A reactive power system comprises a plurality of electrical capacitor banks, with each electrical capacitor bank electrically connected in series with an electrical switch. The electrical switches may be electrically connected to a system such as, for example, an electrical induction motor starter system. A controller is coupled with the motor starter system and each of the electrical switches. The controller, in response to receiving a signal from the motor starter system, determines which of the plurality of electrical capacitor banks from which electrical power should be provided for the motor starter system. For the determined or identified electrical capacitor bank(s), the controller identifies the corresponding electrical switch(es) and communicates a signal to close the switch(es). Closing the switches results in the capacitors in the corresponding electrical capacitor banks to be electrically connected to the motor starter system and to provide current to the motor starter system.

A motor control system for induction-type capacitor-start AC electric motors having starting and run windings starts the electric motors on AC power then, without stopping the motor, switches to using a variable-frequency motor drive (VFD) configured with a maximum power point tracking method to run the motor from solar power. In particular embodiments, the MPPT method is adapted to reduce power consumed by the motor by reducing frequency and voltage provided by the VFD when available solar panel power is insufficient for full power operation, and to increase frequency and voltage provided by the VFD when available solar panel power is greater than power absorbed by the motor.

Included herein is a circuit comprising resistors, capacitors, relays, diode bridges, TRIACs, and DIACs mounted to a substrate. The circuit may be electrically connected to a user device containing a wide range of types and specifications of AC induction motors. The circuit may be installed plug-and-play onto a user device, without the need for tools, custom installation or deconstruction of a user device. Upon user direction or automatically, the circuit may inject DC current into the user tool which generates a stationary magnetic field inside the AC induction motor causing deceleration/arrestment of the AC induction motor's rotor. The circuit may prevent unintended acceleration of the rotor upon powering on the user device. Also included is a method for prevention of unintended acceleration of the rotor upon powering on the user device. Also included is a method for decelerating/arresting an AC induction motor.

A drive circuit for an electric motor includes a first filter, a rectifier, an inverter, and a line contactor. The first filter is configured to be coupled to an AC source and produces a filtered line frequency AC signal. The rectifier is coupled to the filter and produces a DC signal from the filtered line frequency AC signal. The inverter is coupled to the rectifier and produces an AC signal on an output node of the inverter. The AC signal is supplied to the electric motor to energize its stator windings. The line contactor is coupled between an output node of the first filter and the output node of the inverter. The line contactor supplies the output node of the inverter directly with the filtered line frequency AC signal to energize the stator windings when the inverter is disabled.

A reactive power system comprises a plurality of electrical capacitor banks, with each electrical capacitor bank electrically connected in series with an electrical switch. The electrical switches may be electrically connected to a system such as, for example, an electrical induction motor starter system. A controller is coupled with the motor starter system and each of the electrical switches. The controller, in response to receiving a signal from the motor starter system, determines which of the plurality of electrical capacitor banks from which electrical power should be provided for the motor starter system. For the determined or identified electrical capacitor bank(s), the controller identifies the corresponding electrical switch(es) and communicates a signal to close the switch(es). Closing the switches results in the capacitors in the corresponding electrical capacitor banks to be electrically connected to the motor starter system and to provide current to the motor starter system.

This electric hoisting machine comprises: a motor driven by single-phase current; a cylindrical motor housing; a starting capacitor; a operating capacitor; a starting capacitor disconnecting switch; a control unit which controls the operation of the motor and which is covered by a control housing; and a housing case in which small-diameter cylindrical portions for accommodating the starting capacitor, a large-diameter cylindrical portion for accommodating the operating capacitor, and a large-diameter cylindrical portion for accommodating the starting capacitor disconnecting switch are integrally provided in a state of continuing in a horizontal row, the housing case being mounted on the outer periphery of the motor housing in such a manner that the cylindrical portions are oriented parallel to a rotation axis.

A fan controller for a ceiling fan is provided. The fan controller includes one or more switching devices configured to selectively couple the ceiling fan to a power source. The fan controller includes a first capacitor having a first capacitance and a second capacitor having a second capacitance that is larger than the first capacitance. The fan controller includes a power meter circuit and one or more control devices. The one or more control devices are configured to obtain, via the power meter circuit, data indicative of electrical power a fan motor of the ceiling fan draws from the power source. The one or more control devices are configured determine a size of the fan motor based on the data. The one or more control devices are configured to select the first capacitor or the second capacitor as a selected capacitor based on the determined size of the fan motor.

A hard start capacitor replacement unit has a plurality of capacitors in a container sized to fit in existing hard start capacitor space. The capacitors are 4 metallized film capacitors wound in a single cylindrical capacitive element. The container has a common terminal and capacitors value terminals for the plurality of capacitors, which may be connected singly or in combination to provide a selected capacitance. An electronic or other relay connects the selected capacitance in parallel with a motor run capacitor. The hard start capacitor replacement unit is thereby adapted to replace a wide variety of hard start capacitors.

A drive circuit for an electric motor includes a first filter, a rectifier, an inverter, and a line contactor. The first filter is configured to be coupled to an AC source and produces a filtered line frequency AC signal. The rectifier is coupled to the filter and produces a DC signal from the filtered line frequency AC signal. The inverter is coupled to the rectifier and produces an AC signal on an output node of the inverter. The AC signal is supplied to the electric motor to energize its stator windings. The line contactor is coupled between an output node of the first filter and the output node of the inverter. The line contactor supplies the output node of the inverter directly with the filtered line frequency AC signal to energize the stator windings when the inverter is disabled.

A fan controller for a ceiling fan is provided. The fan controller includes one or more switching devices configured to selectively couple the ceiling fan to a power source. The fan controller includes a first capacitor having a first capacitance and a second capacitor having a second capacitance that is larger than the first capacitance. The fan controller includes a power meter circuit and one or more control devices. The one or more control devices are configured to obtain, via the power meter circuit, data indicative of electrical power a fan motor of the ceiling fan draws from the power source. The one or more control devices are configured determine a size of the fan motor based on the data. The one or more control devices are configured to select the first capacitor or the second capacitor as a selected capacitor based on the determined size of the fan motor.