Learn inverter maintenance and read a good book. If you have strong self-study ability, are good at independent thinking and summarizing, and have plenty of time, you can choose to learn inverter maintenance by reading books. You can choose relevant teaching materials or reference books to systematically learn the principle, structure, fault analysis and maintenance methods of frequency converters. The advantage of reading books is that you can freely arrange your study time and schedule, review and consult knowledge points at any time, and save training costs.