An example apparatus for charge neutralization includes: a first emitter nozzle; a power supply configured to supply a high frequency alternating current (AC) signal to the first emitter nozzle; control circuitry configured to: provide a polarity signal to the power supply to generate a DC offset signal, wherein a combination of the high frequency AC signal and the DC offset signal causes the power supply to output a positive ion generation pulse or a negative ion generation pulse; control the polarity signal to cause the power supply to provide a period of positive ion generation and a period of negative ion generation; determine a balance voltage at an output of the first emitter nozzle; and control the polarity signal to adjust a relative durations of the period of positive ion generation and the period of negative ion generation based on the balance voltage.

A system and method for detecting resonant frequency of a corona igniter concurrent with operation of the corona igniter is provided. The method includes providing a plurality of pulses of energy to the corona igniter, each having a pulse duration and spaced from one another by a deadtime duration during which no energy is provided to the corona igniter. Each pulse duration is ceased before current flowing in the corona igniter crosses zero, and each zero crossing of the current occurs during one of the deadtime durations. The next pulse of energy is provided to the corona igniter in response to the zero crossing of the current. A resonant frequency value is then obtained based on a sum of the pulse and deadtime durations of two consecutive cycles, or the time between zero crossings. The resonant frequency values become more accurate over time, and the drive frequency is adjusted accordingly.

A system and method for detecting resonant frequency of a corona igniter concurrent with operation of the corona igniter is provided. The method includes providing a plurality of pulses of energy to the corona igniter, each having a pulse duration and spaced from one another by a deadtime duration during which no energy is provided to the corona igniter. Each pulse duration is ceased before current flowing in the corona igniter crosses zero, and each zero crossing of the current occurs during one of the deadtime durations. The next pulse of energy is provided to the corona igniter in response to the zero crossing of the current. A resonant frequency value is then obtained based on a sum of the pulse and deadtime durations of two consecutive cycles, or the time between zero crossings. The resonant frequency values become more accurate over time, and the drive frequency is adjusted accordingly.

Described herein are plasma generation devices and methods of use of the devices. The devices can be used for the cleaning of various surfaces and/or for inhibiting or preventing the accumulation of particulates, such as dust, or moisture on various surfaces. The devices can be used to remove dust and other particulate contaminants from solar panels and windows, or to avoid or minimize condensation on various surfaces. In an embodiment a plasma generation device is provided. The plasma generation device can comprise: a pair of electrodes positioned in association with a surface of a dielectric substrate. The pair of electrodes can comprise a first electrode and a second electrode. The first electrode and second electrode can be of different sizes, one of the electrodes being smaller than the other of the electrodes. The first electrode and second electrode can be separated by a distance and electrically connected to a voltage source.

An electrohydrodynamic heat sink is provided which has a base electrode receiving heat from a heat source to be dissipated, the base electrode having a shape that converges with a cavity wherein a fluid is placed during use, and a ring electrode which is arranged in the cavity of the base electrode, the ring electrode being connected to an electric power source (P.S) in order to ionise the fluid of the base electrode and generate an ion wind (w) from the ring electrode to the base electrode, so as to generate a laminar current of the fluid in order to discharge the heat from the cavity.

An electrohydrodynamic heat sink is provided which has a base electrode receiving heat from a heat source to be dissipated, the base electrode having a shape that converges with a cavity wherein a fluid is placed during use, and a ring electrode which is arranged in the cavity of the base electrode, the ring electrode being connected to an electric power source (P.S) in order to ionise the fluid of the base electrode and generate an ion wind (w) from the ring electrode to the base electrode, so as to generate a laminar current of the fluid in order to discharge the heat from the cavity.

An insulator for a corona igniter, referred to as a barrier discharge ignition (BDI) device, for use in an internal combustion engine, is provided. A central electrode is disposed in a slot of the insulator and an electrode tip is spaced from a round insulator tip by insulating material. A shell formed of metal surrounds a portion of the insulator. The insulator has a thickness tapering between a shell firing surface and the insulator tip. The tapering insulator thickness is unidirectional and thus does not increase between a start of the taper and the insulator tip. A method of manufacturing an insulator for a corona igniter is also provided. Equations can be used to determine if a taper in the insulator thickness is needed to encourage corona propagation along a core nose projection of the insulator, and if so, the location and size of the taper.

An insulator for a corona igniter, referred to as a barrier discharge ignition (BDI) device, for use in an internal combustion engine, is provided. A central electrode is disposed in a slot of the insulator and an electrode tip is spaced from a round insulator tip by insulating material. A shell formed of metal surrounds a portion of the insulator. The insulator has a thickness tapering between a shell firing surface and the insulator tip. The tapering insulator thickness is unidirectional and thus does not increase between a start of the taper and the insulator tip. A method of manufacturing an insulator for a corona igniter is also provided. Equations can be used to determine if a taper in the insulator thickness is needed to encourage corona propagation along a core nose projection of the insulator, and if so, the location and size of the taper.

An airflow generation device having a first dielectric substrate made from a rubber elastic material, a first electrode on or near by a first surface of the first dielectric substrate, a second electrode on a second surface, and a second dielectric substrate made from a rubber elastic material covering the second electrode. It makes the airflows generated by plasma caused from partial gas near by the first surface through applied voltage into the first electrode and the second electrode, and bonding portions between the first electrode and the second electrode and the first dielectric substrate, bonding portions between the second electrode and the second dielectric substrate, and bonding portions between the first dielectric substrate and the second dielectric substrate are bonded by chemical bonds with chemically crosslinking.

A vehicular static eliminating device includes: a negative ion generating device; and a guide device configured to guide negative ions and release the negative ions from an emission port to a static elimination target spot which is positively charged, the guide device including: a guide member defining a passage through which to guide the negative ions, the guide member being made of a resin which is easily negatively charged in a triboelectric series; and a tip-shaped part configured to discharge, by corona discharge, negative electric charges, which have accumulated on the guide member, to the static elimination target spot, the tip-shaped part being provided in a part defining the emission port and in proximity to the static elimination target spot.