An induction heat cooking apparatus that includes: a rectifier that is configured to convert alternating current (AC) voltage supplied from an external power source into direct current (DC) voltage; an inverter that is configured to generate current based on DC voltage received from the rectifier and provide the current to output nodes; heating coils that are configured to, based on the current generated by the inverter, generate magnetic fields for providing heat; a first capacitive unit that includes one or more resonance capacitors and that is coupled between the output nodes; a second capacitive unit that includes one or more wireless power transfer (WPT) capacitors and that is configured to be coupled between the output nodes; and a mode conversion switch that is configured to couple the second capacitive unit to the first capacitive unit in parallel is disclosed.

A discrete field coupled capacitor with a cross-connected capacitor-pair, such as for use as a discrete bypass capacitor. The FCC includes a first port with first and second terminals, and a second port with third and fourth terminals. A first capacitor structure is connected between the first and second terminals, and a second capacitor structure connected between the third and fourth terminals. A cross-connect structure includes a first cross-connection to connect the first terminal to the third terminal, and a second cross-connection to connect the second terminal to the fourth terminal, to cross-connect the first and second capacitor structures. The capacitor structures have respective parasitic ESL, and can be disposed in proximity to effect a pre-defined ESL field coupling with reverse phasing to reduce parasitic ESL. The FCC can be constructed as a PCB or monolithic device. In a PCB four-layer construction, the cross-connections can be formed on respective mid-layers.

A discrete field coupled capacitor with a cross-connected capacitor-pair, such as for use as a discrete bypass capacitor. The FCC includes a first port with first and second terminals, and a second port with third and fourth terminals. A first capacitor structure is connected between the first and second terminals, and a second capacitor structure connected between the third and fourth terminals. A cross-connect structure includes a first cross-connection to connect the first terminal to the third terminal, and a second cross-connection to connect the second terminal to the fourth terminal, to cross-connect the first and second capacitor structures. The capacitor structures have respective parasitic ESL, and can be disposed in proximity to effect a pre-defined ESL field coupling with reverse phasing to reduce parasitic ESL. The FCC can be constructed as a PCB or monolithic device. In a PCB four-layer construction, the cross-connections can be formed on respective mid-layers.

A power supply circuit comprises a push-pull portion that includes a transformer (T1) having a primary winding with first and second terminals connected to ground via a first and second switches respectively. The push-pull portion generates an output voltage (V.sub.out) across the secondary winding. An inductor (L1) is connected between an input voltage (V.sub.in) and a centre tap on the primary winding of the transformer (T1) such that a boost voltage (V.sub.boost) is applied to the centre tap. A two input charge pump has its two inputs connected to the first and second terminals of the primary winding. The charge pump generates a charging voltage (V.sub.rect) at its output terminal that is greater than the boost voltage (V.sub.boost). An energy storage portion is connected to the output of the charge pump and is arranged to supply a hold-up voltage (V.sub.holdup) when the input voltage (V.sub.in) is below a threshold value.

A power supply circuit comprises a push-pull portion that includes a transformer (T1) having a primary winding with first and second terminals connected to ground via a first and second switches respectively. The push-pull portion generates an output voltage (V.sub.out) across the secondary winding. An inductor (L1) is connected between an input voltage (V.sub.in) and a centre tap on the primary winding of the transformer (T1) such that a boost voltage (V.sub.boost) is applied to the centre tap. A two input charge pump has its two inputs connected to the first and second terminals of the primary winding. The charge pump generates a charging voltage (V.sub.rect) at its output terminal that is greater than the boost voltage (V.sub.boost). An energy storage portion is connected to the output of the charge pump and is arranged to supply a hold-up voltage (V.sub.holdup) when the input voltage (V.sub.in) is below a threshold value.

Multiphase electromagnetic machines, such as free-piston engines or compressors, may require, or supply, a pulsed power profile from or to a DC bus, respectively. The pulsed power profile may include relatively large fluctuations in instantaneous power. Sourcing, sinking, or otherwise exchanging power with an AC grid, via an inverter, may be accomplished by using an energy storage device and a DC-DC converter coupled to a DC bus. The energy storage device may aid in smoothing the pulsed power profile, while the DC-DC converter may aid in reducing fluctuations in voltage across a DC bus due to energy storage in the energy storage device.

Multiphase electromagnetic machines, such as free-piston engines or compressors, may require, or supply, a pulsed power profile from or to a DC bus, respectively. The pulsed power profile may include relatively large fluctuations in instantaneous power. Sourcing, sinking, or otherwise exchanging power with an AC grid, via an inverter, may be accomplished by using an energy storage device and a DC-DC converter coupled to a DC bus. The energy storage device may aid in smoothing the pulsed power profile, while the DC-DC converter may aid in reducing fluctuations in voltage across a DC bus due to energy storage in the energy storage device.

A motor drive system includes a converter configured to convert power between AC power in a power source and DC power in a DC link, an inverter for drive configured to convert power between the DC power and AC power in a servomotor for drive, a motor control unit for drive configured to control the servomotor for drive, a power storage device configured to store the DC power from the DC link or supplies the DC power to the DC link, and a determination unit configured to determine whether the holding energy of the power storage device is lower than a threshold for energy shortage determination, wherein when the holding energy is lower than the threshold for energy shortage determination, the motor control unit for drive controls the servomotor for drive by setting an additional standby period in which the servomotor for drive is inactive in a predetermined operation pattern.

A motor drive system includes a converter configured to convert power between AC power in a power source and DC power in a DC link, an inverter for drive configured to convert power between the DC power and AC power in a servomotor for drive, a motor control unit for drive configured to control the servomotor for drive, a power storage device configured to store the DC power from the DC link or supplies the DC power to the DC link, and a determination unit configured to determine whether the holding energy of the power storage device is lower than a threshold for energy shortage determination, wherein when the holding energy is lower than the threshold for energy shortage determination, the motor control unit for drive controls the servomotor for drive by setting an additional standby period in which the servomotor for drive is inactive in a predetermined operation pattern.

A voltage generator circuit can be structured to provide an output voltage having a substantially flat temperature coefficient by use of a circuit loop having transistors and a resistor arranged such that, in operation, current through the resistor has a signed temperature coefficient. The current behavior can be controlled by an output transistor coupled to another transistor, which is coupled to the circuit loop, with this other transistor sized such that, in operation, a voltage of this other transistor has a signed temperature coefficient that is opposite in sign to the signed temperature coefficient of the current through the resistor. Embodiments of voltage generator circuits can also include additional components to trim output voltage, to provide unconditional stability, or other features for the respective voltage generator circuit. In various embodiments, a voltage generator circuit can be implemented as a low drop-out (LDO) voltage regulator.