Model predictions are presented to evaluate the electrodynamic parameters as expected at the orbit of the China Seismic-Electromagnetic Satellite (CSES). The main objective of this paper is that of improving the accuracy of the electric field detectors (EFDs), which are installed on CSES and will measure the field vector in a wideband from dc up to 3.5 MHz. The electric field components are derived from the probe floating potential readings, thus an accurate characterization of the space environment is needed to model the currents collected from the ionosphere and establish the EFD probe response. The plasma environment and the magnetic field along the orbit are determined using the standard IRI and IGRF models. Simulations are used to determine the bias currents, which have to be applied to the probes to minimize the contact impedance between the EFDs and the ionospheric plasma. Correction voltages required to remove the $\vec {v}\times \vec {B}$ electric field from the EFD measurements are also estimated.