Surge voltage generator> is an important tool for evaluating the degree of protection of railway signaling equipment connected to power lines, this article The impact of lightning surge on electronic equipment and the test method, test level and experimental results of the test generator are introduced in detail. In addition, the harm of surge voltage generator> to electronic/electrical equipment has always been a topic of concern to people all over the world. In view of this, many electronic engineers have researched and developed various lightning protection and surge protection equipment to protect electronic/electrical equipment. The commonly used ones are direct current (DC) and alternating current (AC) protection modules, DC protectors are mainly used in signal systems, and AC protectors are used in power systems. Since the electromagnetic environment is extremely complex and prone to instability, in order to protect the equipment against damage caused by overvoltage, it is necessary to install a more scientific and reasonable protection module. The grounding system is also an important part of the overvoltage resistance of the protected device.
1. The response of electronic equipment to lightning surge:
>The voltage and current amplitude generated by lightning surge exceeds twice the normal value, within microseconds occurs; and the charging of the input filter capacitor makes the peak current larger than the steady-state input current. The power supply should limit the shock levels to which switches, rectifiers, fuses, and electromagnetic impedance filters are exposed so that the AC input voltage does not damage the power supply or burn out circuit breakers due to repeated switching. In addition, the impact of the power supply will also cause abnormal operation of electrical equipment such as air conditioners, compressors, elevators, pumps and motors, often requiring replacement of electromechanical components or winding. Failure, restarting or voltage problems of electronic equipment can also affect the service life, as well as damage to diodes, metallization surfaces on component surfaces, damage to printed circuit boards or contact points, damage to triacs/thyristors, and Abnormal situations such as lock-up, loss of control of thyristors or triacs, partial corruption of data files, errors or failures in data processing programs, accelerated aging of components, shortened life of electrical appliances, and decline in output quality of sound and picture quality.
Second, Lightning Surge Immunity Test Method: >
This standard stipulates that the lightning surge test generator should simulate 1.2/50us voltage waveform, 8/20us current waveform, and the combined waveform of voltage waveform 10/700us and current waveform 5/320us, the waveform is coupled to the measured object through the coupling exciter to achieve the test purpose.
In order to effectively install surge voltage generator> protection equipment, we must fully understand the internal performance characteristics of the system and the propagation mode of lightning waves to ensure that reasonable lightning protection measures are taken , Different systems do not require the same lightning protection measures, but the appropriate lightning protection scheme must be determined according to the specific system. In addition to lightning surge protection equipment, the grounding system of the protected device is also very important. Only a complete grounding system can better protect the equipment from damage caused by lightning strikes. When the surge voltage invades electronic equipment, we can effectively protect the equipment from lightning damage by using lightning protection surge protection equipment, forming an effective lightning protection structure.
The signal system is the main foundation of today's electronic information technology, and its development is inseparable from the protection against lightning surges. Surge voltage generator> is the damage to electronic devices and systems caused by force or natural damage. One of the main damages is the failure of the power grid and the household appliances and office equipment powered by it. break down or even burn out. Therefore, effective lightning surge protection measures should be taken to ensure the accuracy and transmission rate of signal transmission.
Third, the test level of the test generator:>
According to the severity of the test voltage, the level of the shock test surge voltage generator> Divided into Level 1, Level 2, Level 3, Level 4 and Level X. Specifically, level X depends on the negotiation between the user and the manufacturer; while other levels depend on the impacted environment (the environment exposed to the possibility of shock) and the installation conditions:
Level 1 refers to close to a safe environment, such as a factory or The control room of a power plant; Level 2 refers to a certain protective environment, such as a factory building without interference; Level 3 refers to a general electromagnetic interference environment without special installation requirements, such as ordinary installed wired networks, industrial workshops and substations; Level 4 Refers to severely disturbing environments, such as civil overhead lines and unprotected high-voltage substations; which level to choose generally depends on product standards.
4. Experimental results:>
The lightning surge test is a destructive test, which can be classified as completely non-destructive and partial failure according to the degree of damage to the test object and complete damage in three cases. For those destructive tests, the tester is responsible for preparing the corresponding spare parts to ensure that the test can be performed reasonably and efficiently. According to the degree of damage to the test object, it can be divided into the following situations:
1. The performance of the test object is normal within the limits specified by the manufacturer, consignor or purchaser.
2. Temporary loss or degradation of function or performance, but recoverable automatically after the disturbance ceases, notOperator intervention is required;
3. Function or performance is temporarily lost or reduced, but requires operator intervention to recover;
4. The hardware or software of the device is damaged or data is lost, resulting in irreversible function or performance loss.