The plans, "Project Thor" were put forward by the company two years ago in an attempt to build up the scheme.
At the time, BHS was owned by Sir Philip Green's Arcadia group.
The plans were not implemented and BHS went into administration last month, with a Â£571m pension scheme hole.
BHS at that time was owned by the little-known consortium Retail Acquisitions which bought it from Sir Philip for Â£1.
Project Thor was a complicated set of plans, revealed for the first time on Newsnight but planned in 2014.
Among its proposals was giving holders of smaller pensions the chance to have them paid off, as well as changes to contracts with suppliers and an Â£80m injection from Sir Philip Green, comprised of cash and cancelled loans. Its ambition was to push the BHS scheme nearer to being 100% funded.
Newsnight understands the plans were put forward to the Pensions Regulator for approval, but this was never granted. The plans were eventually withdrawn some months before the sale to Retail Acquisitions.
The project was not mentioned when the Regulator's chief executive, Lesley Titcomb, gave evidence to a joint meeting of the Works and Pensions and Business, Innovation and Skills committees.
The chairman of the Work and Pensions Committee, Frank Field, has now written to Ms Titcomb, asking for her analysis of what Project Thor was, how it was structure and why approval was not granted.
She has also been asked to provide more details of meetings between the regulator and Arcadia during the run-up to the sale of BHS.
During her evidence, Ms Titcomb said that she had first read of the company's sale "in the newspaper", leading to an angry response from Sir Philip Green and a clarification from herself.

Denis O'Brien was granted a high court injunction in May to stop RTÉ reporting details of his personal finances.
TD Catherine Murphy later made comments regarding his finances under privilege in the Dáil (parliament).
Media organisations returned to court to seek clarity.
Ms Murphy told the Dáil that Mr O'Brien owed the former Anglo Irish Bank upwards of 500m euro (£362m).
Ms Murphy, an independent left-wing TD, said Mr O'Brien was attempting to pay loans back at an interest rate of just over 1%, when it was arguable that the correct rate should be over 7%.
But those comments went largely unreported in the Republic of Ireland because of the high court injunction restraining RTÉ from reporting on Mr O'Brien's personal finances and his relationship with the former Anglo Irish Bank, now the nationalised Irish Bank Resolution Corporation (IBRC).
On Tuesday, lawyers for several media organisations returned to the high court to hear judge Donald Binchy say that he never intended nor could he order any interference with what a TD may say under privilege in the Dáil.
He could not stop any media organisation from reporting those remarks, he said.
That clarification has been welcomed by the national broadcaster RTÉ and other media organisations, and by the National Union of Journalists.

Officers from the Environment Agency found 20,000 tyres when they visited the site at Seacoast Road, Bellarena, near Limavady, last year.
The men did not have a licence to keep tyres or to use any material as sea defences.
They both pleaded guilty to one charge under waste legislation and one under the marine legislation.
Gregory Allen, 43, of Seacoast Road Bellarena and David McCullough, 68, of Old Antrim Road Ballymena, were sentenced to four months in prison, suspended for two years.
The tyres were found buried in and resting beside the shoreline of Lough Foyle.
A formal notice to remove the waste, sent to Mr Allen, was not complied with.
The site was owned by Mr Allen and rented by Mr McCullough.

9 May 2015 Last updated at 09:34 BST
Gentoo penguins tend to live in ice-free areas near Antarctica, and make special circular nest made out of stones, moss and feathers.
Their steam-lined bodies mean they can swim up to 22 miles and hour underwater, faster than any other diving bird.
Senior penguin keeper at the zoo Dawn Nicoll said: "We are really happy that the first of the gentoo penguin eggs have hatched".
MPs investigating the collapse of BHS have written to the Pensions Regulator, demanding more information about plans to restructure the pension scheme - first revealed on the BBC's Newsnight.
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A high court judge in the Republic of Ireland has ruled that the media can report what was said in the Irish parliament under privilege about the country's richest man.
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Two men discovered using thousands of tyres as an illegal sea defence have been given suspended sentences.
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Egg-cellent news the first gentoo penguins chicks have arrived at Edinburgh zoo this year.