I have already solved my problem.If someone is interested in solution its something like this:
$cart = new Cart($cartId);
$customer = new Customer($cart->id_customer);
$currency = new Currency($cart->id_currency);
$total = (float)$cart->getOrderTotal(true, Cart::BOTH);
$this->module->validateOrder($cart->id, $pspStatusId, $total, $this->module->displayName, NULL, $mailVars, (int)$currency->id, false, $customer->secure_key);