Download ionic packets, using proxy

in the company where I work we have a proxy server, I configured npm with the company proxy, it works perfect, after that, I configured the proxy session variables for the ionic:
set http_proxy = [proxy server]: [proxy port]
set https_proxy = [proxy server]: [proxy port]

but it is not working yet, when I install an Ex component : $ ionic cordova plugin add cordova-plugin-nativestorage

the console hangs for several minutes, after that, the package is downloaded through npm, is there any other way to configure the proxy in ionic ??
thank you