A Conversation with the CTO: Technology, R&D, and Innovation

Q: You have emphasized that Hoymiles is a technology-driven company. How do you ensure that the R&D team is a driving force for the company?

A: The universal requirements for all power electronics products are high efficiency, high conversion efficiency, high reliability, and low cost. We use these simple principles as guidance for our product development, which is in line with the overall market demand. This approach ensures our product competitiveness to a large extent. From a technical perspective, our team consists of experts in power electronics with extensive experience in this field. Our expertise and deep experience in this industry help us develop the most competitive products. As a result, we have always ensured that our products meet the market demand and are competitive.

Q: CEO Yang Bo talked about Hoymiles' shift from focusing on cutting-edge technology to a two-pronged approach to technology development. From an R&D standpoint, how do you plan to implement this change?

A: I understand what Dr. Yang said to be, initially, we were more of a technology-driven company. But now we need to cater the product to the market needs. In the past, we focused on improving our product features while our current focus is not only on delivering top-notch product performance, but also on achieving the highest level of reliability and cost-effectiveness. Additionally, we must improve our product features and user experience. Only then can we satisfy the changing expectations global markets have of this product. In fact, since establishing Hoymiles, we always wanted to deliver the best technology to the world. When taking this "Two-pronged approach", we aim to deliver the best technology to the world.

Q: Regarding these, are there any recent achievements you can share with us?

A: First, I would like to introduce our Wi-Fi integrated microinverter. In the past, our communications solutions utilized private communications protocols. Its reliability and coverage were rather impressive. However, there was a common technical issue in the industry: The lifespan of the communication module for internet connection was short. It is unable to match our 12-year or even longer warranty that covers the lifespan of our microinverters. Thus, we spent some time overcoming this issue. Our current product, the Wi-Fi integrated microinverter, is the result of addressing the market requirements. It comes with the Wi-Fi communications capability and it has a long lifespan and great reliability. This is the first product that we want to introduce today. Second, it is our system optimization. The installation of the microinverter is considered the most flexible and convenient.

However, in reality, we discovered that during applications, the design of the AC trunk cable had various inconveniences, which resulted in a significant impediment and caused wastage. Based on this, Hoymiles R&D engineers used the Lego idea and turned it into detachable modules. The installer or user could combine and match them flexibly and build them as the user wishes. This guarantees reliability and enhances the product’s flexibility. It even makes the assembly interesting and fun. I think this is quite impressive! We look forward to this product hitting the market.

Q: Recently, Hoymiles launched the Wi-Fi integrated microinverter in the Brazilian and Asia Pacific markets. Can you explain why?

A: We considered them first because these two regions particularly need this kind of product, given the application scenarios there. We strive to take the shortest time to launch it to meet our customers’ needs. Following this, we will make this product also available to other markets.

Q: Which technical challenges the R&D team faced deeply impressed you? How were they solved?

A: Encountering difficulties during development is commonplace for the R&D team. In fact, it would be abnormal not to face any obstacles during a period of development. Therefore, R&D personnel generally gets used to encountering problems. This is just a routine state of affairs. In terms of impressive experience, I think back to when the company was still in the early days and had limited resources. As a result, the problems encountered at the time were more pronounced. What impressed me deeply was we lacked adequate testing equipment and personnel during the testing of communication functions,?Our testing engineers relied on their passion to drive the entire team to conduct the testing, and although the process was quite arduous, we were able to obtain the desired performance and results.

As our team continued to grow and we gained access to more resources and equipment, we did not let go of our enthusiasm for technology and pursuit of high-quality products. When we had major projects to do or breakthroughs to make, everyone was able to come together and work with extreme focus, efficiency, and diligence to overcome challenges. As we progress to this day, most of the problems encountered along the way, which has led to the successful launch of our competitive products. I am very grateful to my team.

Q: How do you prioritize the various research topics in the R&D department?

A: We definitely first look at the market demand and the impact of various technologies on different markets or product performances thereon as a short-term reference point. However, we often take a longer-term perspective on this matter. We consider whether the technical accumulation of the entire team or product line is sufficient. We would imagine ourselves standing five to ten years in the future and looking back to see which products or technologies would greatly motivate our future development. That product or technology is what we would assign more weight to. In general, we set priorities based on short-term and long-term considerations.

Q: What role do emerging technologies play in the photovoltaic industry?

A: The progress of technology in each link of the supply chain will push the entire industry to be more mature, reliable, and have lower costs. Taking photovoltaics as an example, the entire project used to rely on subsidies to be able to operate. However, through the efforts of every link in the supply chain, the cost of each link has been reduced without compromising reliability. Only in this way can this technology be widely applied. Without ensuring economic viability, the entire industry cannot mature and develop. In our work on microinverters, we also follow the three simple principles mentioned earlier. High performance and reliability are universal requirements for equipment, and low cost is also a critical factor. If we cannot reduce the cost while ensuring performance and high reliability, the development of the whole industry will be affected.

Q: What are the core advantages of Hoymiles' products?

A: Talking about the core advantages of our products, I would start with the people and the team. After all, our products are developed by engineers working together. Only with engineers who have extensive expertise and experience in power electronics can we ensure that our products are competitive Talent cultivation and recruitment have always been our top priority, and luckily, we've done well in this regard. This has allowed us to develop market-leading products in the microinverter field that continue to lead the market through constant iteration.

The second advantage is our way of thinking. We always take a systemic view of things, rather than just focusing on the product dimension. Consequently, our product development focuses not only on optimizing product performance, but also on optimizing system performance. For example, we decided to develop microinverter systems in the first place that because in distributed PV the microinverter system performs significantly better than the string inverter in that the maintenance is easier, the system efficiency is higher, and particularly it is safer.

In addition, we have utilized our craftsmanship to polish every aspect of the product to the utmost level, achieving high conversion efficiency, high reliability, and low cost, as previously mentioned. Only by considering every aspect can we ensure that our product is competitive.

Q: How does Hoymiles ensure that its products are of optimal quality and performance? What measures has Hoymiles taken in R&D to ensure product reliability and stability?

A: Product reliability and stability generally involve two aspects: R&D and manufacturing. At the R&D level, to ensure product stability, you must have a good system design. Throughout the development process, each step is subject to strict control and review. Experienced and highly-skilled engineers must work together to develop and design a product that is of top-notch quality and performance.

In the manufacturing process, control of each step is also necessary, from raw materials through production process testing to quality laboratory measurements. These are all essential in ensuring product reliability and high performance.

In addition, the designed product must be highly manufacturable and be particularly suitable for mass production, which is also important. The larger-scale production will become increasingly smoother for our products. The quality, reliability, and performance of our products will also be more guaranteed.

Q: What are Hoymiles' innovative ideas for the future?

A: Currently, Hoymiles' main products are PV inverters and energy storage inverters. For PV inverters, we have launched microinverters that can monitor power conversion for each module. That is why they are called module-level power electronics. For alternative solutions, we have released rapid shutdown devices and will release optimizers. RSDs and optimizers, like microinverters, can achieve module-level power electronics transformation and monitoring, making them an ideal choice for distributed applications. RSDs and optimizers go with string inverters, and are suitable for high-power applications, while microinverters are better for low-power applications. By doing this, we have achieved full coverage of the entire power scenario.

Energy storage inverters are a supplement to PV inverters, and they serve to shave peaks and shift load. We have two solutions here. The first is the integration of microinverters and energy storage inverters. Energy storage inverters and photovoltaics will be a very typical platform for household electricity consumption and production. This can also include charging piles and all controllable intelligent appliances, forming a smart home energy system. We will work towards this direction and achieve deep integration at the system level to make the system more intelligent and controllable.

On the other hand, we will also integrate RSDs and optimizers of module-level power electronics with energy storage. Firstly, we will improve our energy storage product line. Energy storage inverters are our latest product series. Currently, we have introduced single-phase and three-phase energy storage systems.

In the future, we will optimize and supplement this product line series, forming a full range of products covering low and high-power classes, single-phase and three-phase options, and working with low-voltage and high-voltage batteries. In this way, we can have a complete product line that has all the advantages of module-level PV and is ready to fit into different settings. We can offer different technical solutions to address the needs of various manufacturers and users.

We will also introduce our second-generation microinverter platform and a new microinverter developed based on this platform. The advancement of microinverter technology mainly relies on two aspects: The first is the progress of power electronics devices, which often helps improve performance significantly. The second is the change in application scenarios, such as those in module power, which can also bring about significant changes to the entire system equipment and products.

Over the past decade, we have mainly developed products based on the first-generation technology platform, resulting in our 1-in-1, 2-in-1, and 4-in-1 product lines. In the next stage, our second-generation platform will mature, and we will introduce a full range of products from 1-in-1 to 4-in-1 based on the second-generation microinverter platform. The first product we will introduce is a 1-in-1 microinverter. It can improve efficiency and reduce system costs, making it more user-friendly. We believe that the launch of our second-generation platform and microinverter will be a great surprise.