© 2018 American Physical Society. The evolution of the low temperature antiferromagnetic conical (characterized by two, commensurate and incommensurate propagation vectors), and the high temperature collinear spin arrangements of the 20% Co-doped MnWO4 multiferroic has been studied in the presence of magnetic field up to 60 T by means of macroscopic magnetic and pyroelectric measurements, and by neutron diffraction experiments in fields up to 12 T on a single crystal. The complete magnetoelectric phase diagrams for magnetic fields along distinct magnetic directions with respect to the spin structure have been constructed up to magnetic field values exceeding those necessary to induce a spin-flip transition into the paramagnetic state. The differences in the topology of the diagrams are discussed. The obtained results might be common for other magnetic materials possessing conical antiferromagnetic structures.