In the operation of modern power plant boilers, the reliability of the ignition system directly affects the unit startup efficiency and safety performance. As the core equipment in the field of industrial boilers, the stable operation of the JGD-20 high-energy igniter depends on the precise timing matching of the fuel injection pressure and the ignition arc. This matching process involves the coordinated optimization of fuel atomization quality, arc energy release timing and system control logic, which is a key technical link to improve the ignition success rate and reduce the failure rate.

1. Working principle and core parameters of the JGD-20 ignition system

The JGD-20 high-energy igniter is an automatic ignition device based on the principle of high-voltage arc discharge. Its core components include high-voltage generator, ignition rod, fuel nozzle and control system. During the ignition process, the high-voltage generator transmits 20 joules of high-frequency electrical energy to the ignition rod through a high-voltage cable to generate a high-energy arc; at the same time, the fuel nozzle sprays the fuel (light oil or heavy oil) into the arc area in an atomized state, and ignites the fuel with the help of the high temperature of the arc to form a stable flame.

The stable operation of the system depends on the coordination of multiple technical parameters:

The fuel injection pressure directly affects the atomization effect of the fuel. Excessive pressure will cause the atomized particles to be too fine, which may reduce the utilization rate of the ignition energy; insufficient pressure will result in insufficient atomization, and the contact area between the fuel and the arc will be reduced, which may easily cause ignition failure.

The timing control of the ignition arc includes the timing and duration of the arc triggering. The propulsion of the JGD-20 ignition rod, the synchronization of arc energy release and fuel injection must be accurately matched to ensure that the fuel is ignited within the optimal window period.

The control system logic realizes the dynamic adjustment of the ignition rod position, fuel valve opening and combustion-supporting air through local manual and remote program control, providing technical support for timing matching.

2. Co-optimization path of fuel injection pressure and ignition arc timing

(I) Adjustment strategy of fuel injection pressure

The reasonable setting of fuel injection pressure is the basis for ensuring the quality of atomization. According to the design specifications of the ignition rod JGD-20, the fuel injection pressure is usually controlled within the range of 0.8-1.2 MPa. In actual adjustment, dynamic calibration should be carried out in combination with the fuel type (light oil or heavy oil) and the boiler combustion chamber structure:

Light fuel has a lower viscosity and requires a lower pressure for atomization, but uneven injection caused by too low pressure should be avoided. At this time, the injection pressure can be stabilized at 0.8-1.0 MPa by adjusting the fuel pump outlet valve or pressure regulating valve.

Heavy fuel has a higher viscosity and requires a higher injection pressure (1.0-1.2 MPa) to ensure sufficient atomization. At the same time, the fuel filter and nozzle need to be cleaned regularly to prevent impurities from clogging and affecting the atomization effect.

In addition, the fuel injection pressure is closely related to the physical position of the ignition rod. If the JGD-20 ignition rod is offset due to long-term high-temperature use, the arc area may be misaligned with the fuel injection trajectory. At this time, the installation angle or position of the ignition rod needs to be adjusted to make the arc center coincide with the fuel atomization cone, thereby improving the ignition success rate.

(II) Accurate control of ignition arc timing

The timing control of the ignition arc involves the coordination of arc triggering timing and duration. The igniter JGD-20 supports three control modes (local manual, remote inching, DCS program control), and its core logic is:

Synchronization of ignition rod advancement and arc triggering: In the local manual mode, the operator needs to trigger the ignition button after the ignition rod JGD-20 is fully in place to ensure that the arc releases energy at the moment when fuel injection begins. The remote program control mode automatically completes this process through a preset program to avoid manual operation delays.

Optimization of arc energy release window: Arc energy release needs to be synchronized with the initial stage of fuel injection. If the arc is triggered too early, the fuel has not yet reached the arc area, which may lead to energy waste; if the trigger is too late, the fuel may deviate from the optimal ignition position due to the injection inertia.

Dynamic adjustment of combustion-supporting air: The combustion-supporting air needs to be turned off at the beginning of ignition to avoid airflow interfering with flame stability. After the fire detection signal confirms that the ignition is successful, the combustion-supporting air is gradually turned on to strengthen combustion. This process needs to be coordinated with the arc duration to ensure that the flame can still be maintained stably after the arc exits.

(III) Coordinated debugging method of pressure and timing

The matching of fuel injection pressure and ignition arc timing needs to be achieved through systematic debugging:

Static calibration stage: Under cold conditions, use a pressure gauge and oscilloscope to monitor the fuel injection pressure and arc waveform, adjust the parameters of the fuel pump and high-voltage generator, and ensure that both are stably output within the preset range.

Dynamic simulation test: Under simulated working conditions, the fuel injection trajectory and arc energy distribution are recorded by sensors, and the spatial overlap and time synchronization of the two are analyzed. For example, if the arc energy release lags behind the fuel injection, it can be corrected by shortening the control loop signal delay or adjusting the ignition rod advancement speed.

Hot state verification and iteration: In the actual ignition process, the flame morphology and ignition success rate are evaluated through the feedback of the fire detection signal and the combustion monitoring data. If ignition delay or flameout occurs, the fuel pressure or timing parameters need to be adjusted retroactively, and the test needs to be repeated until the optimal matching state is achieved.

3. Precautions and maintenance suggestions in practical applications

Continuous guarantee of atomization quality: Regularly clean the fuel pipes and nozzles to prevent impurities from causing poor atomization. For heavy oil systems, it is recommended to add atomization aids to the fuel to reduce viscosity to improve atomization uniformity.

Maintenance of high-voltage cables and JGD-20 ignition rods: The contact ends of high-voltage shielded cables need to be checked regularly to ensure that there is no looseness or oxidation. Although the ignition rod has high temperature resistance (long-term 1300℃), its surface electrode is easily passivated due to high-temperature oxidation and needs to be replaced or polished regularly to maintain discharge efficiency.

Optimization of control system logic: In the DCS program control mode, fuzzy control or PID algorithm can be introduced to dynamically adjust the fuel pressure and ignition timing according to real-time combustion data to further improve system adaptability.

Emergency handling of faults: If the phenomenon of “normal ignition but no ignition” occurs, it is necessary to check the moisture in the oil circuit, the position of the ignition rod and the atomization state of the fuel first to avoid blind repeated ignition and equipment overload.

The stability improvement of the JGD-20 fuel ignition gun is essentially a precise matching process between the fuel injection pressure and the ignition arc timing. By optimizing the fuel pressure parameters, accurately controlling the arc triggering timing, and combining the system debugging and maintenance strategy, the ignition failure rate can be significantly reduced, the equipment life can be extended, and finally the efficient and safe startup and operation of the boiler can be achieved.

When looking for high-quality, reliable ignition guns, YOYIK is undoubtedly a choice worth considering. The company specializes in providing a variety of power equipment including steam turbine accessories, and has won wide acclaim for its high-quality products and services. For more information or inquiries, please contact the customer service below:
E-mail: sales@yoyik.com
Tel: +86-838-2226655
Whatsapp: +86-13618105229

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