<span style="font-family: 'Times New Roman',serif; font-size: 12pt; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;" lang="EN-US">The recent </span><span style="font-family: 'Times New Roman',serif; font-size: 12pt; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-GB; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;" lang="EN-GB">developments</span><span style="font-family: 'Times New Roman',serif; font-size: 12pt; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;" lang="EN-US"> in high power rated Voltage Source Converters (VSCs) and the control strategies have resulted in their successful application in HVDC transmission systems, which have become an attractive option for renewable energy applications or for distribution power in large metropolitan areas. A 153^th order multiple-input multiple-output (MIMO) small-signal model of DC network model based on VSC-HVDC system and controls is developed in state-space form within MATLAB. The optimum values of the controller gains are selected by analyzing the root locus of the analytical model. The developed small-signal detailed models are linearized and implemented in MATLAB. The validity and accuracy of the proposed models are verified against nonlinear PSCAD/ EMTDC and a summary of the model structure and controls is presented in detailed. Confirmation of the effectiveness of optimization gains is done by simulating the modelled system in MATLAB and PSCAD software. There simulation results performed with very good matching is confirmed in the time domain. It is the most detailed model currently available.</span>