Wind Power

Advanced Blade Pitch Systems Part 2 — Three Key Insights

In part one of this article, we looked at five trends in the rapidly evolving technology of advanced blade pitch systems. Let’s take a look now at three key insights for making the right blade pitch system decisions.

1. Reliability always comes first

Any company looking to integrate a pitch system into its turbine design must, first and foremost, recognize that the pitch system is a central part of the turbine safety system. It has to work seven days a week, day in, day out. That’s why OEMs should always select partners backed by a strong track record in system reliability.

Of course, cost is an important factor, as well as reducing structural loads and extending the turbine lifetime. Nonetheless, unwavering reliability is the very first consideration to take into account, because a failing pitch system can outright destroy the asset it was meant to protect.

One important element is the speed at which the system can pitch blades according to variations in weather conditions. This is vital when coping with extreme weather events that will eventually hit your fleet during its 25-year lifetime. When exposed to such events, lower quality blade pitch systems may not be able to cut out of the wind fast enough or as calculated, and damage the entire turbine.

The guarantee for reliability comes from the extensive field experience brought by thousands of pitch systems designed for different turbines, operating in different climates, and different countries. Only a handful of companies in the global wind industry have acquired such track records.

2. 360 degree understanding of wind turbine control

Secondly, pitch systems are an integrated part of the overall turbine control system, which means that the continued cohesion of its various components must be ensured. Experience has shown that pitch failures often come from a lack of understanding of how intimately all the turbine control elements interact with one another.

To get the right pitch system for a turbine prototype, a complete set of simulations is required. This can be achieved by using “Bladed Models” with a full WTG model simulation. Combined with practice, know-how and a lot of field experience, thorough simulations can determine the optimal solution.

It will also help to ensure that the turbine is suited to its operating conditions. In this instance, an extensive and diversified track record and the breadth of feedback data it generates, is important.

And yet, to build their turbine, some OEMs quaintly still imagine that they can save costs by shopping around for the cheapest off-the-shelf components. Lowering the turbine CAPEX becomes the only objective worth pursuing for them. Nonetheless, they are likely to learn that, for all the money it might save upfront, they will remain at the mercy of potentially downtime. When failure does occur, the odds are that the unfortunate OEMs will be looking for a recognized control expert within days.

Off-the-shelf products can do what they can do. At the very least, the entire control system must be thoroughly tested and assembly must be optimal. Even then, they are never going to be as well-integrated as when both pitch and turbine control systems come from the same supplier.

The final advantage resulting from having a single technology partner for the combined control and pitch system is effective troubleshooting. It enables you to address all lines of inquiries to a single point of contact. It is especially useful since in most cases, OEM do not know which element of the system is actually causing the failure. Finally, it will help to resolve issues quickly as well as to maintain a well-optimized complete system.

3. The benefits of system flexibility

Successful pitch control suppliers are, above all, technology companies that have demonstrated their ability to stay at the peak of innovation over time. The level of flexibility of the selected technology is a key parameter to take into account.

With regard to turbine development, OEMs must take a long-term view of pitch control, and look for a technology partner that can supply the system they need today, but also the system that will be needed in the future. Indeed, all the lessons learned from the first design can be drawn upon to create the next, more advanced system, instead of starting from scratch with every turbine prototype.

“Successful pitch control suppliers have demonstrated their ability to stay at the peak of innovation.” — Click to Tweet

A flexible system can adapt more easily as the turbine design gets upgraded. Being flexible means staying clear of systems that have a low degree of versatility and adaptability, such as compact low voltage pitch systems, for example. Going with mainstream technology offers high sub-components availability over time, and will ensure you get the best long-term benefits out of your pitch control system.

Behind Every Successful Project, There Is a Successful Partnership

Achieving optimal pitch control and minimizing structural loads requires a unique set of design and technology skills. It requires expertise in load simulation, control algorithms and wind turbine optimization. It demands a partner that can deliver a complete design process and run all simulations of the turbine to truly deliver the optimum pitch system that is needed for prospective field conditions. And above all, it demands a partner that can deliver the twin goals of optimal annual production and asset safety.

Lead image credit: Mita-Teknik