This paper studies the fuzzy logic controller (FLC) design for multi-variable fuzzy systems based on the semi-tensor product of matrices, and presents several new results. A new expression of fuzzy rules for multi-variable FLC is introduced, which is very convenient to use in fuzzy logic inference. Based on the new expression of fuzzy rules, the complex fuzzy reasoning is converted into simple algebraic equations by constructing structural matrices of the FLC. A simulation example is given to demonstrate the effectiveness of the proposed approach. A set of least in-degree controls that remove possible fabricated variables are constructed, and an algorithm is given to design the least in-degree controls when the control rules are incomplete. Principles are proposed for dealing with the inconsistency of fuzzy control rules. Finally, the results obtained in this paper are applied to the design of fuzzy controller for energy management and control strategy of parallel hybrid electric vehicles (PHEV).