slip speed and the rotor frequency from the speed on your nameplate — with a check on whether it looks right.
- Induction Motor Torque-Speed Curve CalculatorThe whole torque-speed curve of a cage or wound-rotor induction machine from its equivalent-circuit parameters: starting torque, the pull-up through the middle, the breakdown torque and the slip it sits at, and the short stable stretch between breakdown and synchronous speed where the machine actually runs. With your load line on the same axes, and what reduced voltage does to all of it.
- Motor Full Load Current CalculatorFull-load amps from a motor's nameplate kW or HP, with efficiency and power factor in the right places — plus the starting current direct-on-line and star-delta, and the kVA it all adds up to.
- Motor Power, Torque and Speed CalculatorAny two of shaft power, torque and speed give the third — in kW, HP, N·m, kgf·m, lb·ft, rpm or rad/s — plus the electrical power the motor has to draw to produce them.
- Pump and Fan System Curve CalculatorWhere a pump or fan actually operates: its own head-flow curve crossed with the system's resistance curve, and the duty point where the two meet. Then the comparison that pays for the page — what it costs to trim the flow with a throttle valve against what it costs to trim it with a variable speed drive, computed from your own curves rather than asserted from the affinity laws.
- Pump Motor Power CalculatorHydraulic power, shaft power, motor input power, current and running cost from the flow and head your pump has to deliver — in L/min, L/s, m³/h or gpm, with head in metres or feet.
- Regenerative Braking CalculatorWhat happens when a motor becomes a generator: the braking torque and power, the energy that arrives back on the DC bus once both efficiencies are counted, the bus voltage rise that energy causes in the link capacitance — which is what trips an over-voltage fault — and the brake resistor you need when the bus cannot absorb it. The fraction actually recovered is always less than people expect.
- Stepper Motor Speed, Torque and Steps CalculatorSteps per revolution, rpm and the linear travel per step for a leadscrew or a belt — the steps-per-millimetre figure every 3D printer and CNC build needs — plus the corner speed where the winding's inductance stops the current reaching its setpoint and the torque starts to fall away.