let json =

    [
        {
            "TimeStamp": "2018-10-02T11:30:07.211Z",
            "Value": "109316.4691",
            "Quality": 3
        },
        {
            "TimeStamp": "2018-10-02T11:30:49.811Z",
            "Value": "109312.0255",
            "Quality": 3
        },
        {
            "TimeStamp": "2018-10-02T11:31:04.011Z",
            "Value": "109310.5443",
            "Quality": 3
        },
        {
            "TimeStamp": "2018-10-02T11:31:11.111Z",
            "Value": "109309.8037",
            "Quality": 3
        }
    ];


let fields = Object.keys(json[0]);

function replacer(key, value) {
    return value === null ? '' : value;
}

let csv = json.map(row => {
    return fields.map(fieldName => {
        return JSON.stringify(row[fieldName], replacer)
    }).join(',')
});

csv.unshift(fields.join(',')); // add header column

console.log(csv.join('\r\n'));