Described is a supply circuit for a corona ignition device, with an input for connection to a direct voltage source, a first converter, a second converter, and an output for connecting a load. The two converters each generate an output voltage, which is provided on its secondary side and exceeds the input voltage. The two converters each contain a transformer that galvanically separates the primary side of the converter from its secondary side. At least one transistor switch is arranged between the input and primary side of the two converters for pulse width-modulation of the input voltage. The primary side of the second converter is connected in parallel with the primary side of the first converter, the secondary side of the second converter is connected in series with the secondary side of the first converter, the secondary sides of the two converters are each bridged in this series connection by at least one diode, so that an output voltage can be provided at the output of the supply circuit even given a failure of one of the two converters.

Described is a supply circuit for a corona ignition device, with an input for connection to a direct voltage source, a first converter, a second converter, and an output for connecting a load. The two converters each generate an output voltage, which is provided on its secondary side and exceeds the input voltage. The two converters each contain a transformer that galvanically separates the primary side of the converter from its secondary side. At least one transistor switch is arranged between the input and primary side of the two converters for pulse width-modulation of the input voltage. The primary side of the second converter is connected in parallel with the primary side of the first converter, the secondary side of the second converter is connected in series with the secondary side of the first converter, the secondary sides of the two converters are each bridged in this series connection by at least one diode, so that an output voltage can be provided at the output of the supply circuit even given a failure of one of the two converters.

A method of providing spark ignition for an engine or other equipment having a combustion chamber. A radio frequency wave or a microwave (RF/microwave) generator delivers radio frequency waves or microwaves to a transmit antenna inside the combustion chamber. At least one RF/microwave receive antenna is attached to an internal surface of the combustion chamber and comprises two or more RF/microwave focusing features with a spark gap between them. The transmit antenna wirelessly energizes the receive antenna, which generates a spark between the two focusing features.

A method of providing spark ignition for an engine or other equipment having a combustion chamber. A radio frequency wave or a microwave (RF/microwave) generator delivers radio frequency waves or microwaves to a transmit antenna inside the combustion chamber. At least one RF/microwave receive antenna is attached to an internal surface of the combustion chamber and comprises two or more RF/microwave focusing features with a spark gap between them. The transmit antenna wirelessly energizes the receive antenna, which generates a spark between the two focusing features.

A method of providing spark ignition for an engine or other equipment having a combustion chamber. A radio frequency wave or a microwave (RF/microwave) generator delivers radio frequency waves or microwaves to a transmit antenna inside the combustion chamber. At least one RF/microwave receive antenna is attached to an internal surface of the combustion chamber and comprises two or more RF/microwave focusing features with a spark gap between them. The transmit antenna wirelessly energizes the receive antenna, which generates a spark between the two focusing features.

A method of providing spark ignition for an engine or other equipment having a combustion chamber. A radio frequency wave or a microwave (RF/microwave) generator delivers radio frequency waves or microwaves to a transmit antenna inside the combustion chamber. At least one RF/microwave receive antenna is attached to an internal surface of the combustion chamber and comprises two or more RF/microwave focusing features with a spark gap between them. The transmit antenna wirelessly energizes the receive antenna, which generates a spark between the two focusing features.

An ignition system (10) comprises a high voltage transformer (12) comprising a primary winding (12.1) and a secondary winding (12.2). A primary resonant circuit (26) is formed by the primary winding (12.1) and a primary circuit capacitance (24). A secondary resonant circuit (16) is formed by an ignition plug (14), as a load, the secondary winding (12.2); the ignition plug (14) being represented by a secondary circuit capacitance (18) and a secondary circuit load resistance (Rp) put in parallel. Said load resistance value varies during an ignition cycle. The primary resonant circuit (26) and the secondary resonant circuit (16) have a common mode resonance frequency (f.sub.c) and a differential mode resonance frequency (f.sub.d). A controller (28) is configured to cause a drive circuit (22) to drive the primary winding at a frequency, which is either the common-mode resonance frequency (f.sub.c) or the differential mode resonance frequency (f.sub.d) and is connected to a feed-back circuit (50) to adapt the frequency of the primary winding to the variable load resistance.

An ignition system (10) comprises a high voltage transformer (12) comprising a primary winding (12.1) and a secondary winding (12.2). A primary resonant circuit (26) is formed by the primary winding (12.1) and a primary circuit capacitance (24). A secondary resonant circuit (16) is formed by an ignition plug (14), as a load, the secondary winding (12.2); the ignition plug (14) being represented by a secondary circuit capacitance (18) and a secondary circuit load resistance (Rp) put in parallel. Said load resistance value varies during an ignition cycle. The primary resonant circuit (26) and the secondary resonant circuit (16) have a common mode resonance frequency (f.sub.c) and a differential mode resonance frequency (f.sub.d). A controller (28) is configured to cause a drive circuit (22) to drive the primary winding at a frequency, which is either the common-mode resonance frequency (f.sub.c) or the differential mode resonance frequency (f.sub.d) and is connected to a feed-back circuit (50) to adapt the frequency of the primary winding to the variable load resistance.

An ignition unit improves an air-fuel-ratio, i.e., good mileage and lean burn without changing a gasoline engine structure significantly. The ignition unit comprises a discharge device including a booster and a discharger provided at an output side of the booster, the booster having a resonance structure configured to boost the electromagnetic wave inputted from the electromagnetic wave oscillator so as to cause a discharge from the discharger, and an electromagnetic wave emitter electrically connected to the electromagnetic wave oscillator and configured to emit the electromagnetic wave inputted from the electromagnetic wave oscillator. Moreover, the ignition unit further includes a housing part including a first hole into which the discharge device is inserted and a second hole into which the electromagnetic wave emitter is inserted such that the housing part houses therein both the discharge device and the electromagnetic wave emitter, and the housing part can be inserted into a single hole of a cylinder head of an internal combustion engine.

A compression-ignition type internal combustion engine that burns a gaseous fuel, improves an ignition performance not only at a center part of the combustion chamber but also at an outer edge part. The compression-ignition engine comprises an electromagnetic wave generator configured to generate an electromagnetic wave, a controller configured to control the electromagnetic wave generator, and a plasma generator comprising a boosting circuit that constitutes a resonator configured to boost the electromagnetic wave, a first electrode configured to receive an output from the boosting circuit, and a second electrode provided to a vicinity of the first electrode, and the plasma generator is configured such that the first electrode is extruded and exposed toward a combustion chamber of the internal combustion engine, and a plurality of plasma generators are provided.