Grayson Perry's laugh is a filthy beast of a thing.

It starts at his socks and escalates upwards, before exploding from his mouth and filling the room. A Sid James-worthy laugh, brimming with relish and Rabelaisian raucousness. Like a diesel engine with a dirty mind. It's hard not to laugh along with him.

He's laughing now. A Sid James times three, I reckon. I've just asked him who his ideal audience would be. "Very wealthy oligarchs," he says. "They're my ideal."

Someone should bottle that laugh. Sell it as a cure for depression. And then they could work out how to bottle Perry himself.

Among British artists, Damien Hirst, Tracey Emin and Jack Vettriano may be more famous, but none has done so much for the national joie de vivre as Perry; through his Turner Prize-winning art - all those gorgeous, scatalogical pots, those tapestries that nail modern Britain to the warp and weft - through his openness about his transvestism and of course through his latest role as a TV personality.

Last year Perry's Channel 4 documentary series All In The Best Possible Taste delighted everyone who saw it and now he's back with another, this time about identity. Grayson Perry: Who Are You? features reality TV celebrities, a transgender man, deaf Jews, a white single mother who has converted to Islam, loyalists on the Newtonards Road, a former minister for energy and climate change (who is also a former jailbird), and Alzheimer's sufferers. In each case it ends with Perry making a piece of art about the people in question. A tapestry, pot or embroidery. One of them even gets a silk scarf.

Issues of taste and identity have always been part of what he does. "I'm always interested in what goes on right in front of us," he says. "The subtext of life. Taste is there all the time and in the same way identity is with us all the time. It shapes us and we shape it. It's a word that crops up a lot in politics and the media. And it's always a black lesbian in a wheelchair." There's that laugh again.

It's 5pm on a Monday. The day is winding down. We're sitting in his north London studio not far from where he lives, eating vaguely disturbing cakes that look like cartoon characters. Perry's friend Eric is working in the other room, while Perry, in T-shirt and stubble and sitting on a sofa under a tapestry that features images of himself and his psychotherapist wife Philippa, is slightly tired. He was up till four in the morning. "It was a great party."

We've already talked about the indyref (he commiserates with the losing side but says he's happy it turned out as it did) and celebrity (we'll come back to that), but for now, the TV series is front and centre.

What he really wanted to look at, he says, is people who have had their identity threatened or changed. "The one identity I definitely wanted to talk about was the white middle-class man. They don't even seem to notice that they have an identity. It's so interlaced with society because society has been largely shaped in their image. So we chose Chris Huhne because he was very much in that classic mould. Privately educated, went to Oxford, PPE, 60 years old. He was right bang in the target zone and of course we got him just before he went into the clink."

You do wonder how Perry can get people to unburden themselves in front of the camera. "I'm nice!" he tells me. "They're very receptive. And they've watched the other series so they know they're not going to get stitched up and of course they're getting a portrait in the National Portrait Gallery. That was actually more of a draw than being on telly."

And so he got to go on a UVF march and sit in on a deaf family's conversation, one that goes to the heart of the matter of identity. "We have an amazing shot in the final episode where a mother and daughter are discussing what takes precedence in their lives. Jewishness versus deafness, this horizontal culture of deafness versus this vertical identity of Jewishness which is passed down. It's the perfect cross-hairs of identity happening in a kitchen in north London and it's really moving."

Time to ask then what identities are in the cross-hairs for Perry himself. "Well, working-classness, Essexness. That is certainly a vertical identity. Cross that with the art world, transvestism … Success. Celebrity is a curious tribe. That's why they all hang out together because they've had this weird thing happen to them. I've become more well-known. It's kind of strange. It's fascinating, brilliant. A laugh. A hoot." What's the downside? "There's a few niggly things, but it's a luxury problem. Check your privileges."

The TV series is not art, he points out. "The idea that you drag everything you do and call it art seems old-fashioned to me. I want art to do the job it does perfectly well. It's a unique, beautiful, real object that's there in front of you." He doesn't name names but it's clear there are some artists he feels don't manage that. I don't think he's a big fan of video art for one thing.

He can trace his own artistic impulses back to childhood. "Being working-class is a f***ing advantage. Low-impulse control, which comes with the territory. You get a middle-class person, they've got to de-stress themselves before they can start expressing themselves.

"Then you throw in a bit of trauma - which the human mind has this amazing ability to sugar-coat, usually with some kind of sexual predilection. It finds a way of getting something out of it.

"And then my father was a very skilful engineer. He could make anything. That must have been handed down to me at some point, that agency to be able to change the world, make the world.

"So a combination of that and retreating to the bedroom with a box of Lego or an Airfix kit or a sketchbook. Having an imaginary world. It's all those things. They all feed into the channels I still use to this day. They're well worn motorways of thought."

The trauma in question was itself a combination of his mother having an affair with the milkman, his father disappearing from his life (in his autobiography, he writes: "My dad became a ghost then"; Perry didn't see him between the ages of seven and 15), and a violent stepfather he lived in fear of.

Looking back, does he think his parents failed him? "Failed me?" He sounds slightly incredulous at the question. "They did the best they could. But they were f***ed up themselves. That's what happens. I'm not going to get into a blame game about it. My mother was the ninth of nine - she's still alive - she was pretty bonkers. And my stepfather's father was like a monster. He was violent and when he was in a nursing home he sexually assaulted one of the nurses. So they weren't equipped for whatever reason. But I managed. It worked out."

Perry's daughter Flo was born in 1992. How did he find fatherhood when he had no workable model of it himself? "I had to do it very self-consciously. 'I'm not going to f*** it up.' But you know, it's the old adage. 'Act as if.' If you act as if you're something it very quickly becomes natural. You inhabit the role. So I'd like to think I did the fatherhood thing OK.

"The weird thing about having a child is that … I don't know if this is something that is recognised within psychiatry … But I've heard other people talk about the fact that when their child was at the age when they had difficulties a kind of mirroring happens. That's when things often come home to roost badly. It did for me when my daughter was four years old. That was quite heavy. It might have been a combination of baby jail - young kid, you go mad - and historic stuff for me, bringing all that back. So that's when I ended up in therapy."

He recommends the experience. "Really good. Terrific. That's where I met Eric." He looks into the other room. "Sorry Eric, is that too much information? He's not my therapist, by the way."

Perry was a withdrawn child who spent a lot of time imagining the fantasy world of his teddy bear Alan Measles - still one of the signifers of his art. Yet by the time he was at art college, he was appearing in student shows naked but for a coat of paint. Perry doesn't seem interested in why that might be. But he does say his neo-naturist phase was good training. "It's incredible for confidence. It's probably the least working-class trait, that. Confidence. That's why you pay for private school. That's what they run on - that overdose of confidence. But it's really useful the more successful you are as an artist. I stand up and talk in front of thousands of people or go on telly. You've got to be relaxed. Being relaxed is essential to being creative."

I suppose appearing naked is easy after you've come out as a transvestite. As a kid, Perry borrowed dresses from his sister. He was outed when his stepsister discovered his diary.

Dressing up in women's clothing was always a sexual thing for him, he's said. He's 54 now. Is it still? "Oh yeah. It's historic stuff but curiously I've talked to old trannies who are into their 70s and 80s. There's one old guy who said, 'I haven't had an erection for years but I dress up more than ever,' so it's not purely a sex thing, is it? It's a kind of psychosexual thing. The sexual thing is hardwired at puberty pretty much. It's still there. I still get turned on by the idea …"

There's a question of identity here too, perhaps. Is Claire (his female alter-ego) a different person to Grayson? "No. I think she might have been earlier. But now she's me in a dress. The only thing I probably do differently as Claire is walk. It looks nicer in a frock to walk in a ladylike way, to sit in a ladylike way. Lots of trannies at a trannie do wouldn't even register that. They'd be sitting like this [he mimes sitting with his legs apart], talking about the traffic on the M4."

Every year he works with fashion students at St Martins, getting them to design clothes for Claire. "I've got red carpet evening gowns, a clown suit. I've got a lovely little orange mini number." He shows me a picture of it.

Very Pucci, I say. "Yeah, Pucci. I always feel a bit Faye Dunaway in it. I don't look like Faye Dunaway in The Thomas Crown Affair but I feel like it."

Does Grayson Perry ever dress up? "Yeah. I like bright colours. American Apparel has been a gift to me. You can go in and buy T-shirts and socks in any colours. Hackett is good for colour. I got a fantastic pair of billiard green trousers in there the other day."

Of course when he won the Turner Prize in 2003 Claire accepted the prize and he turned up in a "mother of the bride" outfit to receive his CBE from Prince Charles. "When you win the Turner Prize you get an enormous kick of celebrity, fame, notoriety, which I embraced wholeheartedly."

Does he feel part of the establishment now? "Totally, 100 per cent. I am the establishment. People always think that's supposed to be a bad thing. My counter to that is that all the things that people see as rebellious are often hackneyed, so I think to change the world I need to get myself well ensconced into the establishment and try to do it from there." Does he want to change the world, then? "I'm not a politician but you've got to make a little impact. But I'm not like Eddie Izzard. Christ, no."

Who are his audience? He thinks it's pretty mainstream. He makes pots and ceramics and tapestries after all. "I'm interested in the middle. I look out at my audiences at talks and they're a Radio 4 lot. Students as well. I want broad appeal. You can't be an elitist, difficult Turner Prize artist. You've got to be a bit more accessible. Because a lot of art isn't to do with communication."

Does he think a lot of modern art is a closed system? "Yeah and I'm not interested in that at all. I'm interested in talking to a broad audience."

I ask him who exactly he wants to reach. That's when he makes his crack about wealthy oligarchs. "Because I've got to live. And that's the irony of it. I make 20 works a year. I only need 20 people in the audience financially. But in order for those people to be interested in what I do I need to build up status. For museums the more popular you are the more keen they are to get you because you bring an audience. If you're a popular artist they'll give you a show because they want footfall to justify their public money. So it works for me, that system." All that said, his biggest thrill is if someone with a broad working-class accent tells him they like his work.

Being an artist is something you become over years and it needs the approbation of your peers, he says. "You can shout that you're an artist until the cows come home but if everybody looks at you askance you're not really. There was a point in my late 20s when I was what they call an artist's artist."

He's a bit more than that now. Does he think he's in the pantheon? "Jeff Koons probably thinks he's in the pantheon. Maybe he should be. I wouldn't put myself there. I'm working on it." n

Grayson Perry: Who Are You? begins on Channel 4 on Wedneday at 10pm; the accompanying free display at the National Portrait Gallery, sponsored by Coutts, opens on October 25. His book Playing To The Gallery is published by Penguin, priced £10.49.