Abstract: A corona ignition system for igniting fuel in a combustion chamber of an internal combustion engine, comprising a oscillating circuit, which contains an ignition electrode, a high-frequency generator, which is connected to the oscillating circuit, in order to produce an AC voltage to excite the oscillating circuit, a converter in order to produce an input voltage for the high-frequency generator from an on-board supply voltage, a voltage controller to stabilize the input voltage produced by the converter for the high-frequency generator, and a control unit for controlling the high-frequency generator, wherein the control unit communicates an imminent load change of the converter to the voltage regulator, before the load change occurs as a result of activation or deactivation of the high-frequency generator. A method for controlling a corona ignition system is also described.

Abstract: A method for setting adjusting frequency of an electric oscillating circuit of a corona ignition device. The circuit is excited with a starting value (f1) of the excitation frequency and a reference value (IR) of a frequency-dependent variable is measured. The excitation frequency is incrementally changed. After every increment a value (I) of the frequency-dependent variable is measured and it is determined whether the measured value (I) deviates significantly from the reference value (IR). Depending upon the measured value (I) relative to the reference value, the value (f) of the excitation frequency is either set as the new starting value (f1) or stored as a boundary value. Further incremental changes to the excitation frequency are made in one of two directions and further comparisons of the values I and IR are performed. Ultimately, the excitation frequency can be set to a mean value between first and second boundary values.

Abstract: A method for controlling a corona ignition device, which comprises an ignition electrode, at which a corona discharge is produced, a resonating circuit, which contains the ignition electrode, and a high-frequency generator connected to the resonating circuit, wherein the resonating circuit is excited with an AC voltage (Ui) produced by the high-frequency generator, the frequency of said voltage being specified by a control signal (Ud) applied across the high-frequency generator, the frequency of the control signal (Ud) is changed as the control variable of a control circuit, and the phase position between the current (Ii) flowing in the resonating circuit and a voltage signal is regulated to a target value, characterised in that the target value is changed during the operation of the corona ignition device. A corona ignition device for igniting fuel in a combustion chamber of an internal combustion engine is also described.

Abstract: A corona ignition system for igniting fuel in a combustion chamber of an internal combustion engine, comprising a oscillating circuit, which contains an ignition electrode, a high-frequency generator, which is connected to the oscillating circuit, in order to produce an AC voltage to excite the oscillating circuit, a converter in order to produce an input voltage for the high-frequency generator from an on-board supply voltage, a voltage controller to stabilize the input voltage produced by the converter for the high-frequency generator, and a control unit for controlling the high-frequency generator, wherein the control unit communicates an imminent load change of the converter to the voltage regulator, before the load change occurs as a result of activation or deactivation of the high-frequency generator. A method for controlling a corona ignition system is also described.

Abstract: A method for setting adjusting frequency of an electric oscillating circuit of a corona ignition device. The circuit is excited with a starting value (f1) of the excitation frequency and a reference value (IR) of a frequency-dependent variable is measured. The excitation frequency is incrementally changed. After every increment a value (I) of the frequency-dependent variable is measured and it is determined whether the measured value (I) deviates significantly from the reference value (IR). Depending upon the measured value (I) relative to the reference value, the value (f) of the excitation frequency is either set as the new starting value (f1) or stored as a boundary value. Further incremental changes to the excitation frequency are made in one of two directions and further comparisons of the values I and IR are performed. Ultimately, the excitation frequency can be set to a mean value between first and second boundary values.

Abstract: A method for controlling a glow plug in a diesel engine, in particular in the preheating phase, is described. According to the invention, it is provided that the time gradient of an electrical variable which varies according to the temperature of the glow plug is measured and compared with a threshold value, and when said time gradient exceeds or drops below the threshold value, the electric supply voltage of the glow plug is changed.

Abstract: A method for tracking defective functions in the operation of heater plugs in a diesel engine of a vehicle, provided with a control unit for the control of its heater plugs—the preheater control unit—, by monitoring at least one operating parameter of the heater plugs and/or of the preheater control unit, generating a fault message when the operation parameter so monitored deviates from a predefined nominal value or nominal state of the operating parameter, and storing the fault message. The invention links the fault message to a time parameter, stores the fault message together with the time parameter, searches for further fault messages that are stored in the vehicle and linked to the same time parameter, and combines the fault messages that are linked to the same time parameter.

Abstract: The invention relates to a method for supplying current to a glow plug in a running diesel engine after reaching the operating temperature thereof by a series of current pulses, wherein a piston of the engine carries out a work cycle comprising several strokes and the glow plug is supplied with current as a function of the strokes of the work cycle such that the electric current supplied in each work cycle is mainly supplied at a predetermined, steady stroke of the piston, wherein control time intervals that follow each other are defined, during which up to two switching processes can be triggered by a control device, by which the glow plug can be connected to a voltage source for creating a current pulse or can be disconnected from the voltage source for ending a current pulse. According to the invention, the control time intervals have a duration that can be varied by the control device as a function of the rotational speed of the engine.

Abstract: The invention relates to a method for operating a glow plug with the engine running, wherein an effective voltage is generated from a vehicle electrical system voltage by pulse width modulation, the effective voltage is applied to the glow plug and changed as a function of engine parameters, a target value of the effective voltage that is dependent on the engine parameters and to which the effective voltage is changed is specified, a maximum increment for a change of the actual value of the effective voltage in at least one direction is specified, and a change of the actual value in at least one direction to a target value that deviates from the actual value by more than the maximum increment is carried out in several steps. The invention further relates to a controller which carries out such a method during operation.

Abstract: A method for determining a heating characteristic of a glow plug, wherein pulse-width-modulated voltage pulses are applied to the glow plug and an electric variable is measured repeatedly during a voltage pulse with the heating characteristic of the glow plug determined by evaluating the difference of successive measurement results of this variable.

Abstract: Herein is described a method for the heating-up of a ceramic glow plug by applying a variable electric voltage to the glow plug. In accordance with the invention it is provided that, starting from a base value, the electric voltage increases in a time-averaged manner superproportional to the elapsed heating-up time. The invention relates also to a glow plug control unit for carrying out of such a method.

Abstract: A method and device for operation of glow plugs of a Diesel engine in which the type of glow plugs used is determined, by a parameter typical of the glow plugs, for example, the electrical glow plug resistance, being detected and evaluated. The detected values of the parameter typical of the glow plugs are compared with corresponding data for various types of glow plugs stored in the glow controller to determine the type(s) of glow plug(s) in the engine. After identification of the type(s) of glow plug(s), stored sets of parameters, which correspond to the type(s) of glow plug(s) determined, are likewise called upon to control the glow plugs.

Abstract: Method for controlling a group of glow plugs in a diesel engine, which are connected with a direct current source via individual supply lines and which are to be controlled by a pulse width modulation process at the same temperature, at least in time average. The electric resistance of the glow plugs, less the resistance of the supply line to the heating element of the glow plugs, is determined during operation of the engine and a relative pulse width at which the glow plugs are to be operated is calculated from the value so obtained.

Abstract: The invention relates to a method for heating a glow plug to a setpoint temperature using a glow program which specifies the course over time of an effective voltage which is generated using pulse width modulation and is applied to heat the glow plug, wherein the glow program is stored in a control device and is provided for the glow plug and other glow plugs of the same model series, the parameters of which match within the scope of manufacturing tolerances. According to the invention, a deviation of a value of a parameter of the glow plug from a nominal value that is typical for a model series is determined, and the glow program is adapted as a function of the deviation. The invention furthermore relates to a glow plug control device for implementing a method of that type.

Abstract: The invention relates to a method for supplying current to a glow plug in a running diesel engine after reaching the operating temperature thereof by a series of current pulses, wherein a piston of the engine carries out a work cycle comprising several strokes and the glow plug is supplied with current as a function of the strokes of the work cycle such that the electric current supplied in each work cycle is mainly supplied at a predetermined, steady stroke of the piston, wherein control time intervals that follow each other are defined, during which up to two switching processes can be triggered by a control device, by which the glow plug can be connected to a voltage source for creating a current pulse or can be disconnected from the voltage source for ending a current pulse. According to the invention, the control time intervals have a duration that can be varied by the control device as a function of the rotational speed of the engine.

Abstract: The invention relates to a method for operating a glow plug with the engine running, wherein an effective voltage is generated from a vehicle electrical system voltage by pulse width modulation, the effective voltage is applied to the glow plug and changed as a function of engine parameters, a target value of the effective voltage that is dependent on the engine parameters and to which the effective voltage is changed is specified, a maximum increment for a change of the actual value of the effective voltage in at least one direction is specified, and a change of the actual value in at least one direction to a target value that deviates from the actual value by more than the maximum increment is carried out in several steps. The invention further relates to a controller which carries out such a method during operation.

Abstract: The invention describes a method for operating glow plugs in a diesel engine that comprises a housing and a heater element projecting beyond that housing which interacts with an engine control unit and a glow plug control unit which, following a preheating phase, controls the electric power supplied to the glow plugs in dependence on an input received from the engine control unit. According to the invention it is provided that the engine control unit determines a value representative of a temperature that is to be reached at the heater element and the engine control unit transmits that value as target value to the glow plug control unit which converts that target value using an algorithm stored in the glow plug control unit and taking into account the characteristic values stored in the glow plug control unit.

Abstract: A method for determining a heating characteristic of a glow plug, wherein pulse-width-modulated voltage pulses are applied to the glow plug and an electric variable is measured repeatedly during a voltage pulse with the heating characteristic of the glow plug determined by evaluating the difference of successive measurement results of this variable.

Abstract: The invention describes a method for operating glow plugs, that comprise a housing and a heater element projecting beyond that housing, in a diesel engine which interacts with an engine control unit and a glow plug control unit which latter, following a preheating phase, controls the electric power supplied to the glow plugs in response to an input received from the engine control unit. It is provided according to the invention that the engine control unit determines a value representative of a temperature that is to be reached at the heater element and the engine control unit transmits that value as target value to the glow plug control unit which implements that target value using an algorithm stored in the glow plug control unit and with reference to characteristic values stored in the glow plug control unit.

Abstract: Method for controlling a group of glow plugs in a diesel engine, which are connected with a direct current source via individual supply lines and which are to be controlled by a pulse width modulation process at the same temperature, at least in time average. The electric resistance of the glow plugs, less the resistance of the supply line to the heating element of the glow plugs, is determined during operation of the engine and a relative pulse width at which the glow plugs are to be operated is calculated from the value so obtained.