This paper presents two improved double line voltage synthesis strategies for matrix converters. Both strategies redistribute the on-time intervals of the switches to reduce the output voltage error caused by the limit of minimum safe pulsewidth during commutation process. The first strategy reconstructs the modulation law according to the relationship between the input and the output voltages. The second strategy takes the current relationship into account, and the on-time intervals are calculated using the instantaneous output currents. Without increasing the commutation times and switching losses, the proposed strategies can decrease the number of pulses whose duty cycles are less than the minimum limit and improve the output voltage waveform. Moreover, the second one can also enhance the input current quality. Numerical simulations and experiments with a 10-kW prototype are carried out. The results are given to verify the feasibility and effectiveness of the proposed strategies.