In an electromagnetic interference environment, to enhance the anti-interference ability of a single-phase bistable latching relay, it is necessary to start from shielding, grounding, circuit optimization and other aspects to build a comprehensive protection system. First of all, a reasonable shielding design is the first line of defense against electromagnetic interference. The selection of the shell material of the relay is crucial. The use of metal materials with high magnetic permeability, such as Permalloy and Iron-Ni alloy, can effectively block the intrusion of external magnetic fields. The relay is completely wrapped in a shielding shell to form a closed shielding space, so that the interference magnetic field generates eddy currents in the shielding layer, consumes the magnetic field energy, and thus reduces the impact on the internal components of the relay. At the same time, for the lead part of the relay, a shielded cable is also required to prevent the interference signal from entering the internal circuit of the relay through the lead coupling.
The optimization of grounding measures is a key link in enhancing the anti-interference ability. Good grounding can provide a low-impedance discharge path for interference signals and avoid the accumulation of interference signals inside the relay. In the design of the relay, an independent grounding terminal should be set to ensure that the grounding connection is firm and reliable. Connect the metal shell of the relay to the grounding terminal to keep it at the same potential as the earth, effectively reducing the interference voltage generated by electrostatic induction. At the same time, for the circuit board inside the relay, the grounding line should be reasonably planned, and single-point grounding or multi-point grounding should be adopted to avoid the formation of a grounding loop and prevent the electromagnetic interference generated by the loop current from affecting the normal operation of the relay.
The optimization of circuit design can fundamentally improve the anti-interference performance of the relay. In the driving circuit of the single-phase bistable latching relay, adding a filter circuit is a common method. By setting appropriate filters at the power input and signal input ends, such as low-pass filters, common-mode filters, etc., the entry of high-frequency interference signals can be effectively suppressed. The filter can filter out interference signals higher than the operating frequency of the relay and only allow useful signals to pass, thereby ensuring the stability of the relay drive circuit. In addition, the use of components with good anti-interference performance in the circuit, such as operational amplifiers with high common-mode rejection ratios, low-noise resistors and capacitors, etc., can also enhance the overall anti-interference ability of the circuit.
The application of isolation technology can effectively cut off the propagation path of interference signals. Optical isolation or electromagnetic isolation is used at the input and output ends of the relay to electrically isolate the internal circuit of the relay from the external circuit. Photoelectric isolation uses optical signal transmission to completely isolate electrical connections and effectively prevent external electromagnetic interference from entering the relay through the circuit. Electromagnetic isolation uses transformers and other devices to transmit signals, which can also avoid the intrusion of interference signals. Through isolation technology, even if the external circuit is subject to strong electromagnetic interference, it will not affect the normal operation of the internal circuit of the relay, thereby significantly improving the anti-interference ability of the relay.
The layout and wiring design of the single-phase bistable latching relay also have an important impact on its anti-interference performance. In the design of the internal circuit board of the relay, the layout of components is reasonably planned, and sensitive components and interference source components are arranged separately to reduce the electromagnetic coupling between them. For example, the coil and contact of the relay are arranged separately to avoid the magnetic field generated by the coil from interfering with the contact circuit. At the same time, optimize the wiring method, shorten the length of the signal transmission line, reduce the area of the signal loop, and reduce the influence of electromagnetic induction. Use a reasonable routing direction to avoid parallel routing and cross routing to prevent crosstalk between signals. Through careful layout and wiring design, the electromagnetic interference level inside the relay can be effectively reduced.
Improvements in magnetic circuit design help to improve the anti-interference ability of the relay itself. In the magnetic circuit design of single-phase bistable latching relay, the shape, size and material of the magnetic steel are optimized to improve the stability and anti-interference ability of the magnetic circuit. Selecting magnetic materials with high coercivity and high remanence can enhance the magnetic retention force, so that the relay can still maintain a stable working state when it is affected by external interference magnetic fields. At the same time, the air gap and magnetic resistance distribution of the magnetic circuit are reasonably designed to make the magnetic field distribution of the magnetic circuit more uniform, reduce the magnetic circuit distortion caused by external magnetic field interference, and thus ensure the normal switching and holding function of the relay.
Through strict testing and verification of single-phase bistable latching relay, problems in anti-interference performance can be discovered and solved in time. Under electromagnetic interference environments of different intensities and frequencies, the relay is comprehensively tested for performance, including electrical parameter testing, action reliability testing, etc. Through testing, the working state of the relay under various interference conditions is evaluated, and the degree of influence of interference on the performance of the relay is analyzed. According to the test results, the design and process of the relay are optimized and improved, and the anti-interference measures are continuously improved to ensure that the relay can work stably and reliably in a complex electromagnetic interference environment.
