A load control device may control the amount of power provided to an electrical load utilizing a phase control signal that operates in a reverse phase control mode, a center phase control mode, and a forward phase control mode. A load control device may be configured to determine that the electrical load should be operated via a phase control signal operating in a forward phase-control mode. After determining to operate the electrical load via the phase control signal in the forward phase-control mode, the load control device may provide the phase control signal in a reverse phase-control mode for a predetermined period of time to the electrical load, for example, to charge a bus capacitor of the electrical load. Subsequently, the load control device may be configured to switch the phase control signal to the forward phase-control mode and provide the phase control signal in the forward phase-control mode to the electrical load.

A load control device may control the amount of power provided to an electrical load utilizing a phase control signal that operates in a reverse phase control mode, a center phase control mode, and a forward phase control mode. A load control device may be configured to determine that the electrical load should be operated via a phase control signal operating in a forward phase-control mode. After determining to operate the electrical load via the phase control signal in the forward phase-control mode, the load control device may provide the phase control signal in a reverse phase-control mode for a predetermined period of time to the electrical load, for example, to charge a bus capacitor of the electrical load. Subsequently, the load control device may be configured to switch the phase control signal to the forward phase-control mode and provide the phase control signal in the forward phase-control mode to the electrical load.

A gyroscopic exercise apparatus, comprising: at least one control-moment gyroscope; at least one motion sensor for sensing movement of the apparatus; at least one spindle motor for providing rotation to a rotor of the gyroscope; and, at least one reversible motor for providing rotation to at least one gimbal of the gyroscope.

A gyroscopic exercise apparatus, comprising: at least one control-moment gyroscope; at least one motion sensor for sensing movement of the apparatus; at least one spindle motor for providing rotation to a rotor of the gyroscope; and, at least one reversible motor for providing rotation to at least one gimbal of the gyroscope.

A control unit controls an inverter circuit such that a positive voltage and a negative voltage are alternately applied to a primary winding. The control unit controls a cycloconverter so as to allow no power to be transmitted between the cycloconverter and the inverter circuit in a first period including an inversion period during which a voltage of the primary winding has its polarity inverted. The control unit also controls the cycloconverter so as to allow power to be transmitted either in a first direction from the cycloconverter toward the inverter circuit, or in a second direction opposite from the first direction, in a second period different from the first period.

A method of decoupled modulation of a direct AC/AC MMC between a first AC network having a first waveform and a second AC network having a second waveform, the MMC having a double-star topology with a plurality of phase legs, each phase leg having a first branch and a second branch, each of the first and second branches comprising a plurality of series connected bipolar cells. The method includes performing a first modulation based on a reference signal of the first AC network, independently of a reference signal of the second AC network, to generate, for each phase leg, a first integer command signal corresponding to a first combination of cell states in the first and second branches of the phase leg needed for generating the first waveform. The method also comprises performing a second modulation based on the reference signal of the second AC network, independently of the reference signal of the first AC network to generate, for each phase leg, a second integer command signal corresponding to a second combination of cell states in the first and second branches of the phase leg needed for generating the second waveform. The method also includes, based on the first and second integer command signals, mapping to each branch a number of cell states to be used for concurrently generating both the first and second waveforms, generating branch-level command signals to a capacitor voltage balancing algorithm. The method also includes, based on the mapping and the balancing algorithm, sending firing signals to the plurality of cells of each branch.

A method of decoupled modulation of a direct AC/AC MMC between a first AC network having a first waveform and a second AC network having a second waveform, the MMC having a double-star topology with a plurality of phase legs, each phase leg having a first branch and a second branch, each of the first and second branches comprising a plurality of series connected bipolar cells. The method includes performing a first modulation based on a reference signal of the first AC network, independently of a reference signal of the second AC network, to generate, for each phase leg, a first integer command signal corresponding to a first combination of cell states in the first and second branches of the phase leg needed for generating the first waveform. The method also comprises performing a second modulation based on the reference signal of the second AC network, independently of the reference signal of the first AC network to generate, for each phase leg, a second integer command signal corresponding to a second combination of cell states in the first and second branches of the phase leg needed for generating the second waveform. The method also includes, based on the first and second integer command signals, mapping to each branch a number of cell states to be used for concurrently generating both the first and second waveforms, generating branch-level command signals to a capacitor voltage balancing algorithm. The method also includes, based on the mapping and the balancing algorithm, sending firing signals to the plurality of cells of each branch.

A matrix converter system and control method includes a matrix converter, a generator, a plurality of output capacitors, and a controller. The matrix converter includes a plurality of switches and is connected between a multiphase input and a multiphase output. The plurality of output capacitors are connected between the multiphase output and ground. The generator is connected to the multiphase input and includes internal inductances. The controller is configured to control the plurality of switches to control active current and reactive current from the generator based on the internal inductances of the generator. The active and reactive currents are controlled to charge the plurality of output capacitors. The matrix converter operates in a current control mode and is able to boost output voltage above the input voltage level.

An energy control circuit is provided. The energy control circuit includes an input circuit; an output circuit; an energy storage circuit coupled between the input circuit and the output circuit; and a controller coupled to the input circuit and output circuit for controlling an amount of energy stored in the energy storage circuit and for controlling a waveform generated by the output circuit using energy stored in the energy storage circuit.

A matrix converter system and control method includes a matrix converter, a generator, a plurality of output capacitors, and a controller. The matrix converter includes a plurality of switches and is connected between a multiphase input and a multiphase output. The plurality of output capacitors are connected between the multiphase output and ground. The generator is connected to the multiphase input and includes internal inductances. The controller is configured to control the plurality of switches to control active current and reactive current from the generator based on the internal inductances of the generator. The active and reactive currents are controlled to charge the plurality of output capacitors. The matrix converter operates in a current control mode and is able to boost output voltage above the input voltage level.