Diesel genset controller as the diesel engine power control equipment, diesel and from their place of work close to the generator. Thus, the working environment is harsh, often in hot, humid, and there are a lot of strong electromagnetic interference environment. Diesel generator set controller as a more sophisticated control devices, require a more reliable design to prevent all interference signal through different pathways into the controller, affecting the normal operation of the controller. Therefore, during the controller design, you want to be taken seriously interfering signals, to take the necessary measures to eliminate or suppress.

First, we must understand the type of interference signals in nature. In addition to the influence of interference signal, the interference to distinguish between primary and secondary signals, the interference of the main signal processing.

There are three kinds of interference signals, namely:

● space interference (magnetic interference).

● Process channel interference.

● power system disturbances.

Spatial interference, also known as external interference, generally refers to the spatial electromagnetic interference.Throughout the controller system, most likely is a strong electromagnetic field radiated electromagnetic interference generator. Since the controller must be installed near the diesel generator, so susceptible to interference from outside signals.

Channel interference generally refers to the process of process control or the entire computer data acquisition and control system analog interference / digital signal input / output channels generated. It includes channel circuits, devices and the use of controlled objects. These objects include sensor devices such as power drive. Moreover, the distribution channel circuit components, as well as the mutual position of the line will be distributed capacitance and other factors affect the work of the computer.

Interference is also known as the power supply system disturbances, mainly from the power supply and power lines.This part of the controller is not affected, because we used to do a battery power supply, and then through a high quality power supply voltage of +5 V conversion module into the controller needs.

In order to prevent the normal operation of the system interference effects in the design of printed circuits, interference has taken the following measures:

● Ground Design: The circuit belongs to the low-frequency circuits, small inductance affect its wiring between the components, and the formation of ground circuit for circulation disturbance greater impact, so a single-point ground, ground bold, reduced ground resistance avoid because of different ground potentials arising from poor ground thickness, resulting in reduced DSP anti-interference ability.

● Power Line Design: Cloth power cord, try bold line width, the power lines and data lines to the same.

● Configure decoupling capacitors: in all parts of the printing plate configuration decoupling capacitor is a conventional printed board design practice, direct access to 0.1pF tiles between each IC power line and ground decoupling capacitors help to improve chip noise immunity.

● printed board device layout: with other logic circuits, when the device is arranged, the relevant frequency devices try to put too close to something, to get a better anti-interference effects, such as crystal and CPU clock inputs are easy to produce Noise should be close to each other.

● UO channel interference measures: Since the electromagnetic actuator control signal, speed sensors , cylinder temperature, oil temperature sensor to the control system, such as a transmission line is longer, generally in the range of 1-2 meters, in order to ensure long-term reliability of the transmission, the transmission line You must use shielded cable, and some misfortune combined use of optical isolation, and low impedance. Optical coupling together isolated pulse can be effectively suppressed, and various noise, so that the SNR of the channel process is greatly improved.

Strong electromagnetic interference in the environment, you can put the entire device into the controller shield inner cover, to prevent interference caused by electromagnetic field of the whole system.

In the software used in the design can be applied to digital filtering, fault-tolerant technology.