Dynamic resistance refers to the resistance value of the contact resistance between the brush and the conductive ring that changes with time, operating status and other factors during the operation of the conductive slip ring. Dynamic resistance has the following main effects on the conductive slip ring:
Influence on electrical performance
a. Impact on signal transmission quality: During signal transmission, the presence of dynamic resistance may cause signal attenuation, distortion or interference. For weak signals or high-frequency signals, changes in dynamic resistance may change parameters such as the amplitude and phase of the signal, thereby affecting the accuracy and integrity of the signal. For example, in precision measuring equipment or communication systems, the instability of dynamic resistance may cause increased measurement errors or bit errors in communication signals.
b. Causes heat and energy loss: According to Joule's law, Q=I²RT, changes in dynamic resistance will cause changes in the heat generated by the conductive slip ring during operation. When the dynamic resistance increases, the heat generated under the same current increases, which will not only cause energy waste, but also increase the temperature of the slip ring, thereby affecting its insulation performance and the performance of other components, and in severe cases may even cause damage to the slip ring.
c. Causes voltage drop fluctuations: Changes in dynamic resistance will cause the voltage drop at both ends of the conductive slip ring to fluctuate. In power transmission systems, this may affect the voltage stability at the load end and prevent the equipment from working properly. For example, in some electronic devices with high voltage stability requirements, the voltage drop fluctuation caused by dynamic resistance may cause equipment failure or performance degradation.
Impact on mechanical properties
d. Increased wear: The change in dynamic resistance is usually accompanied by a change in the contact state between the brush and the conductive ring. When the dynamic resistance increases, the contact pressure between the brush and the conductive ring may change, resulting in increased friction, which in turn increases the wear of the brush and the conductive ring. Wear will shorten the service life of the conductive slip ring, increase maintenance costs and equipment downtime.
e.Impact on rotational flexibility: The additional heat and friction generated by the change in dynamic resistance may cause the rotating parts of the slip ring to be subjected to thermal and mechanical stress. Long-term accumulation may cause the rotating parts to deform and jam, affecting the rotational flexibility of the slip ring, and then affecting the operating stability of the entire equipment.
Impact on system stability and reliability
a. Cause system failure: In some complex systems, the instability of the dynamic resistance of the conductive slip ring may trigger a chain reaction, causing the entire system to fail. For example, in the fields of aerospace, industrial automation, etc., the conductive slip ring is a key component. The abnormal change of its dynamic resistance may cause the control system to malfunction or even cause the equipment to lose control.
b. Reduce system reliability: The existence of dynamic resistance increases the uncertainty of the working state of the conductive slip ring, which reduces the reliability of the system. Since the dynamic resistance is affected by many factors, such as ambient temperature, humidity, vibration, etc., its changes are difficult to accurately predict and control, which brings hidden dangers to the long-term stable operation of the system.