New series for powers of $\pi$ and related congruences

Via symbolic computation we deduce 97 new type series for powers of $\pi$ related to Ramanujan-type series. Here are three typical examples: $$\sum _{k=0}^{\mathrm{\infty }}\frac{P(k)\left(\genfrac{}{}{0px}{}{2k}{k}\right)\left(\genfrac{}{}{0px}{}{3k}{k}\right)\left(\genfrac{}{}{0px}{}{6k}{3k}\right)}{(k+1)(2k-1)(6k-1)(-640320{)}^{3k}}=\frac{18\times {557403}^3\sqrt{10005}}{5\pi }$$ with \begin{align*}P(k) = &637379600041024803108 k^2 + 657229991696087780968 k \&+ 19850391655004126179, \end{align*} $$\sum _{k=1}^{\mathrm{\infty }}\frac{(3k+1){16}^k}{(2k+1{)}^2{k}^3{\left(\genfrac{}{}{0px}{}{2k}{k}\right)}^3}=\frac{{\pi }^2-8}{2},$$ and $$\sum _{n=0}^{\mathrm{\infty }}\frac{3n+1}{(-100{)}^n}\sum _{k=0}^n{\left(\genfrac{}{}{0px}{}{n}{k}\right)}^2{T}_k(1,25)T_{n-k}(1,25)=\frac{25}{8\pi },$$ where the generalized central trinomial coefficient $T_k(b,c)$ denotes the coefficient of $x^k$ in the expansion of $(x^2+bx+c{)}^k$. We also formulate a general characterization of rational Ramanujan-type series for $1\mathrm{/}\pi$ via congruences, and pose 117 new conjectural series for powers of $\pi$ via looking for corresponding congruences. For example, we conjecture that $$\sum _{k=0}^{\mathrm{\infty }}\frac{39480k+7321}{(-29700{)}^k}{T}_k(14,1)T_k(11,-11{)}^2=\frac{6795\sqrt{5}}{\pi }\mathrm{.}$$ Eighteen of the new series in this paper involve some imaginary quadratic fields with class number $8$.