Bearing Corrosion Protection: Han Cheng Conductive Rings for Electric Vehicles

Patent issues are one of the fatal problems in this industry. How to judge the effectiveness of bearing grounding protection measures?\nFrom the above-mentioned typical shaft voltage discharge forms, it can be seen that the bearing current mainly manifests as:\n- Resistive discharge current during low speed and high vibration conditions\n- Capacitive breakdown discharge current during unstable oil film conditions and stable conditions (e.g. acceleration and deceleration)\nTherefore, Han Cheng believes that there are three main aspects to consider for the impact on the protective effect:\n1. The ratio of the impedance of the parallel grounding bypass to the impedance of the bearing, especially the high-frequency dynamic impedance.\n2. The magnitude of the decrease in shaft voltage (percentage).\n3. The amplitude of the shaft voltage after the decrease (Vp-p). \nHow to effectively protect bearing corrosion?\nUnder high-frequency conditions, the distribution of the electric field on the shaft is non-uniform.\n- Single beam 100N*30s does not fall off.\n- The fiber and metal are perfectly fitted to improve conductivity, and the loop resistance is 100% \u003c 1\u03a9.\n- It does not contain any organic components, and there is no possibility of incompatibility with materials inside the motor (such as ATF oil).\n- Ensure constant interference fit throughout the entire service life.\n- Ensure that the fiber tip contacts the shaft surface to maximize conductivity.\n- Ensure that the conductivity does not decrease in an oil-cooled environment.\n- Ensure that the fiber does not break under various operating conditions.\nDifferent needs require different solutions. A series of product solutions.\nAdditional information \u2013 Appendix\nCase 1 \u2013 New energy commercial vehicle\n- A certain brand of electric bus had a large area of bearing corrosion problems after-sales, and the customer contacted Han Cheng for help.\n- After installing the conductive ring from Han Cheng, the shaft voltage was effectively reduced, and the bearing corrosion problem was solved.\n- Under 400V, the measured values of a 150KW drive motor are as follows:\n - Impedance below 100m\u03a9\n - EMI interference reduced to normal levels\n - Peak voltage on the shaft decreased from 15.2V to 2V (no insulated bearing installed)\n - After the motor shaft operated for 210,000 km, the shaft voltage was 3.2V (4V for newly installed motors by foreign counterparts)\nCase 2 \u2013 New energy passenger car\n- A certain vehicle manufacturer retrofitted bearing protection measures. Due to the lack of installation space on the motor shaft, we creatively changed the conductive ring into a VGS rod-shaped conductive brush, which brushes the inner wall of the hollow shaft to achieve a significant reduction in shaft voltage.\n- 150KW, 350V voltage, 16,000 rpm water-cooled motor\n- Conductive rod\n- Motor shaft hole\n- After installing the Han Cheng conductive rod\n-\nCase 3 \u2013 New energy SUV\n- 430V, 150KW, 16,000 RPM water-cooled motor\n- Without any measures, the highest tested shaft voltage is only about 6V, and bearing corrosion is severe.\n- After installing VGR-52.73-30-8, the shaft voltage is significantly reduced.\nCase 4 \u2013 New energy passenger car\n- A leading brand of new energy vehicles selected Han Cheng's conductive ring for batch installation in their popular car models after comparing various solutions, providing full protection for motor bearings.\nTesting conditions\n- Shaft voltage Vp-p\n- Without conductive ring\n- With Han Cheng conductive ring\n- Competitor's conductive ring\n- Oil-cooled motor\n2022 Domestic New Energy Vehicle Supply Analysis\nCompany introduction:\n- 10 years of experience in bearing corrosion protection, over 20 years of experience in frequency conversion motor protection\n- Main employees come from Fortune 500 companies\n- Main business: bearing corrosion protection conductive rings, high-performance impregnating resins\n- Planned capacity: 10 million conductive rings per year, 10,000 tons of impregnating resins per year\n- Quality principles: highest quality principle, comprehensive quality principle, quality backlash principle\n- Vision and mission: make frequency conversion motors better serve human life\n- Core values: innovation-driven, safety and reliability, inclusiveness and cooperation, courage and responsibility\n- With the development of automotive motor technology, bearing corrosion issues are increasingly prominent and must be addressed\n- Automotive motor bearing corrosion is mainly caused by frequency conversion drive\n- Among various technical solutions, the conductive fiber drainage solution stands out due to its comprehensiveness and overall advantages\n- Han Cheng's fiber conductive ring can effectively drain shaft current, reduce shaft voltage, and help customers solve bearing corrosion problems. In some cases, it works better when used in combination with insulated bearings or high-conductivity shaft sleeves.