Financial details of the acquisition have not been revealed but La Caisse said Invenergy would remain the controlling shareholder.
The Canadian pension fund manager had previously purchased a stake in a portfolio of Invenergy's projects in the US and Canada.
In 2013, the two companies agreed a deal that saw the Canadian firm buy a minority interest in 13 wind projects for US$500 million.
The portfolio had a total capacity of 1.5GW and included the 138.6MW Le Plateau I project in Québec, east Canada.
In April 2014, Le Caisse also invested C$42 million (US$39.5 million) in Invenergy's 135.7MW Parc des Moulins, also in Québec.
Invenergy said it has developed 54 projects, totalling more than 5GW of capacity in Canada, the US, the UK and Poland.