A large proportion of the financing was raised by its owner, private equity firm Riverstone Holdings. Pattern, formerly the North American arm of Babcock & Brown, was acquired and rebranded by Riverstone last year.
Pattern Energy said it had invested over $1billion in wind energy projects exceeding a total of $1 billion in the past nine months and has 522.4 MW of North American wind projects in operation or under construction.
Pattern CEO Mike Garland said: "By successfully raising significant equity financing, Pattern Energy is now well capitalized for its growth plans, providing us with the ability to invest in future projects in development, construction and operations, while also giving us the flexibility to accelerate our growth through attractive acquisition opportunities.
"Pattern's strong growth over the past year exceeded our goal of 300-400 megawatts (MW) operating or under construction in our first 18 months."
Last month, Pattern signed a 27-year power purchase agreement with Manitoba Hydro in March for the output of the C$345 million ($344 million), 138MW St Joseph wind farm.
The project, which will utilise 30 Siemens 2.3MW turbines, will be built on farmland about 85 kilometres south of Winnipeg and 20 kilometres north of the US border. It is expected to be online in December.